root/drivers/android/binder.c

DEFINITIONS

1. binder_set_stop_on_user_error
2. binder_stats_deleted
3. binder_stats_created
4. binder_transaction_log_add
5. _binder_proc_lock
6. _binder_proc_unlock
7. _binder_inner_proc_lock
8. _binder_inner_proc_unlock
9. _binder_node_lock
10. _binder_node_unlock
11. _binder_node_inner_lock
12. _binder_node_inner_unlock
13. binder_worklist_empty_ilocked
14. binder_worklist_empty
15. binder_enqueue_work_ilocked
16. binder_enqueue_deferred_thread_work_ilocked
17. binder_enqueue_thread_work_ilocked
18. binder_enqueue_thread_work
19. binder_dequeue_work_ilocked
20. binder_dequeue_work
21. binder_dequeue_work_head_ilocked
22. binder_dequeue_work_head
23. binder_has_work_ilocked
24. binder_has_work
25. binder_available_for_proc_work_ilocked
26. binder_wakeup_poll_threads_ilocked
27. binder_select_thread_ilocked
28. binder_wakeup_thread_ilocked
29. binder_wakeup_proc_ilocked
30. binder_set_nice
31. binder_get_node_ilocked
32. binder_get_node
33. binder_init_node_ilocked
34. binder_new_node
35. binder_free_node
36. binder_inc_node_nilocked
37. binder_inc_node
38. binder_dec_node_nilocked
39. binder_dec_node
40. binder_inc_node_tmpref_ilocked
41. binder_inc_node_tmpref
42. binder_dec_node_tmpref
43. binder_put_node
44. binder_get_ref_olocked
45. binder_get_ref_for_node_olocked
46. binder_cleanup_ref_olocked
47. binder_inc_ref_olocked
48. binder_dec_ref_olocked
49. binder_get_node_from_ref
50. binder_free_ref
51. binder_update_ref_for_handle
52. binder_dec_ref_for_handle
53. binder_inc_ref_for_node
54. binder_pop_transaction_ilocked
55. binder_thread_dec_tmpref
56. binder_proc_dec_tmpref
57. binder_get_txn_from
58. binder_get_txn_from_and_acq_inner
59. binder_free_txn_fixups
60. binder_free_transaction
61. binder_send_failed_reply
62. binder_cleanup_transaction
63. binder_get_object
64. binder_validate_ptr
65. binder_validate_fixup
66. binder_do_fd_close
67. binder_deferred_fd_close
68. binder_transaction_buffer_release
69. binder_translate_binder
70. binder_translate_handle
71. binder_translate_fd
72. binder_translate_fd_array
73. binder_fixup_parent
74. binder_proc_transaction
75. binder_get_node_refs_for_txn
76. binder_transaction
77. binder_free_buf
78. binder_thread_write
79. binder_stat_br
80. binder_put_node_cmd
81. binder_wait_for_work
82. binder_apply_fd_fixups
83. binder_thread_read
84. binder_release_work
85. binder_get_thread_ilocked
86. binder_get_thread
87. binder_free_proc
88. binder_free_thread
89. binder_thread_release
90. binder_poll
91. binder_ioctl_write_read
92. binder_ioctl_set_ctx_mgr
93. binder_ioctl_get_node_info_for_ref
94. binder_ioctl_get_node_debug_info
95. binder_ioctl
96. binder_vma_open
97. binder_vma_close
98. binder_vm_fault
99. binder_mmap
100. binder_open
101. binder_flush
102. binder_deferred_flush
103. binder_release
104. binder_node_release
105. binder_deferred_release
106. binder_deferred_func
107. binder_defer_work
108. print_binder_transaction_ilocked
109. print_binder_work_ilocked
110. print_binder_thread_ilocked
111. print_binder_node_nilocked
112. print_binder_ref_olocked
113. print_binder_proc
114. print_binder_stats
115. print_binder_proc_stats
116. binder_state_show
117. binder_stats_show
118. binder_transactions_show
119. proc_show
120. print_binder_transaction_log_entry
121. binder_transaction_log_show
122. init_binder_device
123. binder_init

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* binder.c
   3  *
   4  * Android IPC Subsystem
   5  *
   6  * Copyright (C) 2007-2008 Google, Inc.
   7  */
   8 
   9 /*
  10  * Locking overview
  11  *
  12  * There are 3 main spinlocks which must be acquired in the
  13  * order shown:
  14  *
  15  * 1) proc->outer_lock : protects binder_ref
  16  *    binder_proc_lock() and binder_proc_unlock() are
  17  *    used to acq/rel.
  18  * 2) node->lock : protects most fields of binder_node.
  19  *    binder_node_lock() and binder_node_unlock() are
  20  *    used to acq/rel
  21  * 3) proc->inner_lock : protects the thread and node lists
  22  *    (proc->threads, proc->waiting_threads, proc->nodes)
  23  *    and all todo lists associated with the binder_proc
  24  *    (proc->todo, thread->todo, proc->delivered_death and
  25  *    node->async_todo), as well as thread->transaction_stack
  26  *    binder_inner_proc_lock() and binder_inner_proc_unlock()
  27  *    are used to acq/rel
  28  *
  29  * Any lock under procA must never be nested under any lock at the same
  30  * level or below on procB.
  31  *
  32  * Functions that require a lock held on entry indicate which lock
  33  * in the suffix of the function name:
  34  *
  35  * foo_olocked() : requires node->outer_lock
  36  * foo_nlocked() : requires node->lock
  37  * foo_ilocked() : requires proc->inner_lock
  38  * foo_oilocked(): requires proc->outer_lock and proc->inner_lock
  39  * foo_nilocked(): requires node->lock and proc->inner_lock
  40  * ...
  41  */
  42 
  43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  44 
  45 #include <linux/fdtable.h>
  46 #include <linux/file.h>
  47 #include <linux/freezer.h>
  48 #include <linux/fs.h>
  49 #include <linux/list.h>
  50 #include <linux/miscdevice.h>
  51 #include <linux/module.h>
  52 #include <linux/mutex.h>
  53 #include <linux/nsproxy.h>
  54 #include <linux/poll.h>
  55 #include <linux/debugfs.h>
  56 #include <linux/rbtree.h>
  57 #include <linux/sched/signal.h>
  58 #include <linux/sched/mm.h>
  59 #include <linux/seq_file.h>
  60 #include <linux/string.h>
  61 #include <linux/uaccess.h>
  62 #include <linux/pid_namespace.h>
  63 #include <linux/security.h>
  64 #include <linux/spinlock.h>
  65 #include <linux/ratelimit.h>
  66 #include <linux/syscalls.h>
  67 #include <linux/task_work.h>
  68 
  69 #include <uapi/linux/android/binder.h>
  70 #include <uapi/linux/android/binderfs.h>
  71 
  72 #include <asm/cacheflush.h>
  73 
  74 #include "binder_alloc.h"
  75 #include "binder_internal.h"
  76 #include "binder_trace.h"
  77 
  78 static HLIST_HEAD(binder_deferred_list);
  79 static DEFINE_MUTEX(binder_deferred_lock);
  80 
  81 static HLIST_HEAD(binder_devices);
  82 static HLIST_HEAD(binder_procs);
  83 static DEFINE_MUTEX(binder_procs_lock);
  84 
  85 static HLIST_HEAD(binder_dead_nodes);
  86 static DEFINE_SPINLOCK(binder_dead_nodes_lock);
  87 
  88 static struct dentry *binder_debugfs_dir_entry_root;
  89 static struct dentry *binder_debugfs_dir_entry_proc;
  90 static atomic_t binder_last_id;
  91 
  92 static int proc_show(struct seq_file *m, void *unused);
  93 DEFINE_SHOW_ATTRIBUTE(proc);
  94 
  95 /* This is only defined in include/asm-arm/sizes.h */
  96 #ifndef SZ_1K
  97 #define SZ_1K                               0x400
  98 #endif
  99 
 100 #define FORBIDDEN_MMAP_FLAGS                (VM_WRITE)
 101 
 102 enum {
 103         BINDER_DEBUG_USER_ERROR             = 1U << 0,
 104         BINDER_DEBUG_FAILED_TRANSACTION     = 1U << 1,
 105         BINDER_DEBUG_DEAD_TRANSACTION       = 1U << 2,
 106         BINDER_DEBUG_OPEN_CLOSE             = 1U << 3,
 107         BINDER_DEBUG_DEAD_BINDER            = 1U << 4,
 108         BINDER_DEBUG_DEATH_NOTIFICATION     = 1U << 5,
 109         BINDER_DEBUG_READ_WRITE             = 1U << 6,
 110         BINDER_DEBUG_USER_REFS              = 1U << 7,
 111         BINDER_DEBUG_THREADS                = 1U << 8,
 112         BINDER_DEBUG_TRANSACTION            = 1U << 9,
 113         BINDER_DEBUG_TRANSACTION_COMPLETE   = 1U << 10,
 114         BINDER_DEBUG_FREE_BUFFER            = 1U << 11,
 115         BINDER_DEBUG_INTERNAL_REFS          = 1U << 12,
 116         BINDER_DEBUG_PRIORITY_CAP           = 1U << 13,
 117         BINDER_DEBUG_SPINLOCKS              = 1U << 14,
 118 };
 119 static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR |
 120         BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION;
 121 module_param_named(debug_mask, binder_debug_mask, uint, 0644);
 122 
 123 char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES;
 124 module_param_named(devices, binder_devices_param, charp, 0444);
 125 
 126 static DECLARE_WAIT_QUEUE_HEAD(binder_user_error_wait);
 127 static int binder_stop_on_user_error;
 128 
 129 static int binder_set_stop_on_user_error(const char *val,
 130                                          const struct kernel_param *kp)
 131 {
 132         int ret;
 133 
 134         ret = param_set_int(val, kp);
 135         if (binder_stop_on_user_error < 2)
 136                 wake_up(&binder_user_error_wait);
 137         return ret;
 138 }
 139 module_param_call(stop_on_user_error, binder_set_stop_on_user_error,
 140         param_get_int, &binder_stop_on_user_error, 0644);
 141 
 142 #define binder_debug(mask, x...) \
 143         do { \
 144                 if (binder_debug_mask & mask) \
 145                         pr_info_ratelimited(x); \
 146         } while (0)
 147 
 148 #define binder_user_error(x...) \
 149         do { \
 150                 if (binder_debug_mask & BINDER_DEBUG_USER_ERROR) \
 151                         pr_info_ratelimited(x); \
 152                 if (binder_stop_on_user_error) \
 153                         binder_stop_on_user_error = 2; \
 154         } while (0)
 155 
 156 #define to_flat_binder_object(hdr) \
 157         container_of(hdr, struct flat_binder_object, hdr)
 158 
 159 #define to_binder_fd_object(hdr) container_of(hdr, struct binder_fd_object, hdr)
 160 
 161 #define to_binder_buffer_object(hdr) \
 162         container_of(hdr, struct binder_buffer_object, hdr)
 163 
 164 #define to_binder_fd_array_object(hdr) \
 165         container_of(hdr, struct binder_fd_array_object, hdr)
 166 
 167 enum binder_stat_types {
 168         BINDER_STAT_PROC,
 169         BINDER_STAT_THREAD,
 170         BINDER_STAT_NODE,
 171         BINDER_STAT_REF,
 172         BINDER_STAT_DEATH,
 173         BINDER_STAT_TRANSACTION,
 174         BINDER_STAT_TRANSACTION_COMPLETE,
 175         BINDER_STAT_COUNT
 176 };
 177 
 178 struct binder_stats {
 179         atomic_t br[_IOC_NR(BR_FAILED_REPLY) + 1];
 180         atomic_t bc[_IOC_NR(BC_REPLY_SG) + 1];
 181         atomic_t obj_created[BINDER_STAT_COUNT];
 182         atomic_t obj_deleted[BINDER_STAT_COUNT];
 183 };
 184 
 185 static struct binder_stats binder_stats;
 186 
 187 static inline void binder_stats_deleted(enum binder_stat_types type)
 188 {
 189         atomic_inc(&binder_stats.obj_deleted[type]);
 190 }
 191 
 192 static inline void binder_stats_created(enum binder_stat_types type)
 193 {
 194         atomic_inc(&binder_stats.obj_created[type]);
 195 }
 196 
 197 struct binder_transaction_log binder_transaction_log;
 198 struct binder_transaction_log binder_transaction_log_failed;
 199 
 200 static struct binder_transaction_log_entry *binder_transaction_log_add(
 201         struct binder_transaction_log *log)
 202 {
 203         struct binder_transaction_log_entry *e;
 204         unsigned int cur = atomic_inc_return(&log->cur);
 205 
 206         if (cur >= ARRAY_SIZE(log->entry))
 207                 log->full = true;
 208         e = &log->entry[cur % ARRAY_SIZE(log->entry)];
 209         WRITE_ONCE(e->debug_id_done, 0);
 210         /*
 211          * write-barrier to synchronize access to e->debug_id_done.
 212          * We make sure the initialized 0 value is seen before
 213          * memset() other fields are zeroed by memset.
 214          */
 215         smp_wmb();
 216         memset(e, 0, sizeof(*e));
 217         return e;
 218 }
 219 
 220 /**
 221  * struct binder_work - work enqueued on a worklist
 222  * @entry:             node enqueued on list
 223  * @type:              type of work to be performed
 224  *
 225  * There are separate work lists for proc, thread, and node (async).
 226  */
 227 struct binder_work {
 228         struct list_head entry;
 229 
 230         enum {
 231                 BINDER_WORK_TRANSACTION = 1,
 232                 BINDER_WORK_TRANSACTION_COMPLETE,
 233                 BINDER_WORK_RETURN_ERROR,
 234                 BINDER_WORK_NODE,
 235                 BINDER_WORK_DEAD_BINDER,
 236                 BINDER_WORK_DEAD_BINDER_AND_CLEAR,
 237                 BINDER_WORK_CLEAR_DEATH_NOTIFICATION,
 238         } type;
 239 };
 240 
 241 struct binder_error {
 242         struct binder_work work;
 243         uint32_t cmd;
 244 };
 245 
 246 /**
 247  * struct binder_node - binder node bookkeeping
 248  * @debug_id:             unique ID for debugging
 249  *                        (invariant after initialized)
 250  * @lock:                 lock for node fields
 251  * @work:                 worklist element for node work
 252  *                        (protected by @proc->inner_lock)
 253  * @rb_node:              element for proc->nodes tree
 254  *                        (protected by @proc->inner_lock)
 255  * @dead_node:            element for binder_dead_nodes list
 256  *                        (protected by binder_dead_nodes_lock)
 257  * @proc:                 binder_proc that owns this node
 258  *                        (invariant after initialized)
 259  * @refs:                 list of references on this node
 260  *                        (protected by @lock)
 261  * @internal_strong_refs: used to take strong references when
 262  *                        initiating a transaction
 263  *                        (protected by @proc->inner_lock if @proc
 264  *                        and by @lock)
 265  * @local_weak_refs:      weak user refs from local process
 266  *                        (protected by @proc->inner_lock if @proc
 267  *                        and by @lock)
 268  * @local_strong_refs:    strong user refs from local process
 269  *                        (protected by @proc->inner_lock if @proc
 270  *                        and by @lock)
 271  * @tmp_refs:             temporary kernel refs
 272  *                        (protected by @proc->inner_lock while @proc
 273  *                        is valid, and by binder_dead_nodes_lock
 274  *                        if @proc is NULL. During inc/dec and node release
 275  *                        it is also protected by @lock to provide safety
 276  *                        as the node dies and @proc becomes NULL)
 277  * @ptr:                  userspace pointer for node
 278  *                        (invariant, no lock needed)
 279  * @cookie:               userspace cookie for node
 280  *                        (invariant, no lock needed)
 281  * @has_strong_ref:       userspace notified of strong ref
 282  *                        (protected by @proc->inner_lock if @proc
 283  *                        and by @lock)
 284  * @pending_strong_ref:   userspace has acked notification of strong ref
 285  *                        (protected by @proc->inner_lock if @proc
 286  *                        and by @lock)
 287  * @has_weak_ref:         userspace notified of weak ref
 288  *                        (protected by @proc->inner_lock if @proc
 289  *                        and by @lock)
 290  * @pending_weak_ref:     userspace has acked notification of weak ref
 291  *                        (protected by @proc->inner_lock if @proc
 292  *                        and by @lock)
 293  * @has_async_transaction: async transaction to node in progress
 294  *                        (protected by @lock)
 295  * @accept_fds:           file descriptor operations supported for node
 296  *                        (invariant after initialized)
 297  * @min_priority:         minimum scheduling priority
 298  *                        (invariant after initialized)
 299  * @txn_security_ctx:     require sender's security context
 300  *                        (invariant after initialized)
 301  * @async_todo:           list of async work items
 302  *                        (protected by @proc->inner_lock)
 303  *
 304  * Bookkeeping structure for binder nodes.
 305  */
 306 struct binder_node {
 307         int debug_id;
 308         spinlock_t lock;
 309         struct binder_work work;
 310         union {
 311                 struct rb_node rb_node;
 312                 struct hlist_node dead_node;
 313         };
 314         struct binder_proc *proc;
 315         struct hlist_head refs;
 316         int internal_strong_refs;
 317         int local_weak_refs;
 318         int local_strong_refs;
 319         int tmp_refs;
 320         binder_uintptr_t ptr;
 321         binder_uintptr_t cookie;
 322         struct {
 323                 /*
 324                  * bitfield elements protected by
 325                  * proc inner_lock
 326                  */
 327                 u8 has_strong_ref:1;
 328                 u8 pending_strong_ref:1;
 329                 u8 has_weak_ref:1;
 330                 u8 pending_weak_ref:1;
 331         };
 332         struct {
 333                 /*
 334                  * invariant after initialization
 335                  */
 336                 u8 accept_fds:1;
 337                 u8 txn_security_ctx:1;
 338                 u8 min_priority;
 339         };
 340         bool has_async_transaction;
 341         struct list_head async_todo;
 342 };
 343 
 344 struct binder_ref_death {
 345         /**
 346          * @work: worklist element for death notifications
 347          *        (protected by inner_lock of the proc that
 348          *        this ref belongs to)
 349          */
 350         struct binder_work work;
 351         binder_uintptr_t cookie;
 352 };
 353 
 354 /**
 355  * struct binder_ref_data - binder_ref counts and id
 356  * @debug_id:        unique ID for the ref
 357  * @desc:            unique userspace handle for ref
 358  * @strong:          strong ref count (debugging only if not locked)
 359  * @weak:            weak ref count (debugging only if not locked)
 360  *
 361  * Structure to hold ref count and ref id information. Since
 362  * the actual ref can only be accessed with a lock, this structure
 363  * is used to return information about the ref to callers of
 364  * ref inc/dec functions.
 365  */
 366 struct binder_ref_data {
 367         int debug_id;
 368         uint32_t desc;
 369         int strong;
 370         int weak;
 371 };
 372 
 373 /**
 374  * struct binder_ref - struct to track references on nodes
 375  * @data:        binder_ref_data containing id, handle, and current refcounts
 376  * @rb_node_desc: node for lookup by @data.desc in proc's rb_tree
 377  * @rb_node_node: node for lookup by @node in proc's rb_tree
 378  * @node_entry:  list entry for node->refs list in target node
 379  *               (protected by @node->lock)
 380  * @proc:        binder_proc containing ref
 381  * @node:        binder_node of target node. When cleaning up a
 382  *               ref for deletion in binder_cleanup_ref, a non-NULL
 383  *               @node indicates the node must be freed
 384  * @death:       pointer to death notification (ref_death) if requested
 385  *               (protected by @node->lock)
 386  *
 387  * Structure to track references from procA to target node (on procB). This
 388  * structure is unsafe to access without holding @proc->outer_lock.
 389  */
 390 struct binder_ref {
 391         /* Lookups needed: */
 392         /*   node + proc => ref (transaction) */
 393         /*   desc + proc => ref (transaction, inc/dec ref) */
 394         /*   node => refs + procs (proc exit) */
 395         struct binder_ref_data data;
 396         struct rb_node rb_node_desc;
 397         struct rb_node rb_node_node;
 398         struct hlist_node node_entry;
 399         struct binder_proc *proc;
 400         struct binder_node *node;
 401         struct binder_ref_death *death;
 402 };
 403 
 404 enum binder_deferred_state {
 405         BINDER_DEFERRED_FLUSH        = 0x01,
 406         BINDER_DEFERRED_RELEASE      = 0x02,
 407 };
 408 
 409 /**
 410  * struct binder_proc - binder process bookkeeping
 411  * @proc_node:            element for binder_procs list
 412  * @threads:              rbtree of binder_threads in this proc
 413  *                        (protected by @inner_lock)
 414  * @nodes:                rbtree of binder nodes associated with
 415  *                        this proc ordered by node->ptr
 416  *                        (protected by @inner_lock)
 417  * @refs_by_desc:         rbtree of refs ordered by ref->desc
 418  *                        (protected by @outer_lock)
 419  * @refs_by_node:         rbtree of refs ordered by ref->node
 420  *                        (protected by @outer_lock)
 421  * @waiting_threads:      threads currently waiting for proc work
 422  *                        (protected by @inner_lock)
 423  * @pid                   PID of group_leader of process
 424  *                        (invariant after initialized)
 425  * @tsk                   task_struct for group_leader of process
 426  *                        (invariant after initialized)
 427  * @deferred_work_node:   element for binder_deferred_list
 428  *                        (protected by binder_deferred_lock)
 429  * @deferred_work:        bitmap of deferred work to perform
 430  *                        (protected by binder_deferred_lock)
 431  * @is_dead:              process is dead and awaiting free
 432  *                        when outstanding transactions are cleaned up
 433  *                        (protected by @inner_lock)
 434  * @todo:                 list of work for this process
 435  *                        (protected by @inner_lock)
 436  * @stats:                per-process binder statistics
 437  *                        (atomics, no lock needed)
 438  * @delivered_death:      list of delivered death notification
 439  *                        (protected by @inner_lock)
 440  * @max_threads:          cap on number of binder threads
 441  *                        (protected by @inner_lock)
 442  * @requested_threads:    number of binder threads requested but not
 443  *                        yet started. In current implementation, can
 444  *                        only be 0 or 1.
 445  *                        (protected by @inner_lock)
 446  * @requested_threads_started: number binder threads started
 447  *                        (protected by @inner_lock)
 448  * @tmp_ref:              temporary reference to indicate proc is in use
 449  *                        (protected by @inner_lock)
 450  * @default_priority:     default scheduler priority
 451  *                        (invariant after initialized)
 452  * @debugfs_entry:        debugfs node
 453  * @alloc:                binder allocator bookkeeping
 454  * @context:              binder_context for this proc
 455  *                        (invariant after initialized)
 456  * @inner_lock:           can nest under outer_lock and/or node lock
 457  * @outer_lock:           no nesting under innor or node lock
 458  *                        Lock order: 1) outer, 2) node, 3) inner
 459  * @binderfs_entry:       process-specific binderfs log file
 460  *
 461  * Bookkeeping structure for binder processes
 462  */
 463 struct binder_proc {
 464         struct hlist_node proc_node;
 465         struct rb_root threads;
 466         struct rb_root nodes;
 467         struct rb_root refs_by_desc;
 468         struct rb_root refs_by_node;
 469         struct list_head waiting_threads;
 470         int pid;
 471         struct task_struct *tsk;
 472         struct hlist_node deferred_work_node;
 473         int deferred_work;
 474         bool is_dead;
 475 
 476         struct list_head todo;
 477         struct binder_stats stats;
 478         struct list_head delivered_death;
 479         int max_threads;
 480         int requested_threads;
 481         int requested_threads_started;
 482         int tmp_ref;
 483         long default_priority;
 484         struct dentry *debugfs_entry;
 485         struct binder_alloc alloc;
 486         struct binder_context *context;
 487         spinlock_t inner_lock;
 488         spinlock_t outer_lock;
 489         struct dentry *binderfs_entry;
 490 };
 491 
 492 enum {
 493         BINDER_LOOPER_STATE_REGISTERED  = 0x01,
 494         BINDER_LOOPER_STATE_ENTERED     = 0x02,
 495         BINDER_LOOPER_STATE_EXITED      = 0x04,
 496         BINDER_LOOPER_STATE_INVALID     = 0x08,
 497         BINDER_LOOPER_STATE_WAITING     = 0x10,
 498         BINDER_LOOPER_STATE_POLL        = 0x20,
 499 };
 500 
 501 /**
 502  * struct binder_thread - binder thread bookkeeping
 503  * @proc:                 binder process for this thread
 504  *                        (invariant after initialization)
 505  * @rb_node:              element for proc->threads rbtree
 506  *                        (protected by @proc->inner_lock)
 507  * @waiting_thread_node:  element for @proc->waiting_threads list
 508  *                        (protected by @proc->inner_lock)
 509  * @pid:                  PID for this thread
 510  *                        (invariant after initialization)
 511  * @looper:               bitmap of looping state
 512  *                        (only accessed by this thread)
 513  * @looper_needs_return:  looping thread needs to exit driver
 514  *                        (no lock needed)
 515  * @transaction_stack:    stack of in-progress transactions for this thread
 516  *                        (protected by @proc->inner_lock)
 517  * @todo:                 list of work to do for this thread
 518  *                        (protected by @proc->inner_lock)
 519  * @process_todo:         whether work in @todo should be processed
 520  *                        (protected by @proc->inner_lock)
 521  * @return_error:         transaction errors reported by this thread
 522  *                        (only accessed by this thread)
 523  * @reply_error:          transaction errors reported by target thread
 524  *                        (protected by @proc->inner_lock)
 525  * @wait:                 wait queue for thread work
 526  * @stats:                per-thread statistics
 527  *                        (atomics, no lock needed)
 528  * @tmp_ref:              temporary reference to indicate thread is in use
 529  *                        (atomic since @proc->inner_lock cannot
 530  *                        always be acquired)
 531  * @is_dead:              thread is dead and awaiting free
 532  *                        when outstanding transactions are cleaned up
 533  *                        (protected by @proc->inner_lock)
 534  *
 535  * Bookkeeping structure for binder threads.
 536  */
 537 struct binder_thread {
 538         struct binder_proc *proc;
 539         struct rb_node rb_node;
 540         struct list_head waiting_thread_node;
 541         int pid;
 542         int looper;              /* only modified by this thread */
 543         bool looper_need_return; /* can be written by other thread */
 544         struct binder_transaction *transaction_stack;
 545         struct list_head todo;
 546         bool process_todo;
 547         struct binder_error return_error;
 548         struct binder_error reply_error;
 549         wait_queue_head_t wait;
 550         struct binder_stats stats;
 551         atomic_t tmp_ref;
 552         bool is_dead;
 553 };
 554 
 555 /**
 556  * struct binder_txn_fd_fixup - transaction fd fixup list element
 557  * @fixup_entry:          list entry
 558  * @file:                 struct file to be associated with new fd
 559  * @offset:               offset in buffer data to this fixup
 560  *
 561  * List element for fd fixups in a transaction. Since file
 562  * descriptors need to be allocated in the context of the
 563  * target process, we pass each fd to be processed in this
 564  * struct.
 565  */
 566 struct binder_txn_fd_fixup {
 567         struct list_head fixup_entry;
 568         struct file *file;
 569         size_t offset;
 570 };
 571 
 572 struct binder_transaction {
 573         int debug_id;
 574         struct binder_work work;
 575         struct binder_thread *from;
 576         struct binder_transaction *from_parent;
 577         struct binder_proc *to_proc;
 578         struct binder_thread *to_thread;
 579         struct binder_transaction *to_parent;
 580         unsigned need_reply:1;
 581         /* unsigned is_dead:1; */       /* not used at the moment */
 582 
 583         struct binder_buffer *buffer;
 584         unsigned int    code;
 585         unsigned int    flags;
 586         long    priority;
 587         long    saved_priority;
 588         kuid_t  sender_euid;
 589         struct list_head fd_fixups;
 590         binder_uintptr_t security_ctx;
 591         /**
 592          * @lock:  protects @from, @to_proc, and @to_thread
 593          *
 594          * @from, @to_proc, and @to_thread can be set to NULL
 595          * during thread teardown
 596          */
 597         spinlock_t lock;
 598 };
 599 
 600 /**
 601  * struct binder_object - union of flat binder object types
 602  * @hdr:   generic object header
 603  * @fbo:   binder object (nodes and refs)
 604  * @fdo:   file descriptor object
 605  * @bbo:   binder buffer pointer
 606  * @fdao:  file descriptor array
 607  *
 608  * Used for type-independent object copies
 609  */
 610 struct binder_object {
 611         union {
 612                 struct binder_object_header hdr;
 613                 struct flat_binder_object fbo;
 614                 struct binder_fd_object fdo;
 615                 struct binder_buffer_object bbo;
 616                 struct binder_fd_array_object fdao;
 617         };
 618 };
 619 
 620 /**
 621  * binder_proc_lock() - Acquire outer lock for given binder_proc
 622  * @proc:         struct binder_proc to acquire
 623  *
 624  * Acquires proc->outer_lock. Used to protect binder_ref
 625  * structures associated with the given proc.
 626  */
 627 #define binder_proc_lock(proc) _binder_proc_lock(proc, __LINE__)
 628 static void
 629 _binder_proc_lock(struct binder_proc *proc, int line)
 630         __acquires(&proc->outer_lock)
 631 {
 632         binder_debug(BINDER_DEBUG_SPINLOCKS,
 633                      "%s: line=%d\n", __func__, line);
 634         spin_lock(&proc->outer_lock);
 635 }
 636 
 637 /**
 638  * binder_proc_unlock() - Release spinlock for given binder_proc
 639  * @proc:         struct binder_proc to acquire
 640  *
 641  * Release lock acquired via binder_proc_lock()
 642  */
 643 #define binder_proc_unlock(_proc) _binder_proc_unlock(_proc, __LINE__)
 644 static void
 645 _binder_proc_unlock(struct binder_proc *proc, int line)
 646         __releases(&proc->outer_lock)
 647 {
 648         binder_debug(BINDER_DEBUG_SPINLOCKS,
 649                      "%s: line=%d\n", __func__, line);
 650         spin_unlock(&proc->outer_lock);
 651 }
 652 
 653 /**
 654  * binder_inner_proc_lock() - Acquire inner lock for given binder_proc
 655  * @proc:         struct binder_proc to acquire
 656  *
 657  * Acquires proc->inner_lock. Used to protect todo lists
 658  */
 659 #define binder_inner_proc_lock(proc) _binder_inner_proc_lock(proc, __LINE__)
 660 static void
 661 _binder_inner_proc_lock(struct binder_proc *proc, int line)
 662         __acquires(&proc->inner_lock)
 663 {
 664         binder_debug(BINDER_DEBUG_SPINLOCKS,
 665                      "%s: line=%d\n", __func__, line);
 666         spin_lock(&proc->inner_lock);
 667 }
 668 
 669 /**
 670  * binder_inner_proc_unlock() - Release inner lock for given binder_proc
 671  * @proc:         struct binder_proc to acquire
 672  *
 673  * Release lock acquired via binder_inner_proc_lock()
 674  */
 675 #define binder_inner_proc_unlock(proc) _binder_inner_proc_unlock(proc, __LINE__)
 676 static void
 677 _binder_inner_proc_unlock(struct binder_proc *proc, int line)
 678         __releases(&proc->inner_lock)
 679 {
 680         binder_debug(BINDER_DEBUG_SPINLOCKS,
 681                      "%s: line=%d\n", __func__, line);
 682         spin_unlock(&proc->inner_lock);
 683 }
 684 
 685 /**
 686  * binder_node_lock() - Acquire spinlock for given binder_node
 687  * @node:         struct binder_node to acquire
 688  *
 689  * Acquires node->lock. Used to protect binder_node fields
 690  */
 691 #define binder_node_lock(node) _binder_node_lock(node, __LINE__)
 692 static void
 693 _binder_node_lock(struct binder_node *node, int line)
 694         __acquires(&node->lock)
 695 {
 696         binder_debug(BINDER_DEBUG_SPINLOCKS,
 697                      "%s: line=%d\n", __func__, line);
 698         spin_lock(&node->lock);
 699 }
 700 
 701 /**
 702  * binder_node_unlock() - Release spinlock for given binder_proc
 703  * @node:         struct binder_node to acquire
 704  *
 705  * Release lock acquired via binder_node_lock()
 706  */
 707 #define binder_node_unlock(node) _binder_node_unlock(node, __LINE__)
 708 static void
 709 _binder_node_unlock(struct binder_node *node, int line)
 710         __releases(&node->lock)
 711 {
 712         binder_debug(BINDER_DEBUG_SPINLOCKS,
 713                      "%s: line=%d\n", __func__, line);
 714         spin_unlock(&node->lock);
 715 }
 716 
 717 /**
 718  * binder_node_inner_lock() - Acquire node and inner locks
 719  * @node:         struct binder_node to acquire
 720  *
 721  * Acquires node->lock. If node->proc also acquires
 722  * proc->inner_lock. Used to protect binder_node fields
 723  */
 724 #define binder_node_inner_lock(node) _binder_node_inner_lock(node, __LINE__)
 725 static void
 726 _binder_node_inner_lock(struct binder_node *node, int line)
 727         __acquires(&node->lock) __acquires(&node->proc->inner_lock)
 728 {
 729         binder_debug(BINDER_DEBUG_SPINLOCKS,
 730                      "%s: line=%d\n", __func__, line);
 731         spin_lock(&node->lock);
 732         if (node->proc)
 733                 binder_inner_proc_lock(node->proc);
 734         else
 735                 /* annotation for sparse */
 736                 __acquire(&node->proc->inner_lock);
 737 }
 738 
 739 /**
 740  * binder_node_unlock() - Release node and inner locks
 741  * @node:         struct binder_node to acquire
 742  *
 743  * Release lock acquired via binder_node_lock()
 744  */
 745 #define binder_node_inner_unlock(node) _binder_node_inner_unlock(node, __LINE__)
 746 static void
 747 _binder_node_inner_unlock(struct binder_node *node, int line)
 748         __releases(&node->lock) __releases(&node->proc->inner_lock)
 749 {
 750         struct binder_proc *proc = node->proc;
 751 
 752         binder_debug(BINDER_DEBUG_SPINLOCKS,
 753                      "%s: line=%d\n", __func__, line);
 754         if (proc)
 755                 binder_inner_proc_unlock(proc);
 756         else
 757                 /* annotation for sparse */
 758                 __release(&node->proc->inner_lock);
 759         spin_unlock(&node->lock);
 760 }
 761 
 762 static bool binder_worklist_empty_ilocked(struct list_head *list)
 763 {
 764         return list_empty(list);
 765 }
 766 
 767 /**
 768  * binder_worklist_empty() - Check if no items on the work list
 769  * @proc:       binder_proc associated with list
 770  * @list:       list to check
 771  *
 772  * Return: true if there are no items on list, else false
 773  */
 774 static bool binder_worklist_empty(struct binder_proc *proc,
 775                                   struct list_head *list)
 776 {
 777         bool ret;
 778 
 779         binder_inner_proc_lock(proc);
 780         ret = binder_worklist_empty_ilocked(list);
 781         binder_inner_proc_unlock(proc);
 782         return ret;
 783 }
 784 
 785 /**
 786  * binder_enqueue_work_ilocked() - Add an item to the work list
 787  * @work:         struct binder_work to add to list
 788  * @target_list:  list to add work to
 789  *
 790  * Adds the work to the specified list. Asserts that work
 791  * is not already on a list.
 792  *
 793  * Requires the proc->inner_lock to be held.
 794  */
 795 static void
 796 binder_enqueue_work_ilocked(struct binder_work *work,
 797                            struct list_head *target_list)
 798 {
 799         BUG_ON(target_list == NULL);
 800         BUG_ON(work->entry.next && !list_empty(&work->entry));
 801         list_add_tail(&work->entry, target_list);
 802 }
 803 
 804 /**
 805  * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work
 806  * @thread:       thread to queue work to
 807  * @work:         struct binder_work to add to list
 808  *
 809  * Adds the work to the todo list of the thread. Doesn't set the process_todo
 810  * flag, which means that (if it wasn't already set) the thread will go to
 811  * sleep without handling this work when it calls read.
 812  *
 813  * Requires the proc->inner_lock to be held.
 814  */
 815 static void
 816 binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread,
 817                                             struct binder_work *work)
 818 {
 819         WARN_ON(!list_empty(&thread->waiting_thread_node));
 820         binder_enqueue_work_ilocked(work, &thread->todo);
 821 }
 822 
 823 /**
 824  * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list
 825  * @thread:       thread to queue work to
 826  * @work:         struct binder_work to add to list
 827  *
 828  * Adds the work to the todo list of the thread, and enables processing
 829  * of the todo queue.
 830  *
 831  * Requires the proc->inner_lock to be held.
 832  */
 833 static void
 834 binder_enqueue_thread_work_ilocked(struct binder_thread *thread,
 835                                    struct binder_work *work)
 836 {
 837         WARN_ON(!list_empty(&thread->waiting_thread_node));
 838         binder_enqueue_work_ilocked(work, &thread->todo);
 839         thread->process_todo = true;
 840 }
 841 
 842 /**
 843  * binder_enqueue_thread_work() - Add an item to the thread work list
 844  * @thread:       thread to queue work to
 845  * @work:         struct binder_work to add to list
 846  *
 847  * Adds the work to the todo list of the thread, and enables processing
 848  * of the todo queue.
 849  */
 850 static void
 851 binder_enqueue_thread_work(struct binder_thread *thread,
 852                            struct binder_work *work)
 853 {
 854         binder_inner_proc_lock(thread->proc);
 855         binder_enqueue_thread_work_ilocked(thread, work);
 856         binder_inner_proc_unlock(thread->proc);
 857 }
 858 
 859 static void
 860 binder_dequeue_work_ilocked(struct binder_work *work)
 861 {
 862         list_del_init(&work->entry);
 863 }
 864 
 865 /**
 866  * binder_dequeue_work() - Removes an item from the work list
 867  * @proc:         binder_proc associated with list
 868  * @work:         struct binder_work to remove from list
 869  *
 870  * Removes the specified work item from whatever list it is on.
 871  * Can safely be called if work is not on any list.
 872  */
 873 static void
 874 binder_dequeue_work(struct binder_proc *proc, struct binder_work *work)
 875 {
 876         binder_inner_proc_lock(proc);
 877         binder_dequeue_work_ilocked(work);
 878         binder_inner_proc_unlock(proc);
 879 }
 880 
 881 static struct binder_work *binder_dequeue_work_head_ilocked(
 882                                         struct list_head *list)
 883 {
 884         struct binder_work *w;
 885 
 886         w = list_first_entry_or_null(list, struct binder_work, entry);
 887         if (w)
 888                 list_del_init(&w->entry);
 889         return w;
 890 }
 891 
 892 /**
 893  * binder_dequeue_work_head() - Dequeues the item at head of list
 894  * @proc:         binder_proc associated with list
 895  * @list:         list to dequeue head
 896  *
 897  * Removes the head of the list if there are items on the list
 898  *
 899  * Return: pointer dequeued binder_work, NULL if list was empty
 900  */
 901 static struct binder_work *binder_dequeue_work_head(
 902                                         struct binder_proc *proc,
 903                                         struct list_head *list)
 904 {
 905         struct binder_work *w;
 906 
 907         binder_inner_proc_lock(proc);
 908         w = binder_dequeue_work_head_ilocked(list);
 909         binder_inner_proc_unlock(proc);
 910         return w;
 911 }
 912 
 913 static void
 914 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer);
 915 static void binder_free_thread(struct binder_thread *thread);
 916 static void binder_free_proc(struct binder_proc *proc);
 917 static void binder_inc_node_tmpref_ilocked(struct binder_node *node);
 918 
 919 static bool binder_has_work_ilocked(struct binder_thread *thread,
 920                                     bool do_proc_work)
 921 {
 922         return thread->process_todo ||
 923                 thread->looper_need_return ||
 924                 (do_proc_work &&
 925                  !binder_worklist_empty_ilocked(&thread->proc->todo));
 926 }
 927 
 928 static bool binder_has_work(struct binder_thread *thread, bool do_proc_work)
 929 {
 930         bool has_work;
 931 
 932         binder_inner_proc_lock(thread->proc);
 933         has_work = binder_has_work_ilocked(thread, do_proc_work);
 934         binder_inner_proc_unlock(thread->proc);
 935 
 936         return has_work;
 937 }
 938 
 939 static bool binder_available_for_proc_work_ilocked(struct binder_thread *thread)
 940 {
 941         return !thread->transaction_stack &&
 942                 binder_worklist_empty_ilocked(&thread->todo) &&
 943                 (thread->looper & (BINDER_LOOPER_STATE_ENTERED |
 944                                    BINDER_LOOPER_STATE_REGISTERED));
 945 }
 946 
 947 static void binder_wakeup_poll_threads_ilocked(struct binder_proc *proc,
 948                                                bool sync)
 949 {
 950         struct rb_node *n;
 951         struct binder_thread *thread;
 952 
 953         for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
 954                 thread = rb_entry(n, struct binder_thread, rb_node);
 955                 if (thread->looper & BINDER_LOOPER_STATE_POLL &&
 956                     binder_available_for_proc_work_ilocked(thread)) {
 957                         if (sync)
 958                                 wake_up_interruptible_sync(&thread->wait);
 959                         else
 960                                 wake_up_interruptible(&thread->wait);
 961                 }
 962         }
 963 }
 964 
 965 /**
 966  * binder_select_thread_ilocked() - selects a thread for doing proc work.
 967  * @proc:       process to select a thread from
 968  *
 969  * Note that calling this function moves the thread off the waiting_threads
 970  * list, so it can only be woken up by the caller of this function, or a
 971  * signal. Therefore, callers *should* always wake up the thread this function
 972  * returns.
 973  *
 974  * Return:      If there's a thread currently waiting for process work,
 975  *              returns that thread. Otherwise returns NULL.
 976  */
 977 static struct binder_thread *
 978 binder_select_thread_ilocked(struct binder_proc *proc)
 979 {
 980         struct binder_thread *thread;
 981 
 982         assert_spin_locked(&proc->inner_lock);
 983         thread = list_first_entry_or_null(&proc->waiting_threads,
 984                                           struct binder_thread,
 985                                           waiting_thread_node);
 986 
 987         if (thread)
 988                 list_del_init(&thread->waiting_thread_node);
 989 
 990         return thread;
 991 }
 992 
 993 /**
 994  * binder_wakeup_thread_ilocked() - wakes up a thread for doing proc work.
 995  * @proc:       process to wake up a thread in
 996  * @thread:     specific thread to wake-up (may be NULL)
 997  * @sync:       whether to do a synchronous wake-up
 998  *
 999  * This function wakes up a thread in the @proc process.
1000  * The caller may provide a specific thread to wake-up in
1001  * the @thread parameter. If @thread is NULL, this function
1002  * will wake up threads that have called poll().
1003  *
1004  * Note that for this function to work as expected, callers
1005  * should first call binder_select_thread() to find a thread
1006  * to handle the work (if they don't have a thread already),
1007  * and pass the result into the @thread parameter.
1008  */
1009 static void binder_wakeup_thread_ilocked(struct binder_proc *proc,
1010                                          struct binder_thread *thread,
1011                                          bool sync)
1012 {
1013         assert_spin_locked(&proc->inner_lock);
1014 
1015         if (thread) {
1016                 if (sync)
1017                         wake_up_interruptible_sync(&thread->wait);
1018                 else
1019                         wake_up_interruptible(&thread->wait);
1020                 return;
1021         }
1022 
1023         /* Didn't find a thread waiting for proc work; this can happen
1024          * in two scenarios:
1025          * 1. All threads are busy handling transactions
1026          *    In that case, one of those threads should call back into
1027          *    the kernel driver soon and pick up this work.
1028          * 2. Threads are using the (e)poll interface, in which case
1029          *    they may be blocked on the waitqueue without having been
1030          *    added to waiting_threads. For this case, we just iterate
1031          *    over all threads not handling transaction work, and
1032          *    wake them all up. We wake all because we don't know whether
1033          *    a thread that called into (e)poll is handling non-binder
1034          *    work currently.
1035          */
1036         binder_wakeup_poll_threads_ilocked(proc, sync);
1037 }
1038 
1039 static void binder_wakeup_proc_ilocked(struct binder_proc *proc)
1040 {
1041         struct binder_thread *thread = binder_select_thread_ilocked(proc);
1042 
1043         binder_wakeup_thread_ilocked(proc, thread, /* sync = */false);
1044 }
1045 
1046 static void binder_set_nice(long nice)
1047 {
1048         long min_nice;
1049 
1050         if (can_nice(current, nice)) {
1051                 set_user_nice(current, nice);
1052                 return;
1053         }
1054         min_nice = rlimit_to_nice(rlimit(RLIMIT_NICE));
1055         binder_debug(BINDER_DEBUG_PRIORITY_CAP,
1056                      "%d: nice value %ld not allowed use %ld instead\n",
1057                       current->pid, nice, min_nice);
1058         set_user_nice(current, min_nice);
1059         if (min_nice <= MAX_NICE)
1060                 return;
1061         binder_user_error("%d RLIMIT_NICE not set\n", current->pid);
1062 }
1063 
1064 static struct binder_node *binder_get_node_ilocked(struct binder_proc *proc,
1065                                                    binder_uintptr_t ptr)
1066 {
1067         struct rb_node *n = proc->nodes.rb_node;
1068         struct binder_node *node;
1069 
1070         assert_spin_locked(&proc->inner_lock);
1071 
1072         while (n) {
1073                 node = rb_entry(n, struct binder_node, rb_node);
1074 
1075                 if (ptr < node->ptr)
1076                         n = n->rb_left;
1077                 else if (ptr > node->ptr)
1078                         n = n->rb_right;
1079                 else {
1080                         /*
1081                          * take an implicit weak reference
1082                          * to ensure node stays alive until
1083                          * call to binder_put_node()
1084                          */
1085                         binder_inc_node_tmpref_ilocked(node);
1086                         return node;
1087                 }
1088         }
1089         return NULL;
1090 }
1091 
1092 static struct binder_node *binder_get_node(struct binder_proc *proc,
1093                                            binder_uintptr_t ptr)
1094 {
1095         struct binder_node *node;
1096 
1097         binder_inner_proc_lock(proc);
1098         node = binder_get_node_ilocked(proc, ptr);
1099         binder_inner_proc_unlock(proc);
1100         return node;
1101 }
1102 
1103 static struct binder_node *binder_init_node_ilocked(
1104                                                 struct binder_proc *proc,
1105                                                 struct binder_node *new_node,
1106                                                 struct flat_binder_object *fp)
1107 {
1108         struct rb_node **p = &proc->nodes.rb_node;
1109         struct rb_node *parent = NULL;
1110         struct binder_node *node;
1111         binder_uintptr_t ptr = fp ? fp->binder : 0;
1112         binder_uintptr_t cookie = fp ? fp->cookie : 0;
1113         __u32 flags = fp ? fp->flags : 0;
1114 
1115         assert_spin_locked(&proc->inner_lock);
1116 
1117         while (*p) {
1118 
1119                 parent = *p;
1120                 node = rb_entry(parent, struct binder_node, rb_node);
1121 
1122                 if (ptr < node->ptr)
1123                         p = &(*p)->rb_left;
1124                 else if (ptr > node->ptr)
1125                         p = &(*p)->rb_right;
1126                 else {
1127                         /*
1128                          * A matching node is already in
1129                          * the rb tree. Abandon the init
1130                          * and return it.
1131                          */
1132                         binder_inc_node_tmpref_ilocked(node);
1133                         return node;
1134                 }
1135         }
1136         node = new_node;
1137         binder_stats_created(BINDER_STAT_NODE);
1138         node->tmp_refs++;
1139         rb_link_node(&node->rb_node, parent, p);
1140         rb_insert_color(&node->rb_node, &proc->nodes);
1141         node->debug_id = atomic_inc_return(&binder_last_id);
1142         node->proc = proc;
1143         node->ptr = ptr;
1144         node->cookie = cookie;
1145         node->work.type = BINDER_WORK_NODE;
1146         node->min_priority = flags & FLAT_BINDER_FLAG_PRIORITY_MASK;
1147         node->accept_fds = !!(flags & FLAT_BINDER_FLAG_ACCEPTS_FDS);
1148         node->txn_security_ctx = !!(flags & FLAT_BINDER_FLAG_TXN_SECURITY_CTX);
1149         spin_lock_init(&node->lock);
1150         INIT_LIST_HEAD(&node->work.entry);
1151         INIT_LIST_HEAD(&node->async_todo);
1152         binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1153                      "%d:%d node %d u%016llx c%016llx created\n",
1154                      proc->pid, current->pid, node->debug_id,
1155                      (u64)node->ptr, (u64)node->cookie);
1156 
1157         return node;
1158 }
1159 
1160 static struct binder_node *binder_new_node(struct binder_proc *proc,
1161                                            struct flat_binder_object *fp)
1162 {
1163         struct binder_node *node;
1164         struct binder_node *new_node = kzalloc(sizeof(*node), GFP_KERNEL);
1165 
1166         if (!new_node)
1167                 return NULL;
1168         binder_inner_proc_lock(proc);
1169         node = binder_init_node_ilocked(proc, new_node, fp);
1170         binder_inner_proc_unlock(proc);
1171         if (node != new_node)
1172                 /*
1173                  * The node was already added by another thread
1174                  */
1175                 kfree(new_node);
1176 
1177         return node;
1178 }
1179 
1180 static void binder_free_node(struct binder_node *node)
1181 {
1182         kfree(node);
1183         binder_stats_deleted(BINDER_STAT_NODE);
1184 }
1185 
1186 static int binder_inc_node_nilocked(struct binder_node *node, int strong,
1187                                     int internal,
1188                                     struct list_head *target_list)
1189 {
1190         struct binder_proc *proc = node->proc;
1191 
1192         assert_spin_locked(&node->lock);
1193         if (proc)
1194                 assert_spin_locked(&proc->inner_lock);
1195         if (strong) {
1196                 if (internal) {
1197                         if (target_list == NULL &&
1198                             node->internal_strong_refs == 0 &&
1199                             !(node->proc &&
1200                               node == node->proc->context->binder_context_mgr_node &&
1201                               node->has_strong_ref)) {
1202                                 pr_err("invalid inc strong node for %d\n",
1203                                         node->debug_id);
1204                                 return -EINVAL;
1205                         }
1206                         node->internal_strong_refs++;
1207                 } else
1208                         node->local_strong_refs++;
1209                 if (!node->has_strong_ref && target_list) {
1210                         struct binder_thread *thread = container_of(target_list,
1211                                                     struct binder_thread, todo);
1212                         binder_dequeue_work_ilocked(&node->work);
1213                         BUG_ON(&thread->todo != target_list);
1214                         binder_enqueue_deferred_thread_work_ilocked(thread,
1215                                                                    &node->work);
1216                 }
1217         } else {
1218                 if (!internal)
1219                         node->local_weak_refs++;
1220                 if (!node->has_weak_ref && list_empty(&node->work.entry)) {
1221                         if (target_list == NULL) {
1222                                 pr_err("invalid inc weak node for %d\n",
1223                                         node->debug_id);
1224                                 return -EINVAL;
1225                         }
1226                         /*
1227                          * See comment above
1228                          */
1229                         binder_enqueue_work_ilocked(&node->work, target_list);
1230                 }
1231         }
1232         return 0;
1233 }
1234 
1235 static int binder_inc_node(struct binder_node *node, int strong, int internal,
1236                            struct list_head *target_list)
1237 {
1238         int ret;
1239 
1240         binder_node_inner_lock(node);
1241         ret = binder_inc_node_nilocked(node, strong, internal, target_list);
1242         binder_node_inner_unlock(node);
1243 
1244         return ret;
1245 }
1246 
1247 static bool binder_dec_node_nilocked(struct binder_node *node,
1248                                      int strong, int internal)
1249 {
1250         struct binder_proc *proc = node->proc;
1251 
1252         assert_spin_locked(&node->lock);
1253         if (proc)
1254                 assert_spin_locked(&proc->inner_lock);
1255         if (strong) {
1256                 if (internal)
1257                         node->internal_strong_refs--;
1258                 else
1259                         node->local_strong_refs--;
1260                 if (node->local_strong_refs || node->internal_strong_refs)
1261                         return false;
1262         } else {
1263                 if (!internal)
1264                         node->local_weak_refs--;
1265                 if (node->local_weak_refs || node->tmp_refs ||
1266                                 !hlist_empty(&node->refs))
1267                         return false;
1268         }
1269 
1270         if (proc && (node->has_strong_ref || node->has_weak_ref)) {
1271                 if (list_empty(&node->work.entry)) {
1272                         binder_enqueue_work_ilocked(&node->work, &proc->todo);
1273                         binder_wakeup_proc_ilocked(proc);
1274                 }
1275         } else {
1276                 if (hlist_empty(&node->refs) && !node->local_strong_refs &&
1277                     !node->local_weak_refs && !node->tmp_refs) {
1278                         if (proc) {
1279                                 binder_dequeue_work_ilocked(&node->work);
1280                                 rb_erase(&node->rb_node, &proc->nodes);
1281                                 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1282                                              "refless node %d deleted\n",
1283                                              node->debug_id);
1284                         } else {
1285                                 BUG_ON(!list_empty(&node->work.entry));
1286                                 spin_lock(&binder_dead_nodes_lock);
1287                                 /*
1288                                  * tmp_refs could have changed so
1289                                  * check it again
1290                                  */
1291                                 if (node->tmp_refs) {
1292                                         spin_unlock(&binder_dead_nodes_lock);
1293                                         return false;
1294                                 }
1295                                 hlist_del(&node->dead_node);
1296                                 spin_unlock(&binder_dead_nodes_lock);
1297                                 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1298                                              "dead node %d deleted\n",
1299                                              node->debug_id);
1300                         }
1301                         return true;
1302                 }
1303         }
1304         return false;
1305 }
1306 
1307 static void binder_dec_node(struct binder_node *node, int strong, int internal)
1308 {
1309         bool free_node;
1310 
1311         binder_node_inner_lock(node);
1312         free_node = binder_dec_node_nilocked(node, strong, internal);
1313         binder_node_inner_unlock(node);
1314         if (free_node)
1315                 binder_free_node(node);
1316 }
1317 
1318 static void binder_inc_node_tmpref_ilocked(struct binder_node *node)
1319 {
1320         /*
1321          * No call to binder_inc_node() is needed since we
1322          * don't need to inform userspace of any changes to
1323          * tmp_refs
1324          */
1325         node->tmp_refs++;
1326 }
1327 
1328 /**
1329  * binder_inc_node_tmpref() - take a temporary reference on node
1330  * @node:       node to reference
1331  *
1332  * Take reference on node to prevent the node from being freed
1333  * while referenced only by a local variable. The inner lock is
1334  * needed to serialize with the node work on the queue (which
1335  * isn't needed after the node is dead). If the node is dead
1336  * (node->proc is NULL), use binder_dead_nodes_lock to protect
1337  * node->tmp_refs against dead-node-only cases where the node
1338  * lock cannot be acquired (eg traversing the dead node list to
1339  * print nodes)
1340  */
1341 static void binder_inc_node_tmpref(struct binder_node *node)
1342 {
1343         binder_node_lock(node);
1344         if (node->proc)
1345                 binder_inner_proc_lock(node->proc);
1346         else
1347                 spin_lock(&binder_dead_nodes_lock);
1348         binder_inc_node_tmpref_ilocked(node);
1349         if (node->proc)
1350                 binder_inner_proc_unlock(node->proc);
1351         else
1352                 spin_unlock(&binder_dead_nodes_lock);
1353         binder_node_unlock(node);
1354 }
1355 
1356 /**
1357  * binder_dec_node_tmpref() - remove a temporary reference on node
1358  * @node:       node to reference
1359  *
1360  * Release temporary reference on node taken via binder_inc_node_tmpref()
1361  */
1362 static void binder_dec_node_tmpref(struct binder_node *node)
1363 {
1364         bool free_node;
1365 
1366         binder_node_inner_lock(node);
1367         if (!node->proc)
1368                 spin_lock(&binder_dead_nodes_lock);
1369         else
1370                 __acquire(&binder_dead_nodes_lock);
1371         node->tmp_refs--;
1372         BUG_ON(node->tmp_refs < 0);
1373         if (!node->proc)
1374                 spin_unlock(&binder_dead_nodes_lock);
1375         else
1376                 __release(&binder_dead_nodes_lock);
1377         /*
1378          * Call binder_dec_node() to check if all refcounts are 0
1379          * and cleanup is needed. Calling with strong=0 and internal=1
1380          * causes no actual reference to be released in binder_dec_node().
1381          * If that changes, a change is needed here too.
1382          */
1383         free_node = binder_dec_node_nilocked(node, 0, 1);
1384         binder_node_inner_unlock(node);
1385         if (free_node)
1386                 binder_free_node(node);
1387 }
1388 
1389 static void binder_put_node(struct binder_node *node)
1390 {
1391         binder_dec_node_tmpref(node);
1392 }
1393 
1394 static struct binder_ref *binder_get_ref_olocked(struct binder_proc *proc,
1395                                                  u32 desc, bool need_strong_ref)
1396 {
1397         struct rb_node *n = proc->refs_by_desc.rb_node;
1398         struct binder_ref *ref;
1399 
1400         while (n) {
1401                 ref = rb_entry(n, struct binder_ref, rb_node_desc);
1402 
1403                 if (desc < ref->data.desc) {
1404                         n = n->rb_left;
1405                 } else if (desc > ref->data.desc) {
1406                         n = n->rb_right;
1407                 } else if (need_strong_ref && !ref->data.strong) {
1408                         binder_user_error("tried to use weak ref as strong ref\n");
1409                         return NULL;
1410                 } else {
1411                         return ref;
1412                 }
1413         }
1414         return NULL;
1415 }
1416 
1417 /**
1418  * binder_get_ref_for_node_olocked() - get the ref associated with given node
1419  * @proc:       binder_proc that owns the ref
1420  * @node:       binder_node of target
1421  * @new_ref:    newly allocated binder_ref to be initialized or %NULL
1422  *
1423  * Look up the ref for the given node and return it if it exists
1424  *
1425  * If it doesn't exist and the caller provides a newly allocated
1426  * ref, initialize the fields of the newly allocated ref and insert
1427  * into the given proc rb_trees and node refs list.
1428  *
1429  * Return:      the ref for node. It is possible that another thread
1430  *              allocated/initialized the ref first in which case the
1431  *              returned ref would be different than the passed-in
1432  *              new_ref. new_ref must be kfree'd by the caller in
1433  *              this case.
1434  */
1435 static struct binder_ref *binder_get_ref_for_node_olocked(
1436                                         struct binder_proc *proc,
1437                                         struct binder_node *node,
1438                                         struct binder_ref *new_ref)
1439 {
1440         struct binder_context *context = proc->context;
1441         struct rb_node **p = &proc->refs_by_node.rb_node;
1442         struct rb_node *parent = NULL;
1443         struct binder_ref *ref;
1444         struct rb_node *n;
1445 
1446         while (*p) {
1447                 parent = *p;
1448                 ref = rb_entry(parent, struct binder_ref, rb_node_node);
1449 
1450                 if (node < ref->node)
1451                         p = &(*p)->rb_left;
1452                 else if (node > ref->node)
1453                         p = &(*p)->rb_right;
1454                 else
1455                         return ref;
1456         }
1457         if (!new_ref)
1458                 return NULL;
1459 
1460         binder_stats_created(BINDER_STAT_REF);
1461         new_ref->data.debug_id = atomic_inc_return(&binder_last_id);
1462         new_ref->proc = proc;
1463         new_ref->node = node;
1464         rb_link_node(&new_ref->rb_node_node, parent, p);
1465         rb_insert_color(&new_ref->rb_node_node, &proc->refs_by_node);
1466 
1467         new_ref->data.desc = (node == context->binder_context_mgr_node) ? 0 : 1;
1468         for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
1469                 ref = rb_entry(n, struct binder_ref, rb_node_desc);
1470                 if (ref->data.desc > new_ref->data.desc)
1471                         break;
1472                 new_ref->data.desc = ref->data.desc + 1;
1473         }
1474 
1475         p = &proc->refs_by_desc.rb_node;
1476         while (*p) {
1477                 parent = *p;
1478                 ref = rb_entry(parent, struct binder_ref, rb_node_desc);
1479 
1480                 if (new_ref->data.desc < ref->data.desc)
1481                         p = &(*p)->rb_left;
1482                 else if (new_ref->data.desc > ref->data.desc)
1483                         p = &(*p)->rb_right;
1484                 else
1485                         BUG();
1486         }
1487         rb_link_node(&new_ref->rb_node_desc, parent, p);
1488         rb_insert_color(&new_ref->rb_node_desc, &proc->refs_by_desc);
1489 
1490         binder_node_lock(node);
1491         hlist_add_head(&new_ref->node_entry, &node->refs);
1492 
1493         binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1494                      "%d new ref %d desc %d for node %d\n",
1495                       proc->pid, new_ref->data.debug_id, new_ref->data.desc,
1496                       node->debug_id);
1497         binder_node_unlock(node);
1498         return new_ref;
1499 }
1500 
1501 static void binder_cleanup_ref_olocked(struct binder_ref *ref)
1502 {
1503         bool delete_node = false;
1504 
1505         binder_debug(BINDER_DEBUG_INTERNAL_REFS,
1506                      "%d delete ref %d desc %d for node %d\n",
1507                       ref->proc->pid, ref->data.debug_id, ref->data.desc,
1508                       ref->node->debug_id);
1509 
1510         rb_erase(&ref->rb_node_desc, &ref->proc->refs_by_desc);
1511         rb_erase(&ref->rb_node_node, &ref->proc->refs_by_node);
1512 
1513         binder_node_inner_lock(ref->node);
1514         if (ref->data.strong)
1515                 binder_dec_node_nilocked(ref->node, 1, 1);
1516 
1517         hlist_del(&ref->node_entry);
1518         delete_node = binder_dec_node_nilocked(ref->node, 0, 1);
1519         binder_node_inner_unlock(ref->node);
1520         /*
1521          * Clear ref->node unless we want the caller to free the node
1522          */
1523         if (!delete_node) {
1524                 /*
1525                  * The caller uses ref->node to determine
1526                  * whether the node needs to be freed. Clear
1527                  * it since the node is still alive.
1528                  */
1529                 ref->node = NULL;
1530         }
1531 
1532         if (ref->death) {
1533                 binder_debug(BINDER_DEBUG_DEAD_BINDER,
1534                              "%d delete ref %d desc %d has death notification\n",
1535                               ref->proc->pid, ref->data.debug_id,
1536                               ref->data.desc);
1537                 binder_dequeue_work(ref->proc, &ref->death->work);
1538                 binder_stats_deleted(BINDER_STAT_DEATH);
1539         }
1540         binder_stats_deleted(BINDER_STAT_REF);
1541 }
1542 
1543 /**
1544  * binder_inc_ref_olocked() - increment the ref for given handle
1545  * @ref:         ref to be incremented
1546  * @strong:      if true, strong increment, else weak
1547  * @target_list: list to queue node work on
1548  *
1549  * Increment the ref. @ref->proc->outer_lock must be held on entry
1550  *
1551  * Return: 0, if successful, else errno
1552  */
1553 static int binder_inc_ref_olocked(struct binder_ref *ref, int strong,
1554                                   struct list_head *target_list)
1555 {
1556         int ret;
1557 
1558         if (strong) {
1559                 if (ref->data.strong == 0) {
1560                         ret = binder_inc_node(ref->node, 1, 1, target_list);
1561                         if (ret)
1562                                 return ret;
1563                 }
1564                 ref->data.strong++;
1565         } else {
1566                 if (ref->data.weak == 0) {
1567                         ret = binder_inc_node(ref->node, 0, 1, target_list);
1568                         if (ret)
1569                                 return ret;
1570                 }
1571                 ref->data.weak++;
1572         }
1573         return 0;
1574 }
1575 
1576 /**
1577  * binder_dec_ref() - dec the ref for given handle
1578  * @ref:        ref to be decremented
1579  * @strong:     if true, strong decrement, else weak
1580  *
1581  * Decrement the ref.
1582  *
1583  * Return: true if ref is cleaned up and ready to be freed
1584  */
1585 static bool binder_dec_ref_olocked(struct binder_ref *ref, int strong)
1586 {
1587         if (strong) {
1588                 if (ref->data.strong == 0) {
1589                         binder_user_error("%d invalid dec strong, ref %d desc %d s %d w %d\n",
1590                                           ref->proc->pid, ref->data.debug_id,
1591                                           ref->data.desc, ref->data.strong,
1592                                           ref->data.weak);
1593                         return false;
1594                 }
1595                 ref->data.strong--;
1596                 if (ref->data.strong == 0)
1597                         binder_dec_node(ref->node, strong, 1);
1598         } else {
1599                 if (ref->data.weak == 0) {
1600                         binder_user_error("%d invalid dec weak, ref %d desc %d s %d w %d\n",
1601                                           ref->proc->pid, ref->data.debug_id,
1602                                           ref->data.desc, ref->data.strong,
1603                                           ref->data.weak);
1604                         return false;
1605                 }
1606                 ref->data.weak--;
1607         }
1608         if (ref->data.strong == 0 && ref->data.weak == 0) {
1609                 binder_cleanup_ref_olocked(ref);
1610                 return true;
1611         }
1612         return false;
1613 }
1614 
1615 /**
1616  * binder_get_node_from_ref() - get the node from the given proc/desc
1617  * @proc:       proc containing the ref
1618  * @desc:       the handle associated with the ref
1619  * @need_strong_ref: if true, only return node if ref is strong
1620  * @rdata:      the id/refcount data for the ref
1621  *
1622  * Given a proc and ref handle, return the associated binder_node
1623  *
1624  * Return: a binder_node or NULL if not found or not strong when strong required
1625  */
1626 static struct binder_node *binder_get_node_from_ref(
1627                 struct binder_proc *proc,
1628                 u32 desc, bool need_strong_ref,
1629                 struct binder_ref_data *rdata)
1630 {
1631         struct binder_node *node;
1632         struct binder_ref *ref;
1633 
1634         binder_proc_lock(proc);
1635         ref = binder_get_ref_olocked(proc, desc, need_strong_ref);
1636         if (!ref)
1637                 goto err_no_ref;
1638         node = ref->node;
1639         /*
1640          * Take an implicit reference on the node to ensure
1641          * it stays alive until the call to binder_put_node()
1642          */
1643         binder_inc_node_tmpref(node);
1644         if (rdata)
1645                 *rdata = ref->data;
1646         binder_proc_unlock(proc);
1647 
1648         return node;
1649 
1650 err_no_ref:
1651         binder_proc_unlock(proc);
1652         return NULL;
1653 }
1654 
1655 /**
1656  * binder_free_ref() - free the binder_ref
1657  * @ref:        ref to free
1658  *
1659  * Free the binder_ref. Free the binder_node indicated by ref->node
1660  * (if non-NULL) and the binder_ref_death indicated by ref->death.
1661  */
1662 static void binder_free_ref(struct binder_ref *ref)
1663 {
1664         if (ref->node)
1665                 binder_free_node(ref->node);
1666         kfree(ref->death);
1667         kfree(ref);
1668 }
1669 
1670 /**
1671  * binder_update_ref_for_handle() - inc/dec the ref for given handle
1672  * @proc:       proc containing the ref
1673  * @desc:       the handle associated with the ref
1674  * @increment:  true=inc reference, false=dec reference
1675  * @strong:     true=strong reference, false=weak reference
1676  * @rdata:      the id/refcount data for the ref
1677  *
1678  * Given a proc and ref handle, increment or decrement the ref
1679  * according to "increment" arg.
1680  *
1681  * Return: 0 if successful, else errno
1682  */
1683 static int binder_update_ref_for_handle(struct binder_proc *proc,
1684                 uint32_t desc, bool increment, bool strong,
1685                 struct binder_ref_data *rdata)
1686 {
1687         int ret = 0;
1688         struct binder_ref *ref;
1689         bool delete_ref = false;
1690 
1691         binder_proc_lock(proc);
1692         ref = binder_get_ref_olocked(proc, desc, strong);
1693         if (!ref) {
1694                 ret = -EINVAL;
1695                 goto err_no_ref;
1696         }
1697         if (increment)
1698                 ret = binder_inc_ref_olocked(ref, strong, NULL);
1699         else
1700                 delete_ref = binder_dec_ref_olocked(ref, strong);
1701 
1702         if (rdata)
1703                 *rdata = ref->data;
1704         binder_proc_unlock(proc);
1705 
1706         if (delete_ref)
1707                 binder_free_ref(ref);
1708         return ret;
1709 
1710 err_no_ref:
1711         binder_proc_unlock(proc);
1712         return ret;
1713 }
1714 
1715 /**
1716  * binder_dec_ref_for_handle() - dec the ref for given handle
1717  * @proc:       proc containing the ref
1718  * @desc:       the handle associated with the ref
1719  * @strong:     true=strong reference, false=weak reference
1720  * @rdata:      the id/refcount data for the ref
1721  *
1722  * Just calls binder_update_ref_for_handle() to decrement the ref.
1723  *
1724  * Return: 0 if successful, else errno
1725  */
1726 static int binder_dec_ref_for_handle(struct binder_proc *proc,
1727                 uint32_t desc, bool strong, struct binder_ref_data *rdata)
1728 {
1729         return binder_update_ref_for_handle(proc, desc, false, strong, rdata);
1730 }
1731 
1732 
1733 /**
1734  * binder_inc_ref_for_node() - increment the ref for given proc/node
1735  * @proc:        proc containing the ref
1736  * @node:        target node
1737  * @strong:      true=strong reference, false=weak reference
1738  * @target_list: worklist to use if node is incremented
1739  * @rdata:       the id/refcount data for the ref
1740  *
1741  * Given a proc and node, increment the ref. Create the ref if it
1742  * doesn't already exist
1743  *
1744  * Return: 0 if successful, else errno
1745  */
1746 static int binder_inc_ref_for_node(struct binder_proc *proc,
1747                         struct binder_node *node,
1748                         bool strong,
1749                         struct list_head *target_list,
1750                         struct binder_ref_data *rdata)
1751 {
1752         struct binder_ref *ref;
1753         struct binder_ref *new_ref = NULL;
1754         int ret = 0;
1755 
1756         binder_proc_lock(proc);
1757         ref = binder_get_ref_for_node_olocked(proc, node, NULL);
1758         if (!ref) {
1759                 binder_proc_unlock(proc);
1760                 new_ref = kzalloc(sizeof(*ref), GFP_KERNEL);
1761                 if (!new_ref)
1762                         return -ENOMEM;
1763                 binder_proc_lock(proc);
1764                 ref = binder_get_ref_for_node_olocked(proc, node, new_ref);
1765         }
1766         ret = binder_inc_ref_olocked(ref, strong, target_list);
1767         *rdata = ref->data;
1768         binder_proc_unlock(proc);
1769         if (new_ref && ref != new_ref)
1770                 /*
1771                  * Another thread created the ref first so
1772                  * free the one we allocated
1773                  */
1774                 kfree(new_ref);
1775         return ret;
1776 }
1777 
1778 static void binder_pop_transaction_ilocked(struct binder_thread *target_thread,
1779                                            struct binder_transaction *t)
1780 {
1781         BUG_ON(!target_thread);
1782         assert_spin_locked(&target_thread->proc->inner_lock);
1783         BUG_ON(target_thread->transaction_stack != t);
1784         BUG_ON(target_thread->transaction_stack->from != target_thread);
1785         target_thread->transaction_stack =
1786                 target_thread->transaction_stack->from_parent;
1787         t->from = NULL;
1788 }
1789 
1790 /**
1791  * binder_thread_dec_tmpref() - decrement thread->tmp_ref
1792  * @thread:     thread to decrement
1793  *
1794  * A thread needs to be kept alive while being used to create or
1795  * handle a transaction. binder_get_txn_from() is used to safely
1796  * extract t->from from a binder_transaction and keep the thread
1797  * indicated by t->from from being freed. When done with that
1798  * binder_thread, this function is called to decrement the
1799  * tmp_ref and free if appropriate (thread has been released
1800  * and no transaction being processed by the driver)
1801  */
1802 static void binder_thread_dec_tmpref(struct binder_thread *thread)
1803 {
1804         /*
1805          * atomic is used to protect the counter value while
1806          * it cannot reach zero or thread->is_dead is false
1807          */
1808         binder_inner_proc_lock(thread->proc);
1809         atomic_dec(&thread->tmp_ref);
1810         if (thread->is_dead && !atomic_read(&thread->tmp_ref)) {
1811                 binder_inner_proc_unlock(thread->proc);
1812                 binder_free_thread(thread);
1813                 return;
1814         }
1815         binder_inner_proc_unlock(thread->proc);
1816 }
1817 
1818 /**
1819  * binder_proc_dec_tmpref() - decrement proc->tmp_ref
1820  * @proc:       proc to decrement
1821  *
1822  * A binder_proc needs to be kept alive while being used to create or
1823  * handle a transaction. proc->tmp_ref is incremented when
1824  * creating a new transaction or the binder_proc is currently in-use
1825  * by threads that are being released. When done with the binder_proc,
1826  * this function is called to decrement the counter and free the
1827  * proc if appropriate (proc has been released, all threads have
1828  * been released and not currenly in-use to process a transaction).
1829  */
1830 static void binder_proc_dec_tmpref(struct binder_proc *proc)
1831 {
1832         binder_inner_proc_lock(proc);
1833         proc->tmp_ref--;
1834         if (proc->is_dead && RB_EMPTY_ROOT(&proc->threads) &&
1835                         !proc->tmp_ref) {
1836                 binder_inner_proc_unlock(proc);
1837                 binder_free_proc(proc);
1838                 return;
1839         }
1840         binder_inner_proc_unlock(proc);
1841 }
1842 
1843 /**
1844  * binder_get_txn_from() - safely extract the "from" thread in transaction
1845  * @t:  binder transaction for t->from
1846  *
1847  * Atomically return the "from" thread and increment the tmp_ref
1848  * count for the thread to ensure it stays alive until
1849  * binder_thread_dec_tmpref() is called.
1850  *
1851  * Return: the value of t->from
1852  */
1853 static struct binder_thread *binder_get_txn_from(
1854                 struct binder_transaction *t)
1855 {
1856         struct binder_thread *from;
1857 
1858         spin_lock(&t->lock);
1859         from = t->from;
1860         if (from)
1861                 atomic_inc(&from->tmp_ref);
1862         spin_unlock(&t->lock);
1863         return from;
1864 }
1865 
1866 /**
1867  * binder_get_txn_from_and_acq_inner() - get t->from and acquire inner lock
1868  * @t:  binder transaction for t->from
1869  *
1870  * Same as binder_get_txn_from() except it also acquires the proc->inner_lock
1871  * to guarantee that the thread cannot be released while operating on it.
1872  * The caller must call binder_inner_proc_unlock() to release the inner lock
1873  * as well as call binder_dec_thread_txn() to release the reference.
1874  *
1875  * Return: the value of t->from
1876  */
1877 static struct binder_thread *binder_get_txn_from_and_acq_inner(
1878                 struct binder_transaction *t)
1879         __acquires(&t->from->proc->inner_lock)
1880 {
1881         struct binder_thread *from;
1882 
1883         from = binder_get_txn_from(t);
1884         if (!from) {
1885                 __acquire(&from->proc->inner_lock);
1886                 return NULL;
1887         }
1888         binder_inner_proc_lock(from->proc);
1889         if (t->from) {
1890                 BUG_ON(from != t->from);
1891                 return from;
1892         }
1893         binder_inner_proc_unlock(from->proc);
1894         __acquire(&from->proc->inner_lock);
1895         binder_thread_dec_tmpref(from);
1896         return NULL;
1897 }
1898 
1899 /**
1900  * binder_free_txn_fixups() - free unprocessed fd fixups
1901  * @t:  binder transaction for t->from
1902  *
1903  * If the transaction is being torn down prior to being
1904  * processed by the target process, free all of the
1905  * fd fixups and fput the file structs. It is safe to
1906  * call this function after the fixups have been
1907  * processed -- in that case, the list will be empty.
1908  */
1909 static void binder_free_txn_fixups(struct binder_transaction *t)
1910 {
1911         struct binder_txn_fd_fixup *fixup, *tmp;
1912 
1913         list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
1914                 fput(fixup->file);
1915                 list_del(&fixup->fixup_entry);
1916                 kfree(fixup);
1917         }
1918 }
1919 
1920 static void binder_free_transaction(struct binder_transaction *t)
1921 {
1922         struct binder_proc *target_proc = t->to_proc;
1923 
1924         if (target_proc) {
1925                 binder_inner_proc_lock(target_proc);
1926                 if (t->buffer)
1927                         t->buffer->transaction = NULL;
1928                 binder_inner_proc_unlock(target_proc);
1929         }
1930         /*
1931          * If the transaction has no target_proc, then
1932          * t->buffer->transaction has already been cleared.
1933          */
1934         binder_free_txn_fixups(t);
1935         kfree(t);
1936         binder_stats_deleted(BINDER_STAT_TRANSACTION);
1937 }
1938 
1939 static void binder_send_failed_reply(struct binder_transaction *t,
1940                                      uint32_t error_code)
1941 {
1942         struct binder_thread *target_thread;
1943         struct binder_transaction *next;
1944 
1945         BUG_ON(t->flags & TF_ONE_WAY);
1946         while (1) {
1947                 target_thread = binder_get_txn_from_and_acq_inner(t);
1948                 if (target_thread) {
1949                         binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1950                                      "send failed reply for transaction %d to %d:%d\n",
1951                                       t->debug_id,
1952                                       target_thread->proc->pid,
1953                                       target_thread->pid);
1954 
1955                         binder_pop_transaction_ilocked(target_thread, t);
1956                         if (target_thread->reply_error.cmd == BR_OK) {
1957                                 target_thread->reply_error.cmd = error_code;
1958                                 binder_enqueue_thread_work_ilocked(
1959                                         target_thread,
1960                                         &target_thread->reply_error.work);
1961                                 wake_up_interruptible(&target_thread->wait);
1962                         } else {
1963                                 /*
1964                                  * Cannot get here for normal operation, but
1965                                  * we can if multiple synchronous transactions
1966                                  * are sent without blocking for responses.
1967                                  * Just ignore the 2nd error in this case.
1968                                  */
1969                                 pr_warn("Unexpected reply error: %u\n",
1970                                         target_thread->reply_error.cmd);
1971                         }
1972                         binder_inner_proc_unlock(target_thread->proc);
1973                         binder_thread_dec_tmpref(target_thread);
1974                         binder_free_transaction(t);
1975                         return;
1976                 } else {
1977                         __release(&target_thread->proc->inner_lock);
1978                 }
1979                 next = t->from_parent;
1980 
1981                 binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
1982                              "send failed reply for transaction %d, target dead\n",
1983                              t->debug_id);
1984 
1985                 binder_free_transaction(t);
1986                 if (next == NULL) {
1987                         binder_debug(BINDER_DEBUG_DEAD_BINDER,
1988                                      "reply failed, no target thread at root\n");
1989                         return;
1990                 }
1991                 t = next;
1992                 binder_debug(BINDER_DEBUG_DEAD_BINDER,
1993                              "reply failed, no target thread -- retry %d\n",
1994                               t->debug_id);
1995         }
1996 }
1997 
1998 /**
1999  * binder_cleanup_transaction() - cleans up undelivered transaction
2000  * @t:          transaction that needs to be cleaned up
2001  * @reason:     reason the transaction wasn't delivered
2002  * @error_code: error to return to caller (if synchronous call)
2003  */
2004 static void binder_cleanup_transaction(struct binder_transaction *t,
2005                                        const char *reason,
2006                                        uint32_t error_code)
2007 {
2008         if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
2009                 binder_send_failed_reply(t, error_code);
2010         } else {
2011                 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
2012                         "undelivered transaction %d, %s\n",
2013                         t->debug_id, reason);
2014                 binder_free_transaction(t);
2015         }
2016 }
2017 
2018 /**
2019  * binder_get_object() - gets object and checks for valid metadata
2020  * @proc:       binder_proc owning the buffer
2021  * @buffer:     binder_buffer that we're parsing.
2022  * @offset:     offset in the @buffer at which to validate an object.
2023  * @object:     struct binder_object to read into
2024  *
2025  * Return:      If there's a valid metadata object at @offset in @buffer, the
2026  *              size of that object. Otherwise, it returns zero. The object
2027  *              is read into the struct binder_object pointed to by @object.
2028  */
2029 static size_t binder_get_object(struct binder_proc *proc,
2030                                 struct binder_buffer *buffer,
2031                                 unsigned long offset,
2032                                 struct binder_object *object)
2033 {
2034         size_t read_size;
2035         struct binder_object_header *hdr;
2036         size_t object_size = 0;
2037 
2038         read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset);
2039         if (offset > buffer->data_size || read_size < sizeof(*hdr) ||
2040             binder_alloc_copy_from_buffer(&proc->alloc, object, buffer,
2041                                           offset, read_size))
2042                 return 0;
2043 
2044         /* Ok, now see if we read a complete object. */
2045         hdr = &object->hdr;
2046         switch (hdr->type) {
2047         case BINDER_TYPE_BINDER:
2048         case BINDER_TYPE_WEAK_BINDER:
2049         case BINDER_TYPE_HANDLE:
2050         case BINDER_TYPE_WEAK_HANDLE:
2051                 object_size = sizeof(struct flat_binder_object);
2052                 break;
2053         case BINDER_TYPE_FD:
2054                 object_size = sizeof(struct binder_fd_object);
2055                 break;
2056         case BINDER_TYPE_PTR:
2057                 object_size = sizeof(struct binder_buffer_object);
2058                 break;
2059         case BINDER_TYPE_FDA:
2060                 object_size = sizeof(struct binder_fd_array_object);
2061                 break;
2062         default:
2063                 return 0;
2064         }
2065         if (offset <= buffer->data_size - object_size &&
2066             buffer->data_size >= object_size)
2067                 return object_size;
2068         else
2069                 return 0;
2070 }
2071 
2072 /**
2073  * binder_validate_ptr() - validates binder_buffer_object in a binder_buffer.
2074  * @proc:       binder_proc owning the buffer
2075  * @b:          binder_buffer containing the object
2076  * @object:     struct binder_object to read into
2077  * @index:      index in offset array at which the binder_buffer_object is
2078  *              located
2079  * @start_offset: points to the start of the offset array
2080  * @object_offsetp: offset of @object read from @b
2081  * @num_valid:  the number of valid offsets in the offset array
2082  *
2083  * Return:      If @index is within the valid range of the offset array
2084  *              described by @start and @num_valid, and if there's a valid
2085  *              binder_buffer_object at the offset found in index @index
2086  *              of the offset array, that object is returned. Otherwise,
2087  *              %NULL is returned.
2088  *              Note that the offset found in index @index itself is not
2089  *              verified; this function assumes that @num_valid elements
2090  *              from @start were previously verified to have valid offsets.
2091  *              If @object_offsetp is non-NULL, then the offset within
2092  *              @b is written to it.
2093  */
2094 static struct binder_buffer_object *binder_validate_ptr(
2095                                                 struct binder_proc *proc,
2096                                                 struct binder_buffer *b,
2097                                                 struct binder_object *object,
2098                                                 binder_size_t index,
2099                                                 binder_size_t start_offset,
2100                                                 binder_size_t *object_offsetp,
2101                                                 binder_size_t num_valid)
2102 {
2103         size_t object_size;
2104         binder_size_t object_offset;
2105         unsigned long buffer_offset;
2106 
2107         if (index >= num_valid)
2108                 return NULL;
2109 
2110         buffer_offset = start_offset + sizeof(binder_size_t) * index;
2111         if (binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
2112                                           b, buffer_offset,
2113                                           sizeof(object_offset)))
2114                 return NULL;
2115         object_size = binder_get_object(proc, b, object_offset, object);
2116         if (!object_size || object->hdr.type != BINDER_TYPE_PTR)
2117                 return NULL;
2118         if (object_offsetp)
2119                 *object_offsetp = object_offset;
2120 
2121         return &object->bbo;
2122 }
2123 
2124 /**
2125  * binder_validate_fixup() - validates pointer/fd fixups happen in order.
2126  * @proc:               binder_proc owning the buffer
2127  * @b:                  transaction buffer
2128  * @objects_start_offset: offset to start of objects buffer
2129  * @buffer_obj_offset:  offset to binder_buffer_object in which to fix up
2130  * @fixup_offset:       start offset in @buffer to fix up
2131  * @last_obj_offset:    offset to last binder_buffer_object that we fixed
2132  * @last_min_offset:    minimum fixup offset in object at @last_obj_offset
2133  *
2134  * Return:              %true if a fixup in buffer @buffer at offset @offset is
2135  *                      allowed.
2136  *
2137  * For safety reasons, we only allow fixups inside a buffer to happen
2138  * at increasing offsets; additionally, we only allow fixup on the last
2139  * buffer object that was verified, or one of its parents.
2140  *
2141  * Example of what is allowed:
2142  *
2143  * A
2144  *   B (parent = A, offset = 0)
2145  *   C (parent = A, offset = 16)
2146  *     D (parent = C, offset = 0)
2147  *   E (parent = A, offset = 32) // min_offset is 16 (C.parent_offset)
2148  *
2149  * Examples of what is not allowed:
2150  *
2151  * Decreasing offsets within the same parent:
2152  * A
2153  *   C (parent = A, offset = 16)
2154  *   B (parent = A, offset = 0) // decreasing offset within A
2155  *
2156  * Referring to a parent that wasn't the last object or any of its parents:
2157  * A
2158  *   B (parent = A, offset = 0)
2159  *   C (parent = A, offset = 0)
2160  *   C (parent = A, offset = 16)
2161  *     D (parent = B, offset = 0) // B is not A or any of A's parents
2162  */
2163 static bool binder_validate_fixup(struct binder_proc *proc,
2164                                   struct binder_buffer *b,
2165                                   binder_size_t objects_start_offset,
2166                                   binder_size_t buffer_obj_offset,
2167                                   binder_size_t fixup_offset,
2168                                   binder_size_t last_obj_offset,
2169                                   binder_size_t last_min_offset)
2170 {
2171         if (!last_obj_offset) {
2172                 /* Nothing to fix up in */
2173                 return false;
2174         }
2175 
2176         while (last_obj_offset != buffer_obj_offset) {
2177                 unsigned long buffer_offset;
2178                 struct binder_object last_object;
2179                 struct binder_buffer_object *last_bbo;
2180                 size_t object_size = binder_get_object(proc, b, last_obj_offset,
2181                                                        &last_object);
2182                 if (object_size != sizeof(*last_bbo))
2183                         return false;
2184 
2185                 last_bbo = &last_object.bbo;
2186                 /*
2187                  * Safe to retrieve the parent of last_obj, since it
2188                  * was already previously verified by the driver.
2189                  */
2190                 if ((last_bbo->flags & BINDER_BUFFER_FLAG_HAS_PARENT) == 0)
2191                         return false;
2192                 last_min_offset = last_bbo->parent_offset + sizeof(uintptr_t);
2193                 buffer_offset = objects_start_offset +
2194                         sizeof(binder_size_t) * last_bbo->parent;
2195                 if (binder_alloc_copy_from_buffer(&proc->alloc,
2196                                                   &last_obj_offset,
2197                                                   b, buffer_offset,
2198                                                   sizeof(last_obj_offset)))
2199                         return false;
2200         }
2201         return (fixup_offset >= last_min_offset);
2202 }
2203 
2204 /**
2205  * struct binder_task_work_cb - for deferred close
2206  *
2207  * @twork:                callback_head for task work
2208  * @fd:                   fd to close
2209  *
2210  * Structure to pass task work to be handled after
2211  * returning from binder_ioctl() via task_work_add().
2212  */
2213 struct binder_task_work_cb {
2214         struct callback_head twork;
2215         struct file *file;
2216 };
2217 
2218 /**
2219  * binder_do_fd_close() - close list of file descriptors
2220  * @twork:      callback head for task work
2221  *
2222  * It is not safe to call ksys_close() during the binder_ioctl()
2223  * function if there is a chance that binder's own file descriptor
2224  * might be closed. This is to meet the requirements for using
2225  * fdget() (see comments for __fget_light()). Therefore use
2226  * task_work_add() to schedule the close operation once we have
2227  * returned from binder_ioctl(). This function is a callback
2228  * for that mechanism and does the actual ksys_close() on the
2229  * given file descriptor.
2230  */
2231 static void binder_do_fd_close(struct callback_head *twork)
2232 {
2233         struct binder_task_work_cb *twcb = container_of(twork,
2234                         struct binder_task_work_cb, twork);
2235 
2236         fput(twcb->file);
2237         kfree(twcb);
2238 }
2239 
2240 /**
2241  * binder_deferred_fd_close() - schedule a close for the given file-descriptor
2242  * @fd:         file-descriptor to close
2243  *
2244  * See comments in binder_do_fd_close(). This function is used to schedule
2245  * a file-descriptor to be closed after returning from binder_ioctl().
2246  */
2247 static void binder_deferred_fd_close(int fd)
2248 {
2249         struct binder_task_work_cb *twcb;
2250 
2251         twcb = kzalloc(sizeof(*twcb), GFP_KERNEL);
2252         if (!twcb)
2253                 return;
2254         init_task_work(&twcb->twork, binder_do_fd_close);
2255         __close_fd_get_file(fd, &twcb->file);
2256         if (twcb->file)
2257                 task_work_add(current, &twcb->twork, true);
2258         else
2259                 kfree(twcb);
2260 }
2261 
2262 static void binder_transaction_buffer_release(struct binder_proc *proc,
2263                                               struct binder_buffer *buffer,
2264                                               binder_size_t failed_at,
2265                                               bool is_failure)
2266 {
2267         int debug_id = buffer->debug_id;
2268         binder_size_t off_start_offset, buffer_offset, off_end_offset;
2269 
2270         binder_debug(BINDER_DEBUG_TRANSACTION,
2271                      "%d buffer release %d, size %zd-%zd, failed at %llx\n",
2272                      proc->pid, buffer->debug_id,
2273                      buffer->data_size, buffer->offsets_size,
2274                      (unsigned long long)failed_at);
2275 
2276         if (buffer->target_node)
2277                 binder_dec_node(buffer->target_node, 1, 0);
2278 
2279         off_start_offset = ALIGN(buffer->data_size, sizeof(void *));
2280         off_end_offset = is_failure ? failed_at :
2281                                 off_start_offset + buffer->offsets_size;
2282         for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
2283              buffer_offset += sizeof(binder_size_t)) {
2284                 struct binder_object_header *hdr;
2285                 size_t object_size = 0;
2286                 struct binder_object object;
2287                 binder_size_t object_offset;
2288 
2289                 if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset,
2290                                                    buffer, buffer_offset,
2291                                                    sizeof(object_offset)))
2292                         object_size = binder_get_object(proc, buffer,
2293                                                         object_offset, &object);
2294                 if (object_size == 0) {
2295                         pr_err("transaction release %d bad object at offset %lld, size %zd\n",
2296                                debug_id, (u64)object_offset, buffer->data_size);
2297                         continue;
2298                 }
2299                 hdr = &object.hdr;
2300                 switch (hdr->type) {
2301                 case BINDER_TYPE_BINDER:
2302                 case BINDER_TYPE_WEAK_BINDER: {
2303                         struct flat_binder_object *fp;
2304                         struct binder_node *node;
2305 
2306                         fp = to_flat_binder_object(hdr);
2307                         node = binder_get_node(proc, fp->binder);
2308                         if (node == NULL) {
2309                                 pr_err("transaction release %d bad node %016llx\n",
2310                                        debug_id, (u64)fp->binder);
2311                                 break;
2312                         }
2313                         binder_debug(BINDER_DEBUG_TRANSACTION,
2314                                      "        node %d u%016llx\n",
2315                                      node->debug_id, (u64)node->ptr);
2316                         binder_dec_node(node, hdr->type == BINDER_TYPE_BINDER,
2317                                         0);
2318                         binder_put_node(node);
2319                 } break;
2320                 case BINDER_TYPE_HANDLE:
2321                 case BINDER_TYPE_WEAK_HANDLE: {
2322                         struct flat_binder_object *fp;
2323                         struct binder_ref_data rdata;
2324                         int ret;
2325 
2326                         fp = to_flat_binder_object(hdr);
2327                         ret = binder_dec_ref_for_handle(proc, fp->handle,
2328                                 hdr->type == BINDER_TYPE_HANDLE, &rdata);
2329 
2330                         if (ret) {
2331                                 pr_err("transaction release %d bad handle %d, ret = %d\n",
2332                                  debug_id, fp->handle, ret);
2333                                 break;
2334                         }
2335                         binder_debug(BINDER_DEBUG_TRANSACTION,
2336                                      "        ref %d desc %d\n",
2337                                      rdata.debug_id, rdata.desc);
2338                 } break;
2339 
2340                 case BINDER_TYPE_FD: {
2341                         /*
2342                          * No need to close the file here since user-space
2343                          * closes it for for successfully delivered
2344                          * transactions. For transactions that weren't
2345                          * delivered, the new fd was never allocated so
2346                          * there is no need to close and the fput on the
2347                          * file is done when the transaction is torn
2348                          * down.
2349                          */
2350                         WARN_ON(failed_at &&
2351                                 proc->tsk == current->group_leader);
2352                 } break;
2353                 case BINDER_TYPE_PTR:
2354                         /*
2355                          * Nothing to do here, this will get cleaned up when the
2356                          * transaction buffer gets freed
2357                          */
2358                         break;
2359                 case BINDER_TYPE_FDA: {
2360                         struct binder_fd_array_object *fda;
2361                         struct binder_buffer_object *parent;
2362                         struct binder_object ptr_object;
2363                         binder_size_t fda_offset;
2364                         size_t fd_index;
2365                         binder_size_t fd_buf_size;
2366                         binder_size_t num_valid;
2367 
2368                         if (proc->tsk != current->group_leader) {
2369                                 /*
2370                                  * Nothing to do if running in sender context
2371                                  * The fd fixups have not been applied so no
2372                                  * fds need to be closed.
2373                                  */
2374                                 continue;
2375                         }
2376 
2377                         num_valid = (buffer_offset - off_start_offset) /
2378                                                 sizeof(binder_size_t);
2379                         fda = to_binder_fd_array_object(hdr);
2380                         parent = binder_validate_ptr(proc, buffer, &ptr_object,
2381                                                      fda->parent,
2382                                                      off_start_offset,
2383                                                      NULL,
2384                                                      num_valid);
2385                         if (!parent) {
2386                                 pr_err("transaction release %d bad parent offset\n",
2387                                        debug_id);
2388                                 continue;
2389                         }
2390                         fd_buf_size = sizeof(u32) * fda->num_fds;
2391                         if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2392                                 pr_err("transaction release %d invalid number of fds (%lld)\n",
2393                                        debug_id, (u64)fda->num_fds);
2394                                 continue;
2395                         }
2396                         if (fd_buf_size > parent->length ||
2397                             fda->parent_offset > parent->length - fd_buf_size) {
2398                                 /* No space for all file descriptors here. */
2399                                 pr_err("transaction release %d not enough space for %lld fds in buffer\n",
2400                                        debug_id, (u64)fda->num_fds);
2401                                 continue;
2402                         }
2403                         /*
2404                          * the source data for binder_buffer_object is visible
2405                          * to user-space and the @buffer element is the user
2406                          * pointer to the buffer_object containing the fd_array.
2407                          * Convert the address to an offset relative to
2408                          * the base of the transaction buffer.
2409                          */
2410                         fda_offset =
2411                             (parent->buffer - (uintptr_t)buffer->user_data) +
2412                             fda->parent_offset;
2413                         for (fd_index = 0; fd_index < fda->num_fds;
2414                              fd_index++) {
2415                                 u32 fd;
2416                                 int err;
2417                                 binder_size_t offset = fda_offset +
2418                                         fd_index * sizeof(fd);
2419 
2420                                 err = binder_alloc_copy_from_buffer(
2421                                                 &proc->alloc, &fd, buffer,
2422                                                 offset, sizeof(fd));
2423                                 WARN_ON(err);
2424                                 if (!err)
2425                                         binder_deferred_fd_close(fd);
2426                         }
2427                 } break;
2428                 default:
2429                         pr_err("transaction release %d bad object type %x\n",
2430                                 debug_id, hdr->type);
2431                         break;
2432                 }
2433         }
2434 }
2435 
2436 static int binder_translate_binder(struct flat_binder_object *fp,
2437                                    struct binder_transaction *t,
2438                                    struct binder_thread *thread)
2439 {
2440         struct binder_node *node;
2441         struct binder_proc *proc = thread->proc;
2442         struct binder_proc *target_proc = t->to_proc;
2443         struct binder_ref_data rdata;
2444         int ret = 0;
2445 
2446         node = binder_get_node(proc, fp->binder);
2447         if (!node) {
2448                 node = binder_new_node(proc, fp);
2449                 if (!node)
2450                         return -ENOMEM;
2451         }
2452         if (fp->cookie != node->cookie) {
2453                 binder_user_error("%d:%d sending u%016llx node %d, cookie mismatch %016llx != %016llx\n",
2454                                   proc->pid, thread->pid, (u64)fp->binder,
2455                                   node->debug_id, (u64)fp->cookie,
2456                                   (u64)node->cookie);
2457                 ret = -EINVAL;
2458                 goto done;
2459         }
2460         if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) {
2461                 ret = -EPERM;
2462                 goto done;
2463         }
2464 
2465         ret = binder_inc_ref_for_node(target_proc, node,
2466                         fp->hdr.type == BINDER_TYPE_BINDER,
2467                         &thread->todo, &rdata);
2468         if (ret)
2469                 goto done;
2470 
2471         if (fp->hdr.type == BINDER_TYPE_BINDER)
2472                 fp->hdr.type = BINDER_TYPE_HANDLE;
2473         else
2474                 fp->hdr.type = BINDER_TYPE_WEAK_HANDLE;
2475         fp->binder = 0;
2476         fp->handle = rdata.desc;
2477         fp->cookie = 0;
2478 
2479         trace_binder_transaction_node_to_ref(t, node, &rdata);
2480         binder_debug(BINDER_DEBUG_TRANSACTION,
2481                      "        node %d u%016llx -> ref %d desc %d\n",
2482                      node->debug_id, (u64)node->ptr,
2483                      rdata.debug_id, rdata.desc);
2484 done:
2485         binder_put_node(node);
2486         return ret;
2487 }
2488 
2489 static int binder_translate_handle(struct flat_binder_object *fp,
2490                                    struct binder_transaction *t,
2491                                    struct binder_thread *thread)
2492 {
2493         struct binder_proc *proc = thread->proc;
2494         struct binder_proc *target_proc = t->to_proc;
2495         struct binder_node *node;
2496         struct binder_ref_data src_rdata;
2497         int ret = 0;
2498 
2499         node = binder_get_node_from_ref(proc, fp->handle,
2500                         fp->hdr.type == BINDER_TYPE_HANDLE, &src_rdata);
2501         if (!node) {
2502                 binder_user_error("%d:%d got transaction with invalid handle, %d\n",
2503                                   proc->pid, thread->pid, fp->handle);
2504                 return -EINVAL;
2505         }
2506         if (security_binder_transfer_binder(proc->tsk, target_proc->tsk)) {
2507                 ret = -EPERM;
2508                 goto done;
2509         }
2510 
2511         binder_node_lock(node);
2512         if (node->proc == target_proc) {
2513                 if (fp->hdr.type == BINDER_TYPE_HANDLE)
2514                         fp->hdr.type = BINDER_TYPE_BINDER;
2515                 else
2516                         fp->hdr.type = BINDER_TYPE_WEAK_BINDER;
2517                 fp->binder = node->ptr;
2518                 fp->cookie = node->cookie;
2519                 if (node->proc)
2520                         binder_inner_proc_lock(node->proc);
2521                 else
2522                         __acquire(&node->proc->inner_lock);
2523                 binder_inc_node_nilocked(node,
2524                                          fp->hdr.type == BINDER_TYPE_BINDER,
2525                                          0, NULL);
2526                 if (node->proc)
2527                         binder_inner_proc_unlock(node->proc);
2528                 else
2529                         __release(&node->proc->inner_lock);
2530                 trace_binder_transaction_ref_to_node(t, node, &src_rdata);
2531                 binder_debug(BINDER_DEBUG_TRANSACTION,
2532                              "        ref %d desc %d -> node %d u%016llx\n",
2533                              src_rdata.debug_id, src_rdata.desc, node->debug_id,
2534                              (u64)node->ptr);
2535                 binder_node_unlock(node);
2536         } else {
2537                 struct binder_ref_data dest_rdata;
2538 
2539                 binder_node_unlock(node);
2540                 ret = binder_inc_ref_for_node(target_proc, node,
2541                                 fp->hdr.type == BINDER_TYPE_HANDLE,
2542                                 NULL, &dest_rdata);
2543                 if (ret)
2544                         goto done;
2545 
2546                 fp->binder = 0;
2547                 fp->handle = dest_rdata.desc;
2548                 fp->cookie = 0;
2549                 trace_binder_transaction_ref_to_ref(t, node, &src_rdata,
2550                                                     &dest_rdata);
2551                 binder_debug(BINDER_DEBUG_TRANSACTION,
2552                              "        ref %d desc %d -> ref %d desc %d (node %d)\n",
2553                              src_rdata.debug_id, src_rdata.desc,
2554                              dest_rdata.debug_id, dest_rdata.desc,
2555                              node->debug_id);
2556         }
2557 done:
2558         binder_put_node(node);
2559         return ret;
2560 }
2561 
2562 static int binder_translate_fd(u32 fd, binder_size_t fd_offset,
2563                                struct binder_transaction *t,
2564                                struct binder_thread *thread,
2565                                struct binder_transaction *in_reply_to)
2566 {
2567         struct binder_proc *proc = thread->proc;
2568         struct binder_proc *target_proc = t->to_proc;
2569         struct binder_txn_fd_fixup *fixup;
2570         struct file *file;
2571         int ret = 0;
2572         bool target_allows_fd;
2573 
2574         if (in_reply_to)
2575                 target_allows_fd = !!(in_reply_to->flags & TF_ACCEPT_FDS);
2576         else
2577                 target_allows_fd = t->buffer->target_node->accept_fds;
2578         if (!target_allows_fd) {
2579                 binder_user_error("%d:%d got %s with fd, %d, but target does not allow fds\n",
2580                                   proc->pid, thread->pid,
2581                                   in_reply_to ? "reply" : "transaction",
2582                                   fd);
2583                 ret = -EPERM;
2584                 goto err_fd_not_accepted;
2585         }
2586 
2587         file = fget(fd);
2588         if (!file) {
2589                 binder_user_error("%d:%d got transaction with invalid fd, %d\n",
2590                                   proc->pid, thread->pid, fd);
2591                 ret = -EBADF;
2592                 goto err_fget;
2593         }
2594         ret = security_binder_transfer_file(proc->tsk, target_proc->tsk, file);
2595         if (ret < 0) {
2596                 ret = -EPERM;
2597                 goto err_security;
2598         }
2599 
2600         /*
2601          * Add fixup record for this transaction. The allocation
2602          * of the fd in the target needs to be done from a
2603          * target thread.
2604          */
2605         fixup = kzalloc(sizeof(*fixup), GFP_KERNEL);
2606         if (!fixup) {
2607                 ret = -ENOMEM;
2608                 goto err_alloc;
2609         }
2610         fixup->file = file;
2611         fixup->offset = fd_offset;
2612         trace_binder_transaction_fd_send(t, fd, fixup->offset);
2613         list_add_tail(&fixup->fixup_entry, &t->fd_fixups);
2614 
2615         return ret;
2616 
2617 err_alloc:
2618 err_security:
2619         fput(file);
2620 err_fget:
2621 err_fd_not_accepted:
2622         return ret;
2623 }
2624 
2625 static int binder_translate_fd_array(struct binder_fd_array_object *fda,
2626                                      struct binder_buffer_object *parent,
2627                                      struct binder_transaction *t,
2628                                      struct binder_thread *thread,
2629                                      struct binder_transaction *in_reply_to)
2630 {
2631         binder_size_t fdi, fd_buf_size;
2632         binder_size_t fda_offset;
2633         struct binder_proc *proc = thread->proc;
2634         struct binder_proc *target_proc = t->to_proc;
2635 
2636         fd_buf_size = sizeof(u32) * fda->num_fds;
2637         if (fda->num_fds >= SIZE_MAX / sizeof(u32)) {
2638                 binder_user_error("%d:%d got transaction with invalid number of fds (%lld)\n",
2639                                   proc->pid, thread->pid, (u64)fda->num_fds);
2640                 return -EINVAL;
2641         }
2642         if (fd_buf_size > parent->length ||
2643             fda->parent_offset > parent->length - fd_buf_size) {
2644                 /* No space for all file descriptors here. */
2645                 binder_user_error("%d:%d not enough space to store %lld fds in buffer\n",
2646                                   proc->pid, thread->pid, (u64)fda->num_fds);
2647                 return -EINVAL;
2648         }
2649         /*
2650          * the source data for binder_buffer_object is visible
2651          * to user-space and the @buffer element is the user
2652          * pointer to the buffer_object containing the fd_array.
2653          * Convert the address to an offset relative to
2654          * the base of the transaction buffer.
2655          */
2656         fda_offset = (parent->buffer - (uintptr_t)t->buffer->user_data) +
2657                 fda->parent_offset;
2658         if (!IS_ALIGNED((unsigned long)fda_offset, sizeof(u32))) {
2659                 binder_user_error("%d:%d parent offset not aligned correctly.\n",
2660                                   proc->pid, thread->pid);
2661                 return -EINVAL;
2662         }
2663         for (fdi = 0; fdi < fda->num_fds; fdi++) {
2664                 u32 fd;
2665                 int ret;
2666                 binder_size_t offset = fda_offset + fdi * sizeof(fd);
2667 
2668                 ret = binder_alloc_copy_from_buffer(&target_proc->alloc,
2669                                                     &fd, t->buffer,
2670                                                     offset, sizeof(fd));
2671                 if (!ret)
2672                         ret = binder_translate_fd(fd, offset, t, thread,
2673                                                   in_reply_to);
2674                 if (ret < 0)
2675                         return ret;
2676         }
2677         return 0;
2678 }
2679 
2680 static int binder_fixup_parent(struct binder_transaction *t,
2681                                struct binder_thread *thread,
2682                                struct binder_buffer_object *bp,
2683                                binder_size_t off_start_offset,
2684                                binder_size_t num_valid,
2685                                binder_size_t last_fixup_obj_off,
2686                                binder_size_t last_fixup_min_off)
2687 {
2688         struct binder_buffer_object *parent;
2689         struct binder_buffer *b = t->buffer;
2690         struct binder_proc *proc = thread->proc;
2691         struct binder_proc *target_proc = t->to_proc;
2692         struct binder_object object;
2693         binder_size_t buffer_offset;
2694         binder_size_t parent_offset;
2695 
2696         if (!(bp->flags & BINDER_BUFFER_FLAG_HAS_PARENT))
2697                 return 0;
2698 
2699         parent = binder_validate_ptr(target_proc, b, &object, bp->parent,
2700                                      off_start_offset, &parent_offset,
2701                                      num_valid);
2702         if (!parent) {
2703                 binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
2704                                   proc->pid, thread->pid);
2705                 return -EINVAL;
2706         }
2707 
2708         if (!binder_validate_fixup(target_proc, b, off_start_offset,
2709                                    parent_offset, bp->parent_offset,
2710                                    last_fixup_obj_off,
2711                                    last_fixup_min_off)) {
2712                 binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
2713                                   proc->pid, thread->pid);
2714                 return -EINVAL;
2715         }
2716 
2717         if (parent->length < sizeof(binder_uintptr_t) ||
2718             bp->parent_offset > parent->length - sizeof(binder_uintptr_t)) {
2719                 /* No space for a pointer here! */
2720                 binder_user_error("%d:%d got transaction with invalid parent offset\n",
2721                                   proc->pid, thread->pid);
2722                 return -EINVAL;
2723         }
2724         buffer_offset = bp->parent_offset +
2725                         (uintptr_t)parent->buffer - (uintptr_t)b->user_data;
2726         if (binder_alloc_copy_to_buffer(&target_proc->alloc, b, buffer_offset,
2727                                         &bp->buffer, sizeof(bp->buffer))) {
2728                 binder_user_error("%d:%d got transaction with invalid parent offset\n",
2729                                   proc->pid, thread->pid);
2730                 return -EINVAL;
2731         }
2732 
2733         return 0;
2734 }
2735 
2736 /**
2737  * binder_proc_transaction() - sends a transaction to a process and wakes it up
2738  * @t:          transaction to send
2739  * @proc:       process to send the transaction to
2740  * @thread:     thread in @proc to send the transaction to (may be NULL)
2741  *
2742  * This function queues a transaction to the specified process. It will try
2743  * to find a thread in the target process to handle the transaction and
2744  * wake it up. If no thread is found, the work is queued to the proc
2745  * waitqueue.
2746  *
2747  * If the @thread parameter is not NULL, the transaction is always queued
2748  * to the waitlist of that specific thread.
2749  *
2750  * Return:      true if the transactions was successfully queued
2751  *              false if the target process or thread is dead
2752  */
2753 static bool binder_proc_transaction(struct binder_transaction *t,
2754                                     struct binder_proc *proc,
2755                                     struct binder_thread *thread)
2756 {
2757         struct binder_node *node = t->buffer->target_node;
2758         bool oneway = !!(t->flags & TF_ONE_WAY);
2759         bool pending_async = false;
2760 
2761         BUG_ON(!node);
2762         binder_node_lock(node);
2763         if (oneway) {
2764                 BUG_ON(thread);
2765                 if (node->has_async_transaction) {
2766                         pending_async = true;
2767                 } else {
2768                         node->has_async_transaction = true;
2769                 }
2770         }
2771 
2772         binder_inner_proc_lock(proc);
2773 
2774         if (proc->is_dead || (thread && thread->is_dead)) {
2775                 binder_inner_proc_unlock(proc);
2776                 binder_node_unlock(node);
2777                 return false;
2778         }
2779 
2780         if (!thread && !pending_async)
2781                 thread = binder_select_thread_ilocked(proc);
2782 
2783         if (thread)
2784                 binder_enqueue_thread_work_ilocked(thread, &t->work);
2785         else if (!pending_async)
2786                 binder_enqueue_work_ilocked(&t->work, &proc->todo);
2787         else
2788                 binder_enqueue_work_ilocked(&t->work, &node->async_todo);
2789 
2790         if (!pending_async)
2791                 binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */);
2792 
2793         binder_inner_proc_unlock(proc);
2794         binder_node_unlock(node);
2795 
2796         return true;
2797 }
2798 
2799 /**
2800  * binder_get_node_refs_for_txn() - Get required refs on node for txn
2801  * @node:         struct binder_node for which to get refs
2802  * @proc:         returns @node->proc if valid
2803  * @error:        if no @proc then returns BR_DEAD_REPLY
2804  *
2805  * User-space normally keeps the node alive when creating a transaction
2806  * since it has a reference to the target. The local strong ref keeps it
2807  * alive if the sending process dies before the target process processes
2808  * the transaction. If the source process is malicious or has a reference
2809  * counting bug, relying on the local strong ref can fail.
2810  *
2811  * Since user-space can cause the local strong ref to go away, we also take
2812  * a tmpref on the node to ensure it survives while we are constructing
2813  * the transaction. We also need a tmpref on the proc while we are
2814  * constructing the transaction, so we take that here as well.
2815  *
2816  * Return: The target_node with refs taken or NULL if no @node->proc is NULL.
2817  * Also sets @proc if valid. If the @node->proc is NULL indicating that the
2818  * target proc has died, @error is set to BR_DEAD_REPLY
2819  */
2820 static struct binder_node *binder_get_node_refs_for_txn(
2821                 struct binder_node *node,
2822                 struct binder_proc **procp,
2823                 uint32_t *error)
2824 {
2825         struct binder_node *target_node = NULL;
2826 
2827         binder_node_inner_lock(node);
2828         if (node->proc) {
2829                 target_node = node;
2830                 binder_inc_node_nilocked(node, 1, 0, NULL);
2831                 binder_inc_node_tmpref_ilocked(node);
2832                 node->proc->tmp_ref++;
2833                 *procp = node->proc;
2834         } else
2835                 *error = BR_DEAD_REPLY;
2836         binder_node_inner_unlock(node);
2837 
2838         return target_node;
2839 }
2840 
2841 static void binder_transaction(struct binder_proc *proc,
2842                                struct binder_thread *thread,
2843                                struct binder_transaction_data *tr, int reply,
2844                                binder_size_t extra_buffers_size)
2845 {
2846         int ret;
2847         struct binder_transaction *t;
2848         struct binder_work *w;
2849         struct binder_work *tcomplete;
2850         binder_size_t buffer_offset = 0;
2851         binder_size_t off_start_offset, off_end_offset;
2852         binder_size_t off_min;
2853         binder_size_t sg_buf_offset, sg_buf_end_offset;
2854         struct binder_proc *target_proc = NULL;
2855         struct binder_thread *target_thread = NULL;
2856         struct binder_node *target_node = NULL;
2857         struct binder_transaction *in_reply_to = NULL;
2858         struct binder_transaction_log_entry *e;
2859         uint32_t return_error = 0;
2860         uint32_t return_error_param = 0;
2861         uint32_t return_error_line = 0;
2862         binder_size_t last_fixup_obj_off = 0;
2863         binder_size_t last_fixup_min_off = 0;
2864         struct binder_context *context = proc->context;
2865         int t_debug_id = atomic_inc_return(&binder_last_id);
2866         char *secctx = NULL;
2867         u32 secctx_sz = 0;
2868 
2869         e = binder_transaction_log_add(&binder_transaction_log);
2870         e->debug_id = t_debug_id;
2871         e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
2872         e->from_proc = proc->pid;
2873         e->from_thread = thread->pid;
2874         e->target_handle = tr->target.handle;
2875         e->data_size = tr->data_size;
2876         e->offsets_size = tr->offsets_size;
2877         strscpy(e->context_name, proc->context->name, BINDERFS_MAX_NAME);
2878 
2879         if (reply) {
2880                 binder_inner_proc_lock(proc);
2881                 in_reply_to = thread->transaction_stack;
2882                 if (in_reply_to == NULL) {
2883                         binder_inner_proc_unlock(proc);
2884                         binder_user_error("%d:%d got reply transaction with no transaction stack\n",
2885                                           proc->pid, thread->pid);
2886                         return_error = BR_FAILED_REPLY;
2887                         return_error_param = -EPROTO;
2888                         return_error_line = __LINE__;
2889                         goto err_empty_call_stack;
2890                 }
2891                 if (in_reply_to->to_thread != thread) {
2892                         spin_lock(&in_reply_to->lock);
2893                         binder_user_error("%d:%d got reply transaction with bad transaction stack, transaction %d has target %d:%d\n",
2894                                 proc->pid, thread->pid, in_reply_to->debug_id,
2895                                 in_reply_to->to_proc ?
2896                                 in_reply_to->to_proc->pid : 0,
2897                                 in_reply_to->to_thread ?
2898                                 in_reply_to->to_thread->pid : 0);
2899                         spin_unlock(&in_reply_to->lock);
2900                         binder_inner_proc_unlock(proc);
2901                         return_error = BR_FAILED_REPLY;
2902                         return_error_param = -EPROTO;
2903                         return_error_line = __LINE__;
2904                         in_reply_to = NULL;
2905                         goto err_bad_call_stack;
2906                 }
2907                 thread->transaction_stack = in_reply_to->to_parent;
2908                 binder_inner_proc_unlock(proc);
2909                 binder_set_nice(in_reply_to->saved_priority);
2910                 target_thread = binder_get_txn_from_and_acq_inner(in_reply_to);
2911                 if (target_thread == NULL) {
2912                         /* annotation for sparse */
2913                         __release(&target_thread->proc->inner_lock);
2914                         return_error = BR_DEAD_REPLY;
2915                         return_error_line = __LINE__;
2916                         goto err_dead_binder;
2917                 }
2918                 if (target_thread->transaction_stack != in_reply_to) {
2919                         binder_user_error("%d:%d got reply transaction with bad target transaction stack %d, expected %d\n",
2920                                 proc->pid, thread->pid,
2921                                 target_thread->transaction_stack ?
2922                                 target_thread->transaction_stack->debug_id : 0,
2923                                 in_reply_to->debug_id);
2924                         binder_inner_proc_unlock(target_thread->proc);
2925                         return_error = BR_FAILED_REPLY;
2926                         return_error_param = -EPROTO;
2927                         return_error_line = __LINE__;
2928                         in_reply_to = NULL;
2929                         target_thread = NULL;
2930                         goto err_dead_binder;
2931                 }
2932                 target_proc = target_thread->proc;
2933                 target_proc->tmp_ref++;
2934                 binder_inner_proc_unlock(target_thread->proc);
2935         } else {
2936                 if (tr->target.handle) {
2937                         struct binder_ref *ref;
2938 
2939                         /*
2940                          * There must already be a strong ref
2941                          * on this node. If so, do a strong
2942                          * increment on the node to ensure it
2943                          * stays alive until the transaction is
2944                          * done.
2945                          */
2946                         binder_proc_lock(proc);
2947                         ref = binder_get_ref_olocked(proc, tr->target.handle,
2948                                                      true);
2949                         if (ref) {
2950                                 target_node = binder_get_node_refs_for_txn(
2951                                                 ref->node, &target_proc,
2952                                                 &return_error);
2953                         } else {
2954                                 binder_user_error("%d:%d got transaction to invalid handle\n",
2955                                                   proc->pid, thread->pid);
2956                                 return_error = BR_FAILED_REPLY;
2957                         }
2958                         binder_proc_unlock(proc);
2959                 } else {
2960                         mutex_lock(&context->context_mgr_node_lock);
2961                         target_node = context->binder_context_mgr_node;
2962                         if (target_node)
2963                                 target_node = binder_get_node_refs_for_txn(
2964                                                 target_node, &target_proc,
2965                                                 &return_error);
2966                         else
2967                                 return_error = BR_DEAD_REPLY;
2968                         mutex_unlock(&context->context_mgr_node_lock);
2969                         if (target_node && target_proc->pid == proc->pid) {
2970                                 binder_user_error("%d:%d got transaction to context manager from process owning it\n",
2971                                                   proc->pid, thread->pid);
2972                                 return_error = BR_FAILED_REPLY;
2973                                 return_error_param = -EINVAL;
2974                                 return_error_line = __LINE__;
2975                                 goto err_invalid_target_handle;
2976                         }
2977                 }
2978                 if (!target_node) {
2979                         /*
2980                          * return_error is set above
2981                          */
2982                         return_error_param = -EINVAL;
2983                         return_error_line = __LINE__;
2984                         goto err_dead_binder;
2985                 }
2986                 e->to_node = target_node->debug_id;
2987                 if (security_binder_transaction(proc->tsk,
2988                                                 target_proc->tsk) < 0) {
2989                         return_error = BR_FAILED_REPLY;
2990                         return_error_param = -EPERM;
2991                         return_error_line = __LINE__;
2992                         goto err_invalid_target_handle;
2993                 }
2994                 binder_inner_proc_lock(proc);
2995 
2996                 w = list_first_entry_or_null(&thread->todo,
2997                                              struct binder_work, entry);
2998                 if (!(tr->flags & TF_ONE_WAY) && w &&
2999                     w->type == BINDER_WORK_TRANSACTION) {
3000                         /*
3001                          * Do not allow new outgoing transaction from a
3002                          * thread that has a transaction at the head of
3003                          * its todo list. Only need to check the head
3004                          * because binder_select_thread_ilocked picks a
3005                          * thread from proc->waiting_threads to enqueue
3006                          * the transaction, and nothing is queued to the
3007                          * todo list while the thread is on waiting_threads.
3008                          */
3009                         binder_user_error("%d:%d new transaction not allowed when there is a transaction on thread todo\n",
3010                                           proc->pid, thread->pid);
3011                         binder_inner_proc_unlock(proc);
3012                         return_error = BR_FAILED_REPLY;
3013                         return_error_param = -EPROTO;
3014                         return_error_line = __LINE__;
3015                         goto err_bad_todo_list;
3016                 }
3017 
3018                 if (!(tr->flags & TF_ONE_WAY) && thread->transaction_stack) {
3019                         struct binder_transaction *tmp;
3020 
3021                         tmp = thread->transaction_stack;
3022                         if (tmp->to_thread != thread) {
3023                                 spin_lock(&tmp->lock);
3024                                 binder_user_error("%d:%d got new transaction with bad transaction stack, transaction %d has target %d:%d\n",
3025                                         proc->pid, thread->pid, tmp->debug_id,
3026                                         tmp->to_proc ? tmp->to_proc->pid : 0,
3027                                         tmp->to_thread ?
3028                                         tmp->to_thread->pid : 0);
3029                                 spin_unlock(&tmp->lock);
3030                                 binder_inner_proc_unlock(proc);
3031                                 return_error = BR_FAILED_REPLY;
3032                                 return_error_param = -EPROTO;
3033                                 return_error_line = __LINE__;
3034                                 goto err_bad_call_stack;
3035                         }
3036                         while (tmp) {
3037                                 struct binder_thread *from;
3038 
3039                                 spin_lock(&tmp->lock);
3040                                 from = tmp->from;
3041                                 if (from && from->proc == target_proc) {
3042                                         atomic_inc(&from->tmp_ref);
3043                                         target_thread = from;
3044                                         spin_unlock(&tmp->lock);
3045                                         break;
3046                                 }
3047                                 spin_unlock(&tmp->lock);
3048                                 tmp = tmp->from_parent;
3049                         }
3050                 }
3051                 binder_inner_proc_unlock(proc);
3052         }
3053         if (target_thread)
3054                 e->to_thread = target_thread->pid;
3055         e->to_proc = target_proc->pid;
3056 
3057         /* TODO: reuse incoming transaction for reply */
3058         t = kzalloc(sizeof(*t), GFP_KERNEL);
3059         if (t == NULL) {
3060                 return_error = BR_FAILED_REPLY;
3061                 return_error_param = -ENOMEM;
3062                 return_error_line = __LINE__;
3063                 goto err_alloc_t_failed;
3064         }
3065         INIT_LIST_HEAD(&t->fd_fixups);
3066         binder_stats_created(BINDER_STAT_TRANSACTION);
3067         spin_lock_init(&t->lock);
3068 
3069         tcomplete = kzalloc(sizeof(*tcomplete), GFP_KERNEL);
3070         if (tcomplete == NULL) {
3071                 return_error = BR_FAILED_REPLY;
3072                 return_error_param = -ENOMEM;
3073                 return_error_line = __LINE__;
3074                 goto err_alloc_tcomplete_failed;
3075         }
3076         binder_stats_created(BINDER_STAT_TRANSACTION_COMPLETE);
3077 
3078         t->debug_id = t_debug_id;
3079 
3080         if (reply)
3081                 binder_debug(BINDER_DEBUG_TRANSACTION,
3082                              "%d:%d BC_REPLY %d -> %d:%d, data %016llx-%016llx size %lld-%lld-%lld\n",
3083                              proc->pid, thread->pid, t->debug_id,
3084                              target_proc->pid, target_thread->pid,
3085                              (u64)tr->data.ptr.buffer,
3086                              (u64)tr->data.ptr.offsets,
3087                              (u64)tr->data_size, (u64)tr->offsets_size,
3088                              (u64)extra_buffers_size);
3089         else
3090                 binder_debug(BINDER_DEBUG_TRANSACTION,
3091                              "%d:%d BC_TRANSACTION %d -> %d - node %d, data %016llx-%016llx size %lld-%lld-%lld\n",
3092                              proc->pid, thread->pid, t->debug_id,
3093                              target_proc->pid, target_node->debug_id,
3094                              (u64)tr->data.ptr.buffer,
3095                              (u64)tr->data.ptr.offsets,
3096                              (u64)tr->data_size, (u64)tr->offsets_size,
3097                              (u64)extra_buffers_size);
3098 
3099         if (!reply && !(tr->flags & TF_ONE_WAY))
3100                 t->from = thread;
3101         else
3102                 t->from = NULL;
3103         t->sender_euid = task_euid(proc->tsk);
3104         t->to_proc = target_proc;
3105         t->to_thread = target_thread;
3106         t->code = tr->code;
3107         t->flags = tr->flags;
3108         t->priority = task_nice(current);
3109 
3110         if (target_node && target_node->txn_security_ctx) {
3111                 u32 secid;
3112                 size_t added_size;
3113 
3114                 security_task_getsecid(proc->tsk, &secid);
3115                 ret = security_secid_to_secctx(secid, &secctx, &secctx_sz);
3116                 if (ret) {
3117                         return_error = BR_FAILED_REPLY;
3118                         return_error_param = ret;
3119                         return_error_line = __LINE__;
3120                         goto err_get_secctx_failed;
3121                 }
3122                 added_size = ALIGN(secctx_sz, sizeof(u64));
3123                 extra_buffers_size += added_size;
3124                 if (extra_buffers_size < added_size) {
3125                         /* integer overflow of extra_buffers_size */
3126                         return_error = BR_FAILED_REPLY;
3127                         return_error_param = EINVAL;
3128                         return_error_line = __LINE__;
3129                         goto err_bad_extra_size;
3130                 }
3131         }
3132 
3133         trace_binder_transaction(reply, t, target_node);
3134 
3135         t->buffer = binder_alloc_new_buf(&target_proc->alloc, tr->data_size,
3136                 tr->offsets_size, extra_buffers_size,
3137                 !reply && (t->flags & TF_ONE_WAY));
3138         if (IS_ERR(t->buffer)) {
3139                 /*
3140                  * -ESRCH indicates VMA cleared. The target is dying.
3141                  */
3142                 return_error_param = PTR_ERR(t->buffer);
3143                 return_error = return_error_param == -ESRCH ?
3144                         BR_DEAD_REPLY : BR_FAILED_REPLY;
3145                 return_error_line = __LINE__;
3146                 t->buffer = NULL;
3147                 goto err_binder_alloc_buf_failed;
3148         }
3149         if (secctx) {
3150                 int err;
3151                 size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
3152                                     ALIGN(tr->offsets_size, sizeof(void *)) +
3153                                     ALIGN(extra_buffers_size, sizeof(void *)) -
3154                                     ALIGN(secctx_sz, sizeof(u64));
3155 
3156                 t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
3157                 err = binder_alloc_copy_to_buffer(&target_proc->alloc,
3158                                                   t->buffer, buf_offset,
3159                                                   secctx, secctx_sz);
3160                 if (err) {
3161                         t->security_ctx = 0;
3162                         WARN_ON(1);
3163                 }
3164                 security_release_secctx(secctx, secctx_sz);
3165                 secctx = NULL;
3166         }
3167         t->buffer->debug_id = t->debug_id;
3168         t->buffer->transaction = t;
3169         t->buffer->target_node = target_node;
3170         trace_binder_transaction_alloc_buf(t->buffer);
3171 
3172         if (binder_alloc_copy_user_to_buffer(
3173                                 &target_proc->alloc,
3174                                 t->buffer, 0,
3175                                 (const void __user *)
3176                                         (uintptr_t)tr->data.ptr.buffer,
3177                                 tr->data_size)) {
3178                 binder_user_error("%d:%d got transaction with invalid data ptr\n",
3179                                 proc->pid, thread->pid);
3180                 return_error = BR_FAILED_REPLY;
3181                 return_error_param = -EFAULT;
3182                 return_error_line = __LINE__;
3183                 goto err_copy_data_failed;
3184         }
3185         if (binder_alloc_copy_user_to_buffer(
3186                                 &target_proc->alloc,
3187                                 t->buffer,
3188                                 ALIGN(tr->data_size, sizeof(void *)),
3189                                 (const void __user *)
3190                                         (uintptr_t)tr->data.ptr.offsets,
3191                                 tr->offsets_size)) {
3192                 binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3193                                 proc->pid, thread->pid);
3194                 return_error = BR_FAILED_REPLY;
3195                 return_error_param = -EFAULT;
3196                 return_error_line = __LINE__;
3197                 goto err_copy_data_failed;
3198         }
3199         if (!IS_ALIGNED(tr->offsets_size, sizeof(binder_size_t))) {
3200                 binder_user_error("%d:%d got transaction with invalid offsets size, %lld\n",
3201                                 proc->pid, thread->pid, (u64)tr->offsets_size);
3202                 return_error = BR_FAILED_REPLY;
3203                 return_error_param = -EINVAL;
3204                 return_error_line = __LINE__;
3205                 goto err_bad_offset;
3206         }
3207         if (!IS_ALIGNED(extra_buffers_size, sizeof(u64))) {
3208                 binder_user_error("%d:%d got transaction with unaligned buffers size, %lld\n",
3209                                   proc->pid, thread->pid,
3210                                   (u64)extra_buffers_size);
3211                 return_error = BR_FAILED_REPLY;
3212                 return_error_param = -EINVAL;
3213                 return_error_line = __LINE__;
3214                 goto err_bad_offset;
3215         }
3216         off_start_offset = ALIGN(tr->data_size, sizeof(void *));
3217         buffer_offset = off_start_offset;
3218         off_end_offset = off_start_offset + tr->offsets_size;
3219         sg_buf_offset = ALIGN(off_end_offset, sizeof(void *));
3220         sg_buf_end_offset = sg_buf_offset + extra_buffers_size -
3221                 ALIGN(secctx_sz, sizeof(u64));
3222         off_min = 0;
3223         for (buffer_offset = off_start_offset; buffer_offset < off_end_offset;
3224              buffer_offset += sizeof(binder_size_t)) {
3225                 struct binder_object_header *hdr;
3226                 size_t object_size;
3227                 struct binder_object object;
3228                 binder_size_t object_offset;
3229 
3230                 if (binder_alloc_copy_from_buffer(&target_proc->alloc,
3231                                                   &object_offset,
3232                                                   t->buffer,
3233                                                   buffer_offset,
3234                                                   sizeof(object_offset))) {
3235                         return_error = BR_FAILED_REPLY;
3236                         return_error_param = -EINVAL;
3237                         return_error_line = __LINE__;
3238                         goto err_bad_offset;
3239                 }
3240                 object_size = binder_get_object(target_proc, t->buffer,
3241                                                 object_offset, &object);
3242                 if (object_size == 0 || object_offset < off_min) {
3243                         binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n",
3244                                           proc->pid, thread->pid,
3245                                           (u64)object_offset,
3246                                           (u64)off_min,
3247                                           (u64)t->buffer->data_size);
3248                         return_error = BR_FAILED_REPLY;
3249                         return_error_param = -EINVAL;
3250                         return_error_line = __LINE__;
3251                         goto err_bad_offset;
3252                 }
3253 
3254                 hdr = &object.hdr;
3255                 off_min = object_offset + object_size;
3256                 switch (hdr->type) {
3257                 case BINDER_TYPE_BINDER:
3258                 case BINDER_TYPE_WEAK_BINDER: {
3259                         struct flat_binder_object *fp;
3260 
3261                         fp = to_flat_binder_object(hdr);
3262                         ret = binder_translate_binder(fp, t, thread);
3263 
3264                         if (ret < 0 ||
3265                             binder_alloc_copy_to_buffer(&target_proc->alloc,
3266                                                         t->buffer,
3267                                                         object_offset,
3268                                                         fp, sizeof(*fp))) {
3269                                 return_error = BR_FAILED_REPLY;
3270                                 return_error_param = ret;
3271                                 return_error_line = __LINE__;
3272                                 goto err_translate_failed;
3273                         }
3274                 } break;
3275                 case BINDER_TYPE_HANDLE:
3276                 case BINDER_TYPE_WEAK_HANDLE: {
3277                         struct flat_binder_object *fp;
3278 
3279                         fp = to_flat_binder_object(hdr);
3280                         ret = binder_translate_handle(fp, t, thread);
3281                         if (ret < 0 ||
3282                             binder_alloc_copy_to_buffer(&target_proc->alloc,
3283                                                         t->buffer,
3284                                                         object_offset,
3285                                                         fp, sizeof(*fp))) {
3286                                 return_error = BR_FAILED_REPLY;
3287                                 return_error_param = ret;
3288                                 return_error_line = __LINE__;
3289                                 goto err_translate_failed;
3290                         }
3291                 } break;
3292 
3293                 case BINDER_TYPE_FD: {
3294                         struct binder_fd_object *fp = to_binder_fd_object(hdr);
3295                         binder_size_t fd_offset = object_offset +
3296                                 (uintptr_t)&fp->fd - (uintptr_t)fp;
3297                         int ret = binder_translate_fd(fp->fd, fd_offset, t,
3298                                                       thread, in_reply_to);
3299 
3300                         fp->pad_binder = 0;
3301                         if (ret < 0 ||
3302                             binder_alloc_copy_to_buffer(&target_proc->alloc,
3303                                                         t->buffer,
3304                                                         object_offset,
3305                                                         fp, sizeof(*fp))) {
3306                                 return_error = BR_FAILED_REPLY;
3307                                 return_error_param = ret;
3308                                 return_error_line = __LINE__;
3309                                 goto err_translate_failed;
3310                         }
3311                 } break;
3312                 case BINDER_TYPE_FDA: {
3313                         struct binder_object ptr_object;
3314                         binder_size_t parent_offset;
3315                         struct binder_fd_array_object *fda =
3316                                 to_binder_fd_array_object(hdr);
3317                         size_t num_valid = (buffer_offset - off_start_offset) /
3318                                                 sizeof(binder_size_t);
3319                         struct binder_buffer_object *parent =
3320                                 binder_validate_ptr(target_proc, t->buffer,
3321                                                     &ptr_object, fda->parent,
3322                                                     off_start_offset,
3323                                                     &parent_offset,
3324                                                     num_valid);
3325                         if (!parent) {
3326                                 binder_user_error("%d:%d got transaction with invalid parent offset or type\n",
3327                                                   proc->pid, thread->pid);
3328                                 return_error = BR_FAILED_REPLY;
3329                                 return_error_param = -EINVAL;
3330                                 return_error_line = __LINE__;
3331                                 goto err_bad_parent;
3332                         }
3333                         if (!binder_validate_fixup(target_proc, t->buffer,
3334                                                    off_start_offset,
3335                                                    parent_offset,
3336                                                    fda->parent_offset,
3337                                                    last_fixup_obj_off,
3338                                                    last_fixup_min_off)) {
3339                                 binder_user_error("%d:%d got transaction with out-of-order buffer fixup\n",
3340                                                   proc->pid, thread->pid);
3341                                 return_error = BR_FAILED_REPLY;
3342                                 return_error_param = -EINVAL;
3343                                 return_error_line = __LINE__;
3344                                 goto err_bad_parent;
3345                         }
3346                         ret = binder_translate_fd_array(fda, parent, t, thread,
3347                                                         in_reply_to);
3348                         if (ret < 0) {
3349                                 return_error = BR_FAILED_REPLY;
3350                                 return_error_param = ret;
3351                                 return_error_line = __LINE__;
3352                                 goto err_translate_failed;
3353                         }
3354                         last_fixup_obj_off = parent_offset;
3355                         last_fixup_min_off =
3356                                 fda->parent_offset + sizeof(u32) * fda->num_fds;
3357                 } break;
3358                 case BINDER_TYPE_PTR: {
3359                         struct binder_buffer_object *bp =
3360                                 to_binder_buffer_object(hdr);
3361                         size_t buf_left = sg_buf_end_offset - sg_buf_offset;
3362                         size_t num_valid;
3363 
3364                         if (bp->length > buf_left) {
3365                                 binder_user_error("%d:%d got transaction with too large buffer\n",
3366                                                   proc->pid, thread->pid);
3367                                 return_error = BR_FAILED_REPLY;
3368                                 return_error_param = -EINVAL;
3369                                 return_error_line = __LINE__;
3370                                 goto err_bad_offset;
3371                         }
3372                         if (binder_alloc_copy_user_to_buffer(
3373                                                 &target_proc->alloc,
3374                                                 t->buffer,
3375                                                 sg_buf_offset,
3376                                                 (const void __user *)
3377                                                         (uintptr_t)bp->buffer,
3378                                                 bp->length)) {
3379                                 binder_user_error("%d:%d got transaction with invalid offsets ptr\n",
3380                                                   proc->pid, thread->pid);
3381                                 return_error_param = -EFAULT;
3382                                 return_error = BR_FAILED_REPLY;
3383                                 return_error_line = __LINE__;
3384                                 goto err_copy_data_failed;
3385                         }
3386                         /* Fixup buffer pointer to target proc address space */
3387                         bp->buffer = (uintptr_t)
3388                                 t->buffer->user_data + sg_buf_offset;
3389                         sg_buf_offset += ALIGN(bp->length, sizeof(u64));
3390 
3391                         num_valid = (buffer_offset - off_start_offset) /
3392                                         sizeof(binder_size_t);
3393                         ret = binder_fixup_parent(t, thread, bp,
3394                                                   off_start_offset,
3395                                                   num_valid,
3396                                                   last_fixup_obj_off,
3397                                                   last_fixup_min_off);
3398                         if (ret < 0 ||
3399                             binder_alloc_copy_to_buffer(&target_proc->alloc,
3400                                                         t->buffer,
3401                                                         object_offset,
3402                                                         bp, sizeof(*bp))) {
3403                                 return_error = BR_FAILED_REPLY;
3404                                 return_error_param = ret;
3405                                 return_error_line = __LINE__;
3406                                 goto err_translate_failed;
3407                         }
3408                         last_fixup_obj_off = object_offset;
3409                         last_fixup_min_off = 0;
3410                 } break;
3411                 default:
3412                         binder_user_error("%d:%d got transaction with invalid object type, %x\n",
3413                                 proc->pid, thread->pid, hdr->type);
3414                         return_error = BR_FAILED_REPLY;
3415                         return_error_param = -EINVAL;
3416                         return_error_line = __LINE__;
3417                         goto err_bad_object_type;
3418                 }
3419         }
3420         tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE;
3421         t->work.type = BINDER_WORK_TRANSACTION;
3422 
3423         if (reply) {
3424                 binder_enqueue_thread_work(thread, tcomplete);
3425                 binder_inner_proc_lock(target_proc);
3426                 if (target_thread->is_dead) {
3427                         binder_inner_proc_unlock(target_proc);
3428                         goto err_dead_proc_or_thread;
3429                 }
3430                 BUG_ON(t->buffer->async_transaction != 0);
3431                 binder_pop_transaction_ilocked(target_thread, in_reply_to);
3432                 binder_enqueue_thread_work_ilocked(target_thread, &t->work);
3433                 binder_inner_proc_unlock(target_proc);
3434                 wake_up_interruptible_sync(&target_thread->wait);
3435                 binder_free_transaction(in_reply_to);
3436         } else if (!(t->flags & TF_ONE_WAY)) {
3437                 BUG_ON(t->buffer->async_transaction != 0);
3438                 binder_inner_proc_lock(proc);
3439                 /*
3440                  * Defer the TRANSACTION_COMPLETE, so we don't return to
3441                  * userspace immediately; this allows the target process to
3442                  * immediately start processing this transaction, reducing
3443                  * latency. We will then return the TRANSACTION_COMPLETE when
3444                  * the target replies (or there is an error).
3445                  */
3446                 binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete);
3447                 t->need_reply = 1;
3448                 t->from_parent = thread->transaction_stack;
3449                 thread->transaction_stack = t;
3450                 binder_inner_proc_unlock(proc);
3451                 if (!binder_proc_transaction(t, target_proc, target_thread)) {
3452                         binder_inner_proc_lock(proc);
3453                         binder_pop_transaction_ilocked(thread, t);
3454                         binder_inner_proc_unlock(proc);
3455                         goto err_dead_proc_or_thread;
3456                 }
3457         } else {
3458                 BUG_ON(target_node == NULL);
3459                 BUG_ON(t->buffer->async_transaction != 1);
3460                 binder_enqueue_thread_work(thread, tcomplete);
3461                 if (!binder_proc_transaction(t, target_proc, NULL))
3462                         goto err_dead_proc_or_thread;
3463         }
3464         if (target_thread)
3465                 binder_thread_dec_tmpref(target_thread);
3466         binder_proc_dec_tmpref(target_proc);
3467         if (target_node)
3468                 binder_dec_node_tmpref(target_node);
3469         /*
3470          * write barrier to synchronize with initialization
3471          * of log entry
3472          */
3473         smp_wmb();
3474         WRITE_ONCE(e->debug_id_done, t_debug_id);
3475         return;
3476 
3477 err_dead_proc_or_thread:
3478         return_error = BR_DEAD_REPLY;
3479         return_error_line = __LINE__;
3480         binder_dequeue_work(proc, tcomplete);
3481 err_translate_failed:
3482 err_bad_object_type:
3483 err_bad_offset:
3484 err_bad_parent:
3485 err_copy_data_failed:
3486         binder_free_txn_fixups(t);
3487         trace_binder_transaction_failed_buffer_release(t->buffer);
3488         binder_transaction_buffer_release(target_proc, t->buffer,
3489                                           buffer_offset, true);
3490         if (target_node)
3491                 binder_dec_node_tmpref(target_node);
3492         target_node = NULL;
3493         t->buffer->transaction = NULL;
3494         binder_alloc_free_buf(&target_proc->alloc, t->buffer);
3495 err_binder_alloc_buf_failed:
3496 err_bad_extra_size:
3497         if (secctx)
3498                 security_release_secctx(secctx, secctx_sz);
3499 err_get_secctx_failed:
3500         kfree(tcomplete);
3501         binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
3502 err_alloc_tcomplete_failed:
3503         kfree(t);
3504         binder_stats_deleted(BINDER_STAT_TRANSACTION);
3505 err_alloc_t_failed:
3506 err_bad_todo_list:
3507 err_bad_call_stack:
3508 err_empty_call_stack:
3509 err_dead_binder:
3510 err_invalid_target_handle:
3511         if (target_thread)
3512                 binder_thread_dec_tmpref(target_thread);
3513         if (target_proc)
3514                 binder_proc_dec_tmpref(target_proc);
3515         if (target_node) {
3516                 binder_dec_node(target_node, 1, 0);
3517                 binder_dec_node_tmpref(target_node);
3518         }
3519 
3520         binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
3521                      "%d:%d transaction failed %d/%d, size %lld-%lld line %d\n",
3522                      proc->pid, thread->pid, return_error, return_error_param,
3523                      (u64)tr->data_size, (u64)tr->offsets_size,
3524                      return_error_line);
3525 
3526         {
3527                 struct binder_transaction_log_entry *fe;
3528 
3529                 e->return_error = return_error;
3530                 e->return_error_param = return_error_param;
3531                 e->return_error_line = return_error_line;
3532                 fe = binder_transaction_log_add(&binder_transaction_log_failed);
3533                 *fe = *e;
3534                 /*
3535                  * write barrier to synchronize with initialization
3536                  * of log entry
3537                  */
3538                 smp_wmb();
3539                 WRITE_ONCE(e->debug_id_done, t_debug_id);
3540                 WRITE_ONCE(fe->debug_id_done, t_debug_id);
3541         }
3542 
3543         BUG_ON(thread->return_error.cmd != BR_OK);
3544         if (in_reply_to) {
3545                 thread->return_error.cmd = BR_TRANSACTION_COMPLETE;
3546                 binder_enqueue_thread_work(thread, &thread->return_error.work);
3547                 binder_send_failed_reply(in_reply_to, return_error);
3548         } else {
3549                 thread->return_error.cmd = return_error;
3550                 binder_enqueue_thread_work(thread, &thread->return_error.work);
3551         }
3552 }
3553 
3554 /**
3555  * binder_free_buf() - free the specified buffer
3556  * @proc:       binder proc that owns buffer
3557  * @buffer:     buffer to be freed
3558  *
3559  * If buffer for an async transaction, enqueue the next async
3560  * transaction from the node.
3561  *
3562  * Cleanup buffer and free it.
3563  */
3564 static void
3565 binder_free_buf(struct binder_proc *proc, struct binder_buffer *buffer)
3566 {
3567         binder_inner_proc_lock(proc);
3568         if (buffer->transaction) {
3569                 buffer->transaction->buffer = NULL;
3570                 buffer->transaction = NULL;
3571         }
3572         binder_inner_proc_unlock(proc);
3573         if (buffer->async_transaction && buffer->target_node) {
3574                 struct binder_node *buf_node;
3575                 struct binder_work *w;
3576 
3577                 buf_node = buffer->target_node;
3578                 binder_node_inner_lock(buf_node);
3579                 BUG_ON(!buf_node->has_async_transaction);
3580                 BUG_ON(buf_node->proc != proc);
3581                 w = binder_dequeue_work_head_ilocked(
3582                                 &buf_node->async_todo);
3583                 if (!w) {
3584                         buf_node->has_async_transaction = false;
3585                 } else {
3586                         binder_enqueue_work_ilocked(
3587                                         w, &proc->todo);
3588                         binder_wakeup_proc_ilocked(proc);
3589                 }
3590                 binder_node_inner_unlock(buf_node);
3591         }
3592         trace_binder_transaction_buffer_release(buffer);
3593         binder_transaction_buffer_release(proc, buffer, 0, false);
3594         binder_alloc_free_buf(&proc->alloc, buffer);
3595 }
3596 
3597 static int binder_thread_write(struct binder_proc *proc,
3598                         struct binder_thread *thread,
3599                         binder_uintptr_t binder_buffer, size_t size,
3600                         binder_size_t *consumed)
3601 {
3602         uint32_t cmd;
3603         struct binder_context *context = proc->context;
3604         void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
3605         void __user *ptr = buffer + *consumed;
3606         void __user *end = buffer + size;
3607 
3608         while (ptr < end && thread->return_error.cmd == BR_OK) {
3609                 int ret;
3610 
3611                 if (get_user(cmd, (uint32_t __user *)ptr))
3612                         return -EFAULT;
3613                 ptr += sizeof(uint32_t);
3614                 trace_binder_command(cmd);
3615                 if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.bc)) {
3616                         atomic_inc(&binder_stats.bc[_IOC_NR(cmd)]);
3617                         atomic_inc(&proc->stats.bc[_IOC_NR(cmd)]);
3618                         atomic_inc(&thread->stats.bc[_IOC_NR(cmd)]);
3619                 }
3620                 switch (cmd) {
3621                 case BC_INCREFS:
3622                 case BC_ACQUIRE:
3623                 case BC_RELEASE:
3624                 case BC_DECREFS: {
3625                         uint32_t target;
3626                         const char *debug_string;
3627                         bool strong = cmd == BC_ACQUIRE || cmd == BC_RELEASE;
3628                         bool increment = cmd == BC_INCREFS || cmd == BC_ACQUIRE;
3629                         struct binder_ref_data rdata;
3630 
3631                         if (get_user(target, (uint32_t __user *)ptr))
3632                                 return -EFAULT;
3633 
3634                         ptr += sizeof(uint32_t);
3635                         ret = -1;
3636                         if (increment && !target) {
3637                                 struct binder_node *ctx_mgr_node;
3638                                 mutex_lock(&context->context_mgr_node_lock);
3639                                 ctx_mgr_node = context->binder_context_mgr_node;
3640                                 if (ctx_mgr_node)
3641                                         ret = binder_inc_ref_for_node(
3642                                                         proc, ctx_mgr_node,
3643                                                         strong, NULL, &rdata);
3644                                 mutex_unlock(&context->context_mgr_node_lock);
3645                         }
3646                         if (ret)
3647                                 ret = binder_update_ref_for_handle(
3648                                                 proc, target, increment, strong,
3649                                                 &rdata);
3650                         if (!ret && rdata.desc != target) {
3651                                 binder_user_error("%d:%d tried to acquire reference to desc %d, got %d instead\n",
3652                                         proc->pid, thread->pid,
3653                                         target, rdata.desc);
3654                         }
3655                         switch (cmd) {
3656                         case BC_INCREFS:
3657                                 debug_string = "IncRefs";
3658                                 break;
3659                         case BC_ACQUIRE:
3660                                 debug_string = "Acquire";
3661                                 break;
3662                         case BC_RELEASE:
3663                                 debug_string = "Release";
3664                                 break;
3665                         case BC_DECREFS:
3666                         default:
3667                                 debug_string = "DecRefs";
3668                                 break;
3669                         }
3670                         if (ret) {
3671                                 binder_user_error("%d:%d %s %d refcount change on invalid ref %d ret %d\n",
3672                                         proc->pid, thread->pid, debug_string,
3673                                         strong, target, ret);
3674                                 break;
3675                         }
3676                         binder_debug(BINDER_DEBUG_USER_REFS,
3677                                      "%d:%d %s ref %d desc %d s %d w %d\n",
3678                                      proc->pid, thread->pid, debug_string,
3679                                      rdata.debug_id, rdata.desc, rdata.strong,
3680                                      rdata.weak);
3681                         break;
3682                 }
3683                 case BC_INCREFS_DONE:
3684                 case BC_ACQUIRE_DONE: {
3685                         binder_uintptr_t node_ptr;
3686                         binder_uintptr_t cookie;
3687                         struct binder_node *node;
3688                         bool free_node;
3689 
3690                         if (get_user(node_ptr, (binder_uintptr_t __user *)ptr))
3691                                 return -EFAULT;
3692                         ptr += sizeof(binder_uintptr_t);
3693                         if (get_user(cookie, (binder_uintptr_t __user *)ptr))
3694                                 return -EFAULT;
3695                         ptr += sizeof(binder_uintptr_t);
3696                         node = binder_get_node(proc, node_ptr);
3697                         if (node == NULL) {
3698                                 binder_user_error("%d:%d %s u%016llx no match\n",
3699                                         proc->pid, thread->pid,
3700                                         cmd == BC_INCREFS_DONE ?
3701                                         "BC_INCREFS_DONE" :
3702                                         "BC_ACQUIRE_DONE",
3703                                         (u64)node_ptr);
3704                                 break;
3705                         }
3706                         if (cookie != node->cookie) {
3707                                 binder_user_error("%d:%d %s u%016llx node %d cookie mismatch %016llx != %016llx\n",
3708                                         proc->pid, thread->pid,
3709                                         cmd == BC_INCREFS_DONE ?
3710                                         "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
3711                                         (u64)node_ptr, node->debug_id,
3712                                         (u64)cookie, (u64)node->cookie);
3713                                 binder_put_node(node);
3714                                 break;
3715                         }
3716                         binder_node_inner_lock(node);
3717                         if (cmd == BC_ACQUIRE_DONE) {
3718                                 if (node->pending_strong_ref == 0) {
3719                                         binder_user_error("%d:%d BC_ACQUIRE_DONE node %d has no pending acquire request\n",
3720                                                 proc->pid, thread->pid,
3721                                                 node->debug_id);
3722                                         binder_node_inner_unlock(node);
3723                                         binder_put_node(node);
3724                                         break;
3725                                 }
3726                                 node->pending_strong_ref = 0;
3727                         } else {
3728                                 if (node->pending_weak_ref == 0) {
3729                                         binder_user_error("%d:%d BC_INCREFS_DONE node %d has no pending increfs request\n",
3730                                                 proc->pid, thread->pid,
3731                                                 node->debug_id);
3732                                         binder_node_inner_unlock(node);
3733                                         binder_put_node(node);
3734                                         break;
3735                                 }
3736                                 node->pending_weak_ref = 0;
3737                         }
3738                         free_node = binder_dec_node_nilocked(node,
3739                                         cmd == BC_ACQUIRE_DONE, 0);
3740                         WARN_ON(free_node);
3741                         binder_debug(BINDER_DEBUG_USER_REFS,
3742                                      "%d:%d %s node %d ls %d lw %d tr %d\n",
3743                                      proc->pid, thread->pid,
3744                                      cmd == BC_INCREFS_DONE ? "BC_INCREFS_DONE" : "BC_ACQUIRE_DONE",
3745                                      node->debug_id, node->local_strong_refs,
3746                                      node->local_weak_refs, node->tmp_refs);
3747                         binder_node_inner_unlock(node);
3748                         binder_put_node(node);
3749                         break;
3750                 }
3751                 case BC_ATTEMPT_ACQUIRE:
3752                         pr_err("BC_ATTEMPT_ACQUIRE not supported\n");
3753                         return -EINVAL;
3754                 case BC_ACQUIRE_RESULT:
3755                         pr_err("BC_ACQUIRE_RESULT not supported\n");
3756                         return -EINVAL;
3757 
3758                 case BC_FREE_BUFFER: {
3759                         binder_uintptr_t data_ptr;
3760                         struct binder_buffer *buffer;
3761 
3762                         if (get_user(data_ptr, (binder_uintptr_t __user *)ptr))
3763                                 return -EFAULT;
3764                         ptr += sizeof(binder_uintptr_t);
3765 
3766                         buffer = binder_alloc_prepare_to_free(&proc->alloc,
3767                                                               data_ptr);
3768                         if (IS_ERR_OR_NULL(buffer)) {
3769                                 if (PTR_ERR(buffer) == -EPERM) {
3770                                         binder_user_error(
3771                                                 "%d:%d BC_FREE_BUFFER u%016llx matched unreturned or currently freeing buffer\n",
3772                                                 proc->pid, thread->pid,
3773                                                 (u64)data_ptr);
3774                                 } else {
3775                                         binder_user_error(
3776                                                 "%d:%d BC_FREE_BUFFER u%016llx no match\n",
3777                                                 proc->pid, thread->pid,
3778                                                 (u64)data_ptr);
3779                                 }
3780                                 break;
3781                         }
3782                         binder_debug(BINDER_DEBUG_FREE_BUFFER,
3783                                      "%d:%d BC_FREE_BUFFER u%016llx found buffer %d for %s transaction\n",
3784                                      proc->pid, thread->pid, (u64)data_ptr,
3785                                      buffer->debug_id,
3786                                      buffer->transaction ? "active" : "finished");
3787                         binder_free_buf(proc, buffer);
3788                         break;
3789                 }
3790 
3791                 case BC_TRANSACTION_SG:
3792                 case BC_REPLY_SG: {
3793                         struct binder_transaction_data_sg tr;
3794 
3795                         if (copy_from_user(&tr, ptr, sizeof(tr)))
3796                                 return -EFAULT;
3797                         ptr += sizeof(tr);
3798                         binder_transaction(proc, thread, &tr.transaction_data,
3799                                            cmd == BC_REPLY_SG, tr.buffers_size);
3800                         break;
3801                 }
3802                 case BC_TRANSACTION:
3803                 case BC_REPLY: {
3804                         struct binder_transaction_data tr;
3805 
3806                         if (copy_from_user(&tr, ptr, sizeof(tr)))
3807                                 return -EFAULT;
3808                         ptr += sizeof(tr);
3809                         binder_transaction(proc, thread, &tr,
3810                                            cmd == BC_REPLY, 0);
3811                         break;
3812                 }
3813 
3814                 case BC_REGISTER_LOOPER:
3815                         binder_debug(BINDER_DEBUG_THREADS,
3816                                      "%d:%d BC_REGISTER_LOOPER\n",
3817                                      proc->pid, thread->pid);
3818                         binder_inner_proc_lock(proc);
3819                         if (thread->looper & BINDER_LOOPER_STATE_ENTERED) {
3820                                 thread->looper |= BINDER_LOOPER_STATE_INVALID;
3821                                 binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called after BC_ENTER_LOOPER\n",
3822                                         proc->pid, thread->pid);
3823                         } else if (proc->requested_threads == 0) {
3824                                 thread->looper |= BINDER_LOOPER_STATE_INVALID;
3825                                 binder_user_error("%d:%d ERROR: BC_REGISTER_LOOPER called without request\n",
3826                                         proc->pid, thread->pid);
3827                         } else {
3828                                 proc->requested_threads--;
3829                                 proc->requested_threads_started++;
3830                         }
3831                         thread->looper |= BINDER_LOOPER_STATE_REGISTERED;
3832                         binder_inner_proc_unlock(proc);
3833                         break;
3834                 case BC_ENTER_LOOPER:
3835                         binder_debug(BINDER_DEBUG_THREADS,
3836                                      "%d:%d BC_ENTER_LOOPER\n",
3837                                      proc->pid, thread->pid);
3838                         if (thread->looper & BINDER_LOOPER_STATE_REGISTERED) {
3839                                 thread->looper |= BINDER_LOOPER_STATE_INVALID;
3840                                 binder_user_error("%d:%d ERROR: BC_ENTER_LOOPER called after BC_REGISTER_LOOPER\n",
3841                                         proc->pid, thread->pid);
3842                         }
3843                         thread->looper |= BINDER_LOOPER_STATE_ENTERED;
3844                         break;
3845                 case BC_EXIT_LOOPER:
3846                         binder_debug(BINDER_DEBUG_THREADS,
3847                                      "%d:%d BC_EXIT_LOOPER\n",
3848                                      proc->pid, thread->pid);
3849                         thread->looper |= BINDER_LOOPER_STATE_EXITED;
3850                         break;
3851 
3852                 case BC_REQUEST_DEATH_NOTIFICATION:
3853                 case BC_CLEAR_DEATH_NOTIFICATION: {
3854                         uint32_t target;
3855                         binder_uintptr_t cookie;
3856                         struct binder_ref *ref;
3857                         struct binder_ref_death *death = NULL;
3858 
3859                         if (get_user(target, (uint32_t __user *)ptr))
3860                                 return -EFAULT;
3861                         ptr += sizeof(uint32_t);
3862                         if (get_user(cookie, (binder_uintptr_t __user *)ptr))
3863                                 return -EFAULT;
3864                         ptr += sizeof(binder_uintptr_t);
3865                         if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
3866                                 /*
3867                                  * Allocate memory for death notification
3868                                  * before taking lock
3869                                  */
3870                                 death = kzalloc(sizeof(*death), GFP_KERNEL);
3871                                 if (death == NULL) {
3872                                         WARN_ON(thread->return_error.cmd !=
3873                                                 BR_OK);
3874                                         thread->return_error.cmd = BR_ERROR;
3875                                         binder_enqueue_thread_work(
3876                                                 thread,
3877                                                 &thread->return_error.work);
3878                                         binder_debug(
3879                                                 BINDER_DEBUG_FAILED_TRANSACTION,
3880                                                 "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n",
3881                                                 proc->pid, thread->pid);
3882                                         break;
3883                                 }
3884                         }
3885                         binder_proc_lock(proc);
3886                         ref = binder_get_ref_olocked(proc, target, false);
3887                         if (ref == NULL) {
3888                                 binder_user_error("%d:%d %s invalid ref %d\n",
3889                                         proc->pid, thread->pid,
3890                                         cmd == BC_REQUEST_DEATH_NOTIFICATION ?
3891                                         "BC_REQUEST_DEATH_NOTIFICATION" :
3892                                         "BC_CLEAR_DEATH_NOTIFICATION",
3893                                         target);
3894                                 binder_proc_unlock(proc);
3895                                 kfree(death);
3896                                 break;
3897                         }
3898 
3899                         binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
3900                                      "%d:%d %s %016llx ref %d desc %d s %d w %d for node %d\n",
3901                                      proc->pid, thread->pid,
3902                                      cmd == BC_REQUEST_DEATH_NOTIFICATION ?
3903                                      "BC_REQUEST_DEATH_NOTIFICATION" :
3904                                      "BC_CLEAR_DEATH_NOTIFICATION",
3905                                      (u64)cookie, ref->data.debug_id,
3906                                      ref->data.desc, ref->data.strong,
3907                                      ref->data.weak, ref->node->debug_id);
3908 
3909                         binder_node_lock(ref->node);
3910                         if (cmd == BC_REQUEST_DEATH_NOTIFICATION) {
3911                                 if (ref->death) {
3912                                         binder_user_error("%d:%d BC_REQUEST_DEATH_NOTIFICATION death notification already set\n",
3913                                                 proc->pid, thread->pid);
3914                                         binder_node_unlock(ref->node);
3915                                         binder_proc_unlock(proc);
3916                                         kfree(death);
3917                                         break;
3918                                 }
3919                                 binder_stats_created(BINDER_STAT_DEATH);
3920                                 INIT_LIST_HEAD(&death->work.entry);
3921                                 death->cookie = cookie;
3922                                 ref->death = death;
3923                                 if (ref->node->proc == NULL) {
3924                                         ref->death->work.type = BINDER_WORK_DEAD_BINDER;
3925 
3926                                         binder_inner_proc_lock(proc);
3927                                         binder_enqueue_work_ilocked(
3928                                                 &ref->death->work, &proc->todo);
3929                                         binder_wakeup_proc_ilocked(proc);
3930                                         binder_inner_proc_unlock(proc);
3931                                 }
3932                         } else {
3933                                 if (ref->death == NULL) {
3934                                         binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification not active\n",
3935                                                 proc->pid, thread->pid);
3936                                         binder_node_unlock(ref->node);
3937                                         binder_proc_unlock(proc);
3938                                         break;
3939                                 }
3940                                 death = ref->death;
3941                                 if (death->cookie != cookie) {
3942                                         binder_user_error("%d:%d BC_CLEAR_DEATH_NOTIFICATION death notification cookie mismatch %016llx != %016llx\n",
3943                                                 proc->pid, thread->pid,
3944                                                 (u64)death->cookie,
3945                                                 (u64)cookie);
3946                                         binder_node_unlock(ref->node);
3947                                         binder_proc_unlock(proc);
3948                                         break;
3949                                 }
3950                                 ref->death = NULL;
3951                                 binder_inner_proc_lock(proc);
3952                                 if (list_empty(&death->work.entry)) {
3953                                         death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
3954                                         if (thread->looper &
3955                                             (BINDER_LOOPER_STATE_REGISTERED |
3956                                              BINDER_LOOPER_STATE_ENTERED))
3957                                                 binder_enqueue_thread_work_ilocked(
3958                                                                 thread,
3959                                                                 &death->work);
3960                                         else {
3961                                                 binder_enqueue_work_ilocked(
3962                                                                 &death->work,
3963                                                                 &proc->todo);
3964                                                 binder_wakeup_proc_ilocked(
3965                                                                 proc);
3966                                         }
3967                                 } else {
3968                                         BUG_ON(death->work.type != BINDER_WORK_DEAD_BINDER);
3969                                         death->work.type = BINDER_WORK_DEAD_BINDER_AND_CLEAR;
3970                                 }
3971                                 binder_inner_proc_unlock(proc);
3972                         }
3973                         binder_node_unlock(ref->node);
3974                         binder_proc_unlock(proc);
3975                 } break;
3976                 case BC_DEAD_BINDER_DONE: {
3977                         struct binder_work *w;
3978                         binder_uintptr_t cookie;
3979                         struct binder_ref_death *death = NULL;
3980 
3981                         if (get_user(cookie, (binder_uintptr_t __user *)ptr))
3982                                 return -EFAULT;
3983 
3984                         ptr += sizeof(cookie);
3985                         binder_inner_proc_lock(proc);
3986                         list_for_each_entry(w, &proc->delivered_death,
3987                                             entry) {
3988                                 struct binder_ref_death *tmp_death =
3989                                         container_of(w,
3990                                                      struct binder_ref_death,
3991                                                      work);
3992 
3993                                 if (tmp_death->cookie == cookie) {
3994                                         death = tmp_death;
3995                                         break;
3996                                 }
3997                         }
3998                         binder_debug(BINDER_DEBUG_DEAD_BINDER,
3999                                      "%d:%d BC_DEAD_BINDER_DONE %016llx found %pK\n",
4000                                      proc->pid, thread->pid, (u64)cookie,
4001                                      death);
4002                         if (death == NULL) {
4003                                 binder_user_error("%d:%d BC_DEAD_BINDER_DONE %016llx not found\n",
4004                                         proc->pid, thread->pid, (u64)cookie);
4005                                 binder_inner_proc_unlock(proc);
4006                                 break;
4007                         }
4008                         binder_dequeue_work_ilocked(&death->work);
4009                         if (death->work.type == BINDER_WORK_DEAD_BINDER_AND_CLEAR) {
4010                                 death->work.type = BINDER_WORK_CLEAR_DEATH_NOTIFICATION;
4011                                 if (thread->looper &
4012                                         (BINDER_LOOPER_STATE_REGISTERED |
4013                                          BINDER_LOOPER_STATE_ENTERED))
4014                                         binder_enqueue_thread_work_ilocked(
4015                                                 thread, &death->work);
4016                                 else {
4017                                         binder_enqueue_work_ilocked(
4018                                                         &death->work,
4019                                                         &proc->todo);
4020                                         binder_wakeup_proc_ilocked(proc);
4021                                 }
4022                         }
4023                         binder_inner_proc_unlock(proc);
4024                 } break;
4025 
4026                 default:
4027                         pr_err("%d:%d unknown command %d\n",
4028                                proc->pid, thread->pid, cmd);
4029                         return -EINVAL;
4030                 }
4031                 *consumed = ptr - buffer;
4032         }
4033         return 0;
4034 }
4035 
4036 static void binder_stat_br(struct binder_proc *proc,
4037                            struct binder_thread *thread, uint32_t cmd)
4038 {
4039         trace_binder_return(cmd);
4040         if (_IOC_NR(cmd) < ARRAY_SIZE(binder_stats.br)) {
4041                 atomic_inc(&binder_stats.br[_IOC_NR(cmd)]);
4042                 atomic_inc(&proc->stats.br[_IOC_NR(cmd)]);
4043                 atomic_inc(&thread->stats.br[_IOC_NR(cmd)]);
4044         }
4045 }
4046 
4047 static int binder_put_node_cmd(struct binder_proc *proc,
4048                                struct binder_thread *thread,
4049                                void __user **ptrp,
4050                                binder_uintptr_t node_ptr,
4051                                binder_uintptr_t node_cookie,
4052                                int node_debug_id,
4053                                uint32_t cmd, const char *cmd_name)
4054 {
4055         void __user *ptr = *ptrp;
4056 
4057         if (put_user(cmd, (uint32_t __user *)ptr))
4058                 return -EFAULT;
4059         ptr += sizeof(uint32_t);
4060 
4061         if (put_user(node_ptr, (binder_uintptr_t __user *)ptr))
4062                 return -EFAULT;
4063         ptr += sizeof(binder_uintptr_t);
4064 
4065         if (put_user(node_cookie, (binder_uintptr_t __user *)ptr))
4066                 return -EFAULT;
4067         ptr += sizeof(binder_uintptr_t);
4068 
4069         binder_stat_br(proc, thread, cmd);
4070         binder_debug(BINDER_DEBUG_USER_REFS, "%d:%d %s %d u%016llx c%016llx\n",
4071                      proc->pid, thread->pid, cmd_name, node_debug_id,
4072                      (u64)node_ptr, (u64)node_cookie);
4073 
4074         *ptrp = ptr;
4075         return 0;
4076 }
4077 
4078 static int binder_wait_for_work(struct binder_thread *thread,
4079                                 bool do_proc_work)
4080 {
4081         DEFINE_WAIT(wait);
4082         struct binder_proc *proc = thread->proc;
4083         int ret = 0;
4084 
4085         freezer_do_not_count();
4086         binder_inner_proc_lock(proc);
4087         for (;;) {
4088                 prepare_to_wait(&thread->wait, &wait, TASK_INTERRUPTIBLE);
4089                 if (binder_has_work_ilocked(thread, do_proc_work))
4090                         break;
4091                 if (do_proc_work)
4092                         list_add(&thread->waiting_thread_node,
4093                                  &proc->waiting_threads);
4094                 binder_inner_proc_unlock(proc);
4095                 schedule();
4096                 binder_inner_proc_lock(proc);
4097                 list_del_init(&thread->waiting_thread_node);
4098                 if (signal_pending(current)) {
4099                         ret = -ERESTARTSYS;
4100                         break;
4101                 }
4102         }
4103         finish_wait(&thread->wait, &wait);
4104         binder_inner_proc_unlock(proc);
4105         freezer_count();
4106 
4107         return ret;
4108 }
4109 
4110 /**
4111  * binder_apply_fd_fixups() - finish fd translation
4112  * @proc:         binder_proc associated @t->buffer
4113  * @t:  binder transaction with list of fd fixups
4114  *
4115  * Now that we are in the context of the transaction target
4116  * process, we can allocate and install fds. Process the
4117  * list of fds to translate and fixup the buffer with the
4118  * new fds.
4119  *
4120  * If we fail to allocate an fd, then free the resources by
4121  * fput'ing files that have not been processed and ksys_close'ing
4122  * any fds that have already been allocated.
4123  */
4124 static int binder_apply_fd_fixups(struct binder_proc *proc,
4125                                   struct binder_transaction *t)
4126 {
4127         struct binder_txn_fd_fixup *fixup, *tmp;
4128         int ret = 0;
4129 
4130         list_for_each_entry(fixup, &t->fd_fixups, fixup_entry) {
4131                 int fd = get_unused_fd_flags(O_CLOEXEC);
4132 
4133                 if (fd < 0) {
4134                         binder_debug(BINDER_DEBUG_TRANSACTION,
4135                                      "failed fd fixup txn %d fd %d\n",
4136                                      t->debug_id, fd);
4137                         ret = -ENOMEM;
4138                         break;
4139                 }
4140                 binder_debug(BINDER_DEBUG_TRANSACTION,
4141                              "fd fixup txn %d fd %d\n",
4142                              t->debug_id, fd);
4143                 trace_binder_transaction_fd_recv(t, fd, fixup->offset);
4144                 fd_install(fd, fixup->file);
4145                 fixup->file = NULL;
4146                 if (binder_alloc_copy_to_buffer(&proc->alloc, t->buffer,
4147                                                 fixup->offset, &fd,
4148                                                 sizeof(u32))) {
4149                         ret = -EINVAL;
4150                         break;
4151                 }
4152         }
4153         list_for_each_entry_safe(fixup, tmp, &t->fd_fixups, fixup_entry) {
4154                 if (fixup->file) {
4155                         fput(fixup->file);
4156                 } else if (ret) {
4157                         u32 fd;
4158                         int err;
4159 
4160                         err = binder_alloc_copy_from_buffer(&proc->alloc, &fd,
4161                                                             t->buffer,
4162                                                             fixup->offset,
4163                                                             sizeof(fd));
4164                         WARN_ON(err);
4165                         if (!err)
4166                                 binder_deferred_fd_close(fd);
4167                 }
4168                 list_del(&fixup->fixup_entry);
4169                 kfree(fixup);
4170         }
4171 
4172         return ret;
4173 }
4174 
4175 static int binder_thread_read(struct binder_proc *proc,
4176                               struct binder_thread *thread,
4177                               binder_uintptr_t binder_buffer, size_t size,
4178                               binder_size_t *consumed, int non_block)
4179 {
4180         void __user *buffer = (void __user *)(uintptr_t)binder_buffer;
4181         void __user *ptr = buffer + *consumed;
4182         void __user *end = buffer + size;
4183 
4184         int ret = 0;
4185         int wait_for_proc_work;
4186 
4187         if (*consumed == 0) {
4188                 if (put_user(BR_NOOP, (uint32_t __user *)ptr))
4189                         return -EFAULT;
4190                 ptr += sizeof(uint32_t);
4191         }
4192 
4193 retry:
4194         binder_inner_proc_lock(proc);
4195         wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
4196         binder_inner_proc_unlock(proc);
4197 
4198         thread->looper |= BINDER_LOOPER_STATE_WAITING;
4199 
4200         trace_binder_wait_for_work(wait_for_proc_work,
4201                                    !!thread->transaction_stack,
4202                                    !binder_worklist_empty(proc, &thread->todo));
4203         if (wait_for_proc_work) {
4204                 if (!(thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4205                                         BINDER_LOOPER_STATE_ENTERED))) {
4206                         binder_user_error("%d:%d ERROR: Thread waiting for process work before calling BC_REGISTER_LOOPER or BC_ENTER_LOOPER (state %x)\n",
4207                                 proc->pid, thread->pid, thread->looper);
4208                         wait_event_interruptible(binder_user_error_wait,
4209                                                  binder_stop_on_user_error < 2);
4210                 }
4211                 binder_set_nice(proc->default_priority);
4212         }
4213 
4214         if (non_block) {
4215                 if (!binder_has_work(thread, wait_for_proc_work))
4216                         ret = -EAGAIN;
4217         } else {
4218                 ret = binder_wait_for_work(thread, wait_for_proc_work);
4219         }
4220 
4221         thread->looper &= ~BINDER_LOOPER_STATE_WAITING;
4222 
4223         if (ret)
4224                 return ret;
4225 
4226         while (1) {
4227                 uint32_t cmd;
4228                 struct binder_transaction_data_secctx tr;
4229                 struct binder_transaction_data *trd = &tr.transaction_data;
4230                 struct binder_work *w = NULL;
4231                 struct list_head *list = NULL;
4232                 struct binder_transaction *t = NULL;
4233                 struct binder_thread *t_from;
4234                 size_t trsize = sizeof(*trd);
4235 
4236                 binder_inner_proc_lock(proc);
4237                 if (!binder_worklist_empty_ilocked(&thread->todo))
4238                         list = &thread->todo;
4239                 else if (!binder_worklist_empty_ilocked(&proc->todo) &&
4240                            wait_for_proc_work)
4241                         list = &proc->todo;
4242                 else {
4243                         binder_inner_proc_unlock(proc);
4244 
4245                         /* no data added */
4246                         if (ptr - buffer == 4 && !thread->looper_need_return)
4247                                 goto retry;
4248                         break;
4249                 }
4250 
4251                 if (end - ptr < sizeof(tr) + 4) {
4252                         binder_inner_proc_unlock(proc);
4253                         break;
4254                 }
4255                 w = binder_dequeue_work_head_ilocked(list);
4256                 if (binder_worklist_empty_ilocked(&thread->todo))
4257                         thread->process_todo = false;
4258 
4259                 switch (w->type) {
4260                 case BINDER_WORK_TRANSACTION: {
4261                         binder_inner_proc_unlock(proc);
4262                         t = container_of(w, struct binder_transaction, work);
4263                 } break;
4264                 case BINDER_WORK_RETURN_ERROR: {
4265                         struct binder_error *e = container_of(
4266                                         w, struct binder_error, work);
4267 
4268                         WARN_ON(e->cmd == BR_OK);
4269                         binder_inner_proc_unlock(proc);
4270                         if (put_user(e->cmd, (uint32_t __user *)ptr))
4271                                 return -EFAULT;
4272                         cmd = e->cmd;
4273                         e->cmd = BR_OK;
4274                         ptr += sizeof(uint32_t);
4275 
4276                         binder_stat_br(proc, thread, cmd);
4277                 } break;
4278                 case BINDER_WORK_TRANSACTION_COMPLETE: {
4279                         binder_inner_proc_unlock(proc);
4280                         cmd = BR_TRANSACTION_COMPLETE;
4281                         kfree(w);
4282                         binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4283                         if (put_user(cmd, (uint32_t __user *)ptr))
4284                                 return -EFAULT;
4285                         ptr += sizeof(uint32_t);
4286 
4287                         binder_stat_br(proc, thread, cmd);
4288                         binder_debug(BINDER_DEBUG_TRANSACTION_COMPLETE,
4289                                      "%d:%d BR_TRANSACTION_COMPLETE\n",
4290                                      proc->pid, thread->pid);
4291                 } break;
4292                 case BINDER_WORK_NODE: {
4293                         struct binder_node *node = container_of(w, struct binder_node, work);
4294                         int strong, weak;
4295                         binder_uintptr_t node_ptr = node->ptr;
4296                         binder_uintptr_t node_cookie = node->cookie;
4297                         int node_debug_id = node->debug_id;
4298                         int has_weak_ref;
4299                         int has_strong_ref;
4300                         void __user *orig_ptr = ptr;
4301 
4302                         BUG_ON(proc != node->proc);
4303                         strong = node->internal_strong_refs ||
4304                                         node->local_strong_refs;
4305                         weak = !hlist_empty(&node->refs) ||
4306                                         node->local_weak_refs ||
4307                                         node->tmp_refs || strong;
4308                         has_strong_ref = node->has_strong_ref;
4309                         has_weak_ref = node->has_weak_ref;
4310 
4311                         if (weak && !has_weak_ref) {
4312                                 node->has_weak_ref = 1;
4313                                 node->pending_weak_ref = 1;
4314                                 node->local_weak_refs++;
4315                         }
4316                         if (strong && !has_strong_ref) {
4317                                 node->has_strong_ref = 1;
4318                                 node->pending_strong_ref = 1;
4319                                 node->local_strong_refs++;
4320                         }
4321                         if (!strong && has_strong_ref)
4322                                 node->has_strong_ref = 0;
4323                         if (!weak && has_weak_ref)
4324                                 node->has_weak_ref = 0;
4325                         if (!weak && !strong) {
4326                                 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4327                                              "%d:%d node %d u%016llx c%016llx deleted\n",
4328                                              proc->pid, thread->pid,
4329                                              node_debug_id,
4330                                              (u64)node_ptr,
4331                                              (u64)node_cookie);
4332                                 rb_erase(&node->rb_node, &proc->nodes);
4333                                 binder_inner_proc_unlock(proc);
4334                                 binder_node_lock(node);
4335                                 /*
4336                                  * Acquire the node lock before freeing the
4337                                  * node to serialize with other threads that
4338                                  * may have been holding the node lock while
4339                                  * decrementing this node (avoids race where
4340                                  * this thread frees while the other thread
4341                                  * is unlocking the node after the final
4342                                  * decrement)
4343                                  */
4344                                 binder_node_unlock(node);
4345                                 binder_free_node(node);
4346                         } else
4347                                 binder_inner_proc_unlock(proc);
4348 
4349                         if (weak && !has_weak_ref)
4350                                 ret = binder_put_node_cmd(
4351                                                 proc, thread, &ptr, node_ptr,
4352                                                 node_cookie, node_debug_id,
4353                                                 BR_INCREFS, "BR_INCREFS");
4354                         if (!ret && strong && !has_strong_ref)
4355                                 ret = binder_put_node_cmd(
4356                                                 proc, thread, &ptr, node_ptr,
4357                                                 node_cookie, node_debug_id,
4358                                                 BR_ACQUIRE, "BR_ACQUIRE");
4359                         if (!ret && !strong && has_strong_ref)
4360                                 ret = binder_put_node_cmd(
4361                                                 proc, thread, &ptr, node_ptr,
4362                                                 node_cookie, node_debug_id,
4363                                                 BR_RELEASE, "BR_RELEASE");
4364                         if (!ret && !weak && has_weak_ref)
4365                                 ret = binder_put_node_cmd(
4366                                                 proc, thread, &ptr, node_ptr,
4367                                                 node_cookie, node_debug_id,
4368                                                 BR_DECREFS, "BR_DECREFS");
4369                         if (orig_ptr == ptr)
4370                                 binder_debug(BINDER_DEBUG_INTERNAL_REFS,
4371                                              "%d:%d node %d u%016llx c%016llx state unchanged\n",
4372                                              proc->pid, thread->pid,
4373                                              node_debug_id,
4374                                              (u64)node_ptr,
4375                                              (u64)node_cookie);
4376                         if (ret)
4377                                 return ret;
4378                 } break;
4379                 case BINDER_WORK_DEAD_BINDER:
4380                 case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
4381                 case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
4382                         struct binder_ref_death *death;
4383                         uint32_t cmd;
4384                         binder_uintptr_t cookie;
4385 
4386                         death = container_of(w, struct binder_ref_death, work);
4387                         if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION)
4388                                 cmd = BR_CLEAR_DEATH_NOTIFICATION_DONE;
4389                         else
4390                                 cmd = BR_DEAD_BINDER;
4391                         cookie = death->cookie;
4392 
4393                         binder_debug(BINDER_DEBUG_DEATH_NOTIFICATION,
4394                                      "%d:%d %s %016llx\n",
4395                                       proc->pid, thread->pid,
4396                                       cmd == BR_DEAD_BINDER ?
4397                                       "BR_DEAD_BINDER" :
4398                                       "BR_CLEAR_DEATH_NOTIFICATION_DONE",
4399                                       (u64)cookie);
4400                         if (w->type == BINDER_WORK_CLEAR_DEATH_NOTIFICATION) {
4401                                 binder_inner_proc_unlock(proc);
4402                                 kfree(death);
4403                                 binder_stats_deleted(BINDER_STAT_DEATH);
4404                         } else {
4405                                 binder_enqueue_work_ilocked(
4406                                                 w, &proc->delivered_death);
4407                                 binder_inner_proc_unlock(proc);
4408                         }
4409                         if (put_user(cmd, (uint32_t __user *)ptr))
4410                                 return -EFAULT;
4411                         ptr += sizeof(uint32_t);
4412                         if (put_user(cookie,
4413                                      (binder_uintptr_t __user *)ptr))
4414                                 return -EFAULT;
4415                         ptr += sizeof(binder_uintptr_t);
4416                         binder_stat_br(proc, thread, cmd);
4417                         if (cmd == BR_DEAD_BINDER)
4418                                 goto done; /* DEAD_BINDER notifications can cause transactions */
4419                 } break;
4420                 default:
4421                         binder_inner_proc_unlock(proc);
4422                         pr_err("%d:%d: bad work type %d\n",
4423                                proc->pid, thread->pid, w->type);
4424                         break;
4425                 }
4426 
4427                 if (!t)
4428                         continue;
4429 
4430                 BUG_ON(t->buffer == NULL);
4431                 if (t->buffer->target_node) {
4432                         struct binder_node *target_node = t->buffer->target_node;
4433 
4434                         trd->target.ptr = target_node->ptr;
4435                         trd->cookie =  target_node->cookie;
4436                         t->saved_priority = task_nice(current);
4437                         if (t->priority < target_node->min_priority &&
4438                             !(t->flags & TF_ONE_WAY))
4439                                 binder_set_nice(t->priority);
4440                         else if (!(t->flags & TF_ONE_WAY) ||
4441                                  t->saved_priority > target_node->min_priority)
4442                                 binder_set_nice(target_node->min_priority);
4443                         cmd = BR_TRANSACTION;
4444                 } else {
4445                         trd->target.ptr = 0;
4446                         trd->cookie = 0;
4447                         cmd = BR_REPLY;
4448                 }
4449                 trd->code = t->code;
4450                 trd->flags = t->flags;
4451                 trd->sender_euid = from_kuid(current_user_ns(), t->sender_euid);
4452 
4453                 t_from = binder_get_txn_from(t);
4454                 if (t_from) {
4455                         struct task_struct *sender = t_from->proc->tsk;
4456 
4457                         trd->sender_pid =
4458                                 task_tgid_nr_ns(sender,
4459                                                 task_active_pid_ns(current));
4460                 } else {
4461                         trd->sender_pid = 0;
4462                 }
4463 
4464                 ret = binder_apply_fd_fixups(proc, t);
4465                 if (ret) {
4466                         struct binder_buffer *buffer = t->buffer;
4467                         bool oneway = !!(t->flags & TF_ONE_WAY);
4468                         int tid = t->debug_id;
4469 
4470                         if (t_from)
4471                                 binder_thread_dec_tmpref(t_from);
4472                         buffer->transaction = NULL;
4473                         binder_cleanup_transaction(t, "fd fixups failed",
4474                                                    BR_FAILED_REPLY);
4475                         binder_free_buf(proc, buffer);
4476                         binder_debug(BINDER_DEBUG_FAILED_TRANSACTION,
4477                                      "%d:%d %stransaction %d fd fixups failed %d/%d, line %d\n",
4478                                      proc->pid, thread->pid,
4479                                      oneway ? "async " :
4480                                         (cmd == BR_REPLY ? "reply " : ""),
4481                                      tid, BR_FAILED_REPLY, ret, __LINE__);
4482                         if (cmd == BR_REPLY) {
4483                                 cmd = BR_FAILED_REPLY;
4484                                 if (put_user(cmd, (uint32_t __user *)ptr))
4485                                         return -EFAULT;
4486                                 ptr += sizeof(uint32_t);
4487                                 binder_stat_br(proc, thread, cmd);
4488                                 break;
4489                         }
4490                         continue;
4491                 }
4492                 trd->data_size = t->buffer->data_size;
4493                 trd->offsets_size = t->buffer->offsets_size;
4494                 trd->data.ptr.buffer = (uintptr_t)t->buffer->user_data;
4495                 trd->data.ptr.offsets = trd->data.ptr.buffer +
4496                                         ALIGN(t->buffer->data_size,
4497                                             sizeof(void *));
4498 
4499                 tr.secctx = t->security_ctx;
4500                 if (t->security_ctx) {
4501                         cmd = BR_TRANSACTION_SEC_CTX;
4502                         trsize = sizeof(tr);
4503                 }
4504                 if (put_user(cmd, (uint32_t __user *)ptr)) {
4505                         if (t_from)
4506                                 binder_thread_dec_tmpref(t_from);
4507 
4508                         binder_cleanup_transaction(t, "put_user failed",
4509                                                    BR_FAILED_REPLY);
4510 
4511                         return -EFAULT;
4512                 }
4513                 ptr += sizeof(uint32_t);
4514                 if (copy_to_user(ptr, &tr, trsize)) {
4515                         if (t_from)
4516                                 binder_thread_dec_tmpref(t_from);
4517 
4518                         binder_cleanup_transaction(t, "copy_to_user failed",
4519                                                    BR_FAILED_REPLY);
4520 
4521                         return -EFAULT;
4522                 }
4523                 ptr += trsize;
4524 
4525                 trace_binder_transaction_received(t);
4526                 binder_stat_br(proc, thread, cmd);
4527                 binder_debug(BINDER_DEBUG_TRANSACTION,
4528                              "%d:%d %s %d %d:%d, cmd %d size %zd-%zd ptr %016llx-%016llx\n",
4529                              proc->pid, thread->pid,
4530                              (cmd == BR_TRANSACTION) ? "BR_TRANSACTION" :
4531                                 (cmd == BR_TRANSACTION_SEC_CTX) ?
4532                                      "BR_TRANSACTION_SEC_CTX" : "BR_REPLY",
4533                              t->debug_id, t_from ? t_from->proc->pid : 0,
4534                              t_from ? t_from->pid : 0, cmd,
4535                              t->buffer->data_size, t->buffer->offsets_size,
4536                              (u64)trd->data.ptr.buffer,
4537                              (u64)trd->data.ptr.offsets);
4538 
4539                 if (t_from)
4540                         binder_thread_dec_tmpref(t_from);
4541                 t->buffer->allow_user_free = 1;
4542                 if (cmd != BR_REPLY && !(t->flags & TF_ONE_WAY)) {
4543                         binder_inner_proc_lock(thread->proc);
4544                         t->to_parent = thread->transaction_stack;
4545                         t->to_thread = thread;
4546                         thread->transaction_stack = t;
4547                         binder_inner_proc_unlock(thread->proc);
4548                 } else {
4549                         binder_free_transaction(t);
4550                 }
4551                 break;
4552         }
4553 
4554 done:
4555 
4556         *consumed = ptr - buffer;
4557         binder_inner_proc_lock(proc);
4558         if (proc->requested_threads == 0 &&
4559             list_empty(&thread->proc->waiting_threads) &&
4560             proc->requested_threads_started < proc->max_threads &&
4561             (thread->looper & (BINDER_LOOPER_STATE_REGISTERED |
4562              BINDER_LOOPER_STATE_ENTERED)) /* the user-space code fails to */
4563              /*spawn a new thread if we leave this out */) {
4564                 proc->requested_threads++;
4565                 binder_inner_proc_unlock(proc);
4566                 binder_debug(BINDER_DEBUG_THREADS,
4567                              "%d:%d BR_SPAWN_LOOPER\n",
4568                              proc->pid, thread->pid);
4569                 if (put_user(BR_SPAWN_LOOPER, (uint32_t __user *)buffer))
4570                         return -EFAULT;
4571                 binder_stat_br(proc, thread, BR_SPAWN_LOOPER);
4572         } else
4573                 binder_inner_proc_unlock(proc);
4574         return 0;
4575 }
4576 
4577 static void binder_release_work(struct binder_proc *proc,
4578                                 struct list_head *list)
4579 {
4580         struct binder_work *w;
4581 
4582         while (1) {
4583                 w = binder_dequeue_work_head(proc, list);
4584                 if (!w)
4585                         return;
4586 
4587                 switch (w->type) {
4588                 case BINDER_WORK_TRANSACTION: {
4589                         struct binder_transaction *t;
4590 
4591                         t = container_of(w, struct binder_transaction, work);
4592 
4593                         binder_cleanup_transaction(t, "process died.",
4594                                                    BR_DEAD_REPLY);
4595                 } break;
4596                 case BINDER_WORK_RETURN_ERROR: {
4597                         struct binder_error *e = container_of(
4598                                         w, struct binder_error, work);
4599 
4600                         binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4601                                 "undelivered TRANSACTION_ERROR: %u\n",
4602                                 e->cmd);
4603                 } break;
4604                 case BINDER_WORK_TRANSACTION_COMPLETE: {
4605                         binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4606                                 "undelivered TRANSACTION_COMPLETE\n");
4607                         kfree(w);
4608                         binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
4609                 } break;
4610                 case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
4611                 case BINDER_WORK_CLEAR_DEATH_NOTIFICATION: {
4612                         struct binder_ref_death *death;
4613 
4614                         death = container_of(w, struct binder_ref_death, work);
4615                         binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4616                                 "undelivered death notification, %016llx\n",
4617                                 (u64)death->cookie);
4618                         kfree(death);
4619                         binder_stats_deleted(BINDER_STAT_DEATH);
4620                 } break;
4621                 default:
4622                         pr_err("unexpected work type, %d, not freed\n",
4623                                w->type);
4624                         break;
4625                 }
4626         }
4627 
4628 }
4629 
4630 static struct binder_thread *binder_get_thread_ilocked(
4631                 struct binder_proc *proc, struct binder_thread *new_thread)
4632 {
4633         struct binder_thread *thread = NULL;
4634         struct rb_node *parent = NULL;
4635         struct rb_node **p = &proc->threads.rb_node;
4636 
4637         while (*p) {
4638                 parent = *p;
4639                 thread = rb_entry(parent, struct binder_thread, rb_node);
4640 
4641                 if (current->pid < thread->pid)
4642                         p = &(*p)->rb_left;
4643                 else if (current->pid > thread->pid)
4644                         p = &(*p)->rb_right;
4645                 else
4646                         return thread;
4647         }
4648         if (!new_thread)
4649                 return NULL;
4650         thread = new_thread;
4651         binder_stats_created(BINDER_STAT_THREAD);
4652         thread->proc = proc;
4653         thread->pid = current->pid;
4654         atomic_set(&thread->tmp_ref, 0);
4655         init_waitqueue_head(&thread->wait);
4656         INIT_LIST_HEAD(&thread->todo);
4657         rb_link_node(&thread->rb_node, parent, p);
4658         rb_insert_color(&thread->rb_node, &proc->threads);
4659         thread->looper_need_return = true;
4660         thread->return_error.work.type = BINDER_WORK_RETURN_ERROR;
4661         thread->return_error.cmd = BR_OK;
4662         thread->reply_error.work.type = BINDER_WORK_RETURN_ERROR;
4663         thread->reply_error.cmd = BR_OK;
4664         INIT_LIST_HEAD(&new_thread->waiting_thread_node);
4665         return thread;
4666 }
4667 
4668 static struct binder_thread *binder_get_thread(struct binder_proc *proc)
4669 {
4670         struct binder_thread *thread;
4671         struct binder_thread *new_thread;
4672 
4673         binder_inner_proc_lock(proc);
4674         thread = binder_get_thread_ilocked(proc, NULL);
4675         binder_inner_proc_unlock(proc);
4676         if (!thread) {
4677                 new_thread = kzalloc(sizeof(*thread), GFP_KERNEL);
4678                 if (new_thread == NULL)
4679                         return NULL;
4680                 binder_inner_proc_lock(proc);
4681                 thread = binder_get_thread_ilocked(proc, new_thread);
4682                 binder_inner_proc_unlock(proc);
4683                 if (thread != new_thread)
4684                         kfree(new_thread);
4685         }
4686         return thread;
4687 }
4688 
4689 static void binder_free_proc(struct binder_proc *proc)
4690 {
4691         BUG_ON(!list_empty(&proc->todo));
4692         BUG_ON(!list_empty(&proc->delivered_death));
4693         binder_alloc_deferred_release(&proc->alloc);
4694         put_task_struct(proc->tsk);
4695         binder_stats_deleted(BINDER_STAT_PROC);
4696         kfree(proc);
4697 }
4698 
4699 static void binder_free_thread(struct binder_thread *thread)
4700 {
4701         BUG_ON(!list_empty(&thread->todo));
4702         binder_stats_deleted(BINDER_STAT_THREAD);
4703         binder_proc_dec_tmpref(thread->proc);
4704         kfree(thread);
4705 }
4706 
4707 static int binder_thread_release(struct binder_proc *proc,
4708                                  struct binder_thread *thread)
4709 {
4710         struct binder_transaction *t;
4711         struct binder_transaction *send_reply = NULL;
4712         int active_transactions = 0;
4713         struct binder_transaction *last_t = NULL;
4714 
4715         binder_inner_proc_lock(thread->proc);
4716         /*
4717          * take a ref on the proc so it survives
4718          * after we remove this thread from proc->threads.
4719          * The corresponding dec is when we actually
4720          * free the thread in binder_free_thread()
4721          */
4722         proc->tmp_ref++;
4723         /*
4724          * take a ref on this thread to ensure it
4725          * survives while we are releasing it
4726          */
4727         atomic_inc(&thread->tmp_ref);
4728         rb_erase(&thread->rb_node, &proc->threads);
4729         t = thread->transaction_stack;
4730         if (t) {
4731                 spin_lock(&t->lock);
4732                 if (t->to_thread == thread)
4733                         send_reply = t;
4734         } else {
4735                 __acquire(&t->lock);
4736         }
4737         thread->is_dead = true;
4738 
4739         while (t) {
4740                 last_t = t;
4741                 active_transactions++;
4742                 binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
4743                              "release %d:%d transaction %d %s, still active\n",
4744                               proc->pid, thread->pid,
4745                              t->debug_id,
4746                              (t->to_thread == thread) ? "in" : "out");
4747 
4748                 if (t->to_thread == thread) {
4749                         t->to_proc = NULL;
4750                         t->to_thread = NULL;
4751                         if (t->buffer) {
4752                                 t->buffer->transaction = NULL;
4753                                 t->buffer = NULL;
4754                         }
4755                         t = t->to_parent;
4756                 } else if (t->from == thread) {
4757                         t->from = NULL;
4758                         t = t->from_parent;
4759                 } else
4760                         BUG();
4761                 spin_unlock(&last_t->lock);
4762                 if (t)
4763                         spin_lock(&t->lock);
4764                 else
4765                         __acquire(&t->lock);
4766         }
4767         /* annotation for sparse, lock not acquired in last iteration above */
4768         __release(&t->lock);
4769 
4770         /*
4771          * If this thread used poll, make sure we remove the waitqueue
4772          * from any epoll data structures holding it with POLLFREE.
4773          * waitqueue_active() is safe to use here because we're holding
4774          * the inner lock.
4775          */
4776         if ((thread->looper & BINDER_LOOPER_STATE_POLL) &&
4777             waitqueue_active(&thread->wait)) {
4778                 wake_up_poll(&thread->wait, EPOLLHUP | POLLFREE);
4779         }
4780 
4781         binder_inner_proc_unlock(thread->proc);
4782 
4783         /*
4784          * This is needed to avoid races between wake_up_poll() above and
4785          * and ep_remove_waitqueue() called for other reasons (eg the epoll file
4786          * descriptor being closed); ep_remove_waitqueue() holds an RCU read
4787          * lock, so we can be sure it's done after calling synchronize_rcu().
4788          */
4789         if (thread->looper & BINDER_LOOPER_STATE_POLL)
4790                 synchronize_rcu();
4791 
4792         if (send_reply)
4793                 binder_send_failed_reply(send_reply, BR_DEAD_REPLY);
4794         binder_release_work(proc, &thread->todo);
4795         binder_thread_dec_tmpref(thread);
4796         return active_transactions;
4797 }
4798 
4799 static __poll_t binder_poll(struct file *filp,
4800                                 struct poll_table_struct *wait)
4801 {
4802         struct binder_proc *proc = filp->private_data;
4803         struct binder_thread *thread = NULL;
4804         bool wait_for_proc_work;
4805 
4806         thread = binder_get_thread(proc);
4807         if (!thread)
4808                 return POLLERR;
4809 
4810         binder_inner_proc_lock(thread->proc);
4811         thread->looper |= BINDER_LOOPER_STATE_POLL;
4812         wait_for_proc_work = binder_available_for_proc_work_ilocked(thread);
4813 
4814         binder_inner_proc_unlock(thread->proc);
4815 
4816         poll_wait(filp, &thread->wait, wait);
4817 
4818         if (binder_has_work(thread, wait_for_proc_work))
4819                 return EPOLLIN;
4820 
4821         return 0;
4822 }
4823 
4824 static int binder_ioctl_write_read(struct file *filp,
4825                                 unsigned int cmd, unsigned long arg,
4826                                 struct binder_thread *thread)
4827 {
4828         int ret = 0;
4829         struct binder_proc *proc = filp->private_data;
4830         unsigned int size = _IOC_SIZE(cmd);
4831         void __user *ubuf = (void __user *)arg;
4832         struct binder_write_read bwr;
4833 
4834         if (size != sizeof(struct binder_write_read)) {
4835                 ret = -EINVAL;
4836                 goto out;
4837         }
4838         if (copy_from_user(&bwr, ubuf, sizeof(bwr))) {
4839                 ret = -EFAULT;
4840                 goto out;
4841         }
4842         binder_debug(BINDER_DEBUG_READ_WRITE,
4843                      "%d:%d write %lld at %016llx, read %lld at %016llx\n",
4844                      proc->pid, thread->pid,
4845                      (u64)bwr.write_size, (u64)bwr.write_buffer,
4846                      (u64)bwr.read_size, (u64)bwr.read_buffer);
4847 
4848         if (bwr.write_size > 0) {
4849                 ret = binder_thread_write(proc, thread,
4850                                           bwr.write_buffer,
4851                                           bwr.write_size,
4852                                           &bwr.write_consumed);
4853                 trace_binder_write_done(ret);
4854                 if (ret < 0) {
4855                         bwr.read_consumed = 0;
4856                         if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
4857                                 ret = -EFAULT;
4858                         goto out;
4859                 }
4860         }
4861         if (bwr.read_size > 0) {
4862                 ret = binder_thread_read(proc, thread, bwr.read_buffer,
4863                                          bwr.read_size,
4864                                          &bwr.read_consumed,
4865                                          filp->f_flags & O_NONBLOCK);
4866                 trace_binder_read_done(ret);
4867                 binder_inner_proc_lock(proc);
4868                 if (!binder_worklist_empty_ilocked(&proc->todo))
4869                         binder_wakeup_proc_ilocked(proc);
4870                 binder_inner_proc_unlock(proc);
4871                 if (ret < 0) {
4872                         if (copy_to_user(ubuf, &bwr, sizeof(bwr)))
4873                                 ret = -EFAULT;
4874                         goto out;
4875                 }
4876         }
4877         binder_debug(BINDER_DEBUG_READ_WRITE,
4878                      "%d:%d wrote %lld of %lld, read return %lld of %lld\n",
4879                      proc->pid, thread->pid,
4880                      (u64)bwr.write_consumed, (u64)bwr.write_size,
4881                      (u64)bwr.read_consumed, (u64)bwr.read_size);
4882         if (copy_to_user(ubuf, &bwr, sizeof(bwr))) {
4883                 ret = -EFAULT;
4884                 goto out;
4885         }
4886 out:
4887         return ret;
4888 }
4889 
4890 static int binder_ioctl_set_ctx_mgr(struct file *filp,
4891                                     struct flat_binder_object *fbo)
4892 {
4893         int ret = 0;
4894         struct binder_proc *proc = filp->private_data;
4895         struct binder_context *context = proc->context;
4896         struct binder_node *new_node;
4897         kuid_t curr_euid = current_euid();
4898 
4899         mutex_lock(&context->context_mgr_node_lock);
4900         if (context->binder_context_mgr_node) {
4901                 pr_err("BINDER_SET_CONTEXT_MGR already set\n");
4902                 ret = -EBUSY;
4903                 goto out;
4904         }
4905         ret = security_binder_set_context_mgr(proc->tsk);
4906         if (ret < 0)
4907                 goto out;
4908         if (uid_valid(context->binder_context_mgr_uid)) {
4909                 if (!uid_eq(context->binder_context_mgr_uid, curr_euid)) {
4910                         pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
4911                                from_kuid(&init_user_ns, curr_euid),
4912                                from_kuid(&init_user_ns,
4913                                          context->binder_context_mgr_uid));
4914                         ret = -EPERM;
4915                         goto out;
4916                 }
4917         } else {
4918                 context->binder_context_mgr_uid = curr_euid;
4919         }
4920         new_node = binder_new_node(proc, fbo);
4921         if (!new_node) {
4922                 ret = -ENOMEM;
4923                 goto out;
4924         }
4925         binder_node_lock(new_node);
4926         new_node->local_weak_refs++;
4927         new_node->local_strong_refs++;
4928         new_node->has_strong_ref = 1;
4929         new_node->has_weak_ref = 1;
4930         context->binder_context_mgr_node = new_node;
4931         binder_node_unlock(new_node);
4932         binder_put_node(new_node);
4933 out:
4934         mutex_unlock(&context->context_mgr_node_lock);
4935         return ret;
4936 }
4937 
4938 static int binder_ioctl_get_node_info_for_ref(struct binder_proc *proc,
4939                 struct binder_node_info_for_ref *info)
4940 {
4941         struct binder_node *node;
4942         struct binder_context *context = proc->context;
4943         __u32 handle = info->handle;
4944 
4945         if (info->strong_count || info->weak_count || info->reserved1 ||
4946             info->reserved2 || info->reserved3) {
4947                 binder_user_error("%d BINDER_GET_NODE_INFO_FOR_REF: only handle may be non-zero.",
4948                                   proc->pid);
4949                 return -EINVAL;
4950         }
4951 
4952         /* This ioctl may only be used by the context manager */
4953         mutex_lock(&context->context_mgr_node_lock);
4954         if (!context->binder_context_mgr_node ||
4955                 context->binder_context_mgr_node->proc != proc) {
4956                 mutex_unlock(&context->context_mgr_node_lock);
4957                 return -EPERM;
4958         }
4959         mutex_unlock(&context->context_mgr_node_lock);
4960 
4961         node = binder_get_node_from_ref(proc, handle, true, NULL);
4962         if (!node)
4963                 return -EINVAL;
4964 
4965         info->strong_count = node->local_strong_refs +
4966                 node->internal_strong_refs;
4967         info->weak_count = node->local_weak_refs;
4968 
4969         binder_put_node(node);
4970 
4971         return 0;
4972 }
4973 
4974 static int binder_ioctl_get_node_debug_info(struct binder_proc *proc,
4975                                 struct binder_node_debug_info *info)
4976 {
4977         struct rb_node *n;
4978         binder_uintptr_t ptr = info->ptr;
4979 
4980         memset(info, 0, sizeof(*info));
4981 
4982         binder_inner_proc_lock(proc);
4983         for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
4984                 struct binder_node *node = rb_entry(n, struct binder_node,
4985                                                     rb_node);
4986                 if (node->ptr > ptr) {
4987                         info->ptr = node->ptr;
4988                         info->cookie = node->cookie;
4989                         info->has_strong_ref = node->has_strong_ref;
4990                         info->has_weak_ref = node->has_weak_ref;
4991                         break;
4992                 }
4993         }
4994         binder_inner_proc_unlock(proc);
4995 
4996         return 0;
4997 }
4998 
4999 static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
5000 {
5001         int ret;
5002         struct binder_proc *proc = filp->private_data;
5003         struct binder_thread *thread;
5004         unsigned int size = _IOC_SIZE(cmd);
5005         void __user *ubuf = (void __user *)arg;
5006 
5007         /*pr_info("binder_ioctl: %d:%d %x %lx\n",
5008                         proc->pid, current->pid, cmd, arg);*/
5009 
5010         binder_selftest_alloc(&proc->alloc);
5011 
5012         trace_binder_ioctl(cmd, arg);
5013 
5014         ret = wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5015         if (ret)
5016                 goto err_unlocked;
5017 
5018         thread = binder_get_thread(proc);
5019         if (thread == NULL) {
5020                 ret = -ENOMEM;
5021                 goto err;
5022         }
5023 
5024         switch (cmd) {
5025         case BINDER_WRITE_READ:
5026                 ret = binder_ioctl_write_read(filp, cmd, arg, thread);
5027                 if (ret)
5028                         goto err;
5029                 break;
5030         case BINDER_SET_MAX_THREADS: {
5031                 int max_threads;
5032 
5033                 if (copy_from_user(&max_threads, ubuf,
5034                                    sizeof(max_threads))) {
5035                         ret = -EINVAL;
5036                         goto err;
5037                 }
5038                 binder_inner_proc_lock(proc);
5039                 proc->max_threads = max_threads;
5040                 binder_inner_proc_unlock(proc);
5041                 break;
5042         }
5043         case BINDER_SET_CONTEXT_MGR_EXT: {
5044                 struct flat_binder_object fbo;
5045 
5046                 if (copy_from_user(&fbo, ubuf, sizeof(fbo))) {
5047                         ret = -EINVAL;
5048                         goto err;
5049                 }
5050                 ret = binder_ioctl_set_ctx_mgr(filp, &fbo);
5051                 if (ret)
5052                         goto err;
5053                 break;
5054         }
5055         case BINDER_SET_CONTEXT_MGR:
5056                 ret = binder_ioctl_set_ctx_mgr(filp, NULL);
5057                 if (ret)
5058                         goto err;
5059                 break;
5060         case BINDER_THREAD_EXIT:
5061                 binder_debug(BINDER_DEBUG_THREADS, "%d:%d exit\n",
5062                              proc->pid, thread->pid);
5063                 binder_thread_release(proc, thread);
5064                 thread = NULL;
5065                 break;
5066         case BINDER_VERSION: {
5067                 struct binder_version __user *ver = ubuf;
5068 
5069                 if (size != sizeof(struct binder_version)) {
5070                         ret = -EINVAL;
5071                         goto err;
5072                 }
5073                 if (put_user(BINDER_CURRENT_PROTOCOL_VERSION,
5074                              &ver->protocol_version)) {
5075                         ret = -EINVAL;
5076                         goto err;
5077                 }
5078                 break;
5079         }
5080         case BINDER_GET_NODE_INFO_FOR_REF: {
5081                 struct binder_node_info_for_ref info;
5082 
5083                 if (copy_from_user(&info, ubuf, sizeof(info))) {
5084                         ret = -EFAULT;
5085                         goto err;
5086                 }
5087 
5088                 ret = binder_ioctl_get_node_info_for_ref(proc, &info);
5089                 if (ret < 0)
5090                         goto err;
5091 
5092                 if (copy_to_user(ubuf, &info, sizeof(info))) {
5093                         ret = -EFAULT;
5094                         goto err;
5095                 }
5096 
5097                 break;
5098         }
5099         case BINDER_GET_NODE_DEBUG_INFO: {
5100                 struct binder_node_debug_info info;
5101 
5102                 if (copy_from_user(&info, ubuf, sizeof(info))) {
5103                         ret = -EFAULT;
5104                         goto err;
5105                 }
5106 
5107                 ret = binder_ioctl_get_node_debug_info(proc, &info);
5108                 if (ret < 0)
5109                         goto err;
5110 
5111                 if (copy_to_user(ubuf, &info, sizeof(info))) {
5112                         ret = -EFAULT;
5113                         goto err;
5114                 }
5115                 break;
5116         }
5117         default:
5118                 ret = -EINVAL;
5119                 goto err;
5120         }
5121         ret = 0;
5122 err:
5123         if (thread)
5124                 thread->looper_need_return = false;
5125         wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
5126         if (ret && ret != -ERESTARTSYS)
5127                 pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
5128 err_unlocked:
5129         trace_binder_ioctl_done(ret);
5130         return ret;
5131 }
5132 
5133 static void binder_vma_open(struct vm_area_struct *vma)
5134 {
5135         struct binder_proc *proc = vma->vm_private_data;
5136 
5137         binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5138                      "%d open vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5139                      proc->pid, vma->vm_start, vma->vm_end,
5140                      (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5141                      (unsigned long)pgprot_val(vma->vm_page_prot));
5142 }
5143 
5144 static void binder_vma_close(struct vm_area_struct *vma)
5145 {
5146         struct binder_proc *proc = vma->vm_private_data;
5147 
5148         binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5149                      "%d close vm area %lx-%lx (%ld K) vma %lx pagep %lx\n",
5150                      proc->pid, vma->vm_start, vma->vm_end,
5151                      (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5152                      (unsigned long)pgprot_val(vma->vm_page_prot));
5153         binder_alloc_vma_close(&proc->alloc);
5154 }
5155 
5156 static vm_fault_t binder_vm_fault(struct vm_fault *vmf)
5157 {
5158         return VM_FAULT_SIGBUS;
5159 }
5160 
5161 static const struct vm_operations_struct binder_vm_ops = {
5162         .open = binder_vma_open,
5163         .close = binder_vma_close,
5164         .fault = binder_vm_fault,
5165 };
5166 
5167 static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
5168 {
5169         int ret;
5170         struct binder_proc *proc = filp->private_data;
5171         const char *failure_string;
5172 
5173         if (proc->tsk != current->group_leader)
5174                 return -EINVAL;
5175 
5176         binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5177                      "%s: %d %lx-%lx (%ld K) vma %lx pagep %lx\n",
5178                      __func__, proc->pid, vma->vm_start, vma->vm_end,
5179                      (vma->vm_end - vma->vm_start) / SZ_1K, vma->vm_flags,
5180                      (unsigned long)pgprot_val(vma->vm_page_prot));
5181 
5182         if (vma->vm_flags & FORBIDDEN_MMAP_FLAGS) {
5183                 ret = -EPERM;
5184                 failure_string = "bad vm_flags";
5185                 goto err_bad_arg;
5186         }
5187         vma->vm_flags |= VM_DONTCOPY | VM_MIXEDMAP;
5188         vma->vm_flags &= ~VM_MAYWRITE;
5189 
5190         vma->vm_ops = &binder_vm_ops;
5191         vma->vm_private_data = proc;
5192 
5193         ret = binder_alloc_mmap_handler(&proc->alloc, vma);
5194         if (ret)
5195                 return ret;
5196         return 0;
5197 
5198 err_bad_arg:
5199         pr_err("%s: %d %lx-%lx %s failed %d\n", __func__,
5200                proc->pid, vma->vm_start, vma->vm_end, failure_string, ret);
5201         return ret;
5202 }
5203 
5204 static int binder_open(struct inode *nodp, struct file *filp)
5205 {
5206         struct binder_proc *proc, *itr;
5207         struct binder_device *binder_dev;
5208         struct binderfs_info *info;
5209         struct dentry *binder_binderfs_dir_entry_proc = NULL;
5210         bool existing_pid = false;
5211 
5212         binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__,
5213                      current->group_leader->pid, current->pid);
5214 
5215         proc = kzalloc(sizeof(*proc), GFP_KERNEL);
5216         if (proc == NULL)
5217                 return -ENOMEM;
5218         spin_lock_init(&proc->inner_lock);
5219         spin_lock_init(&proc->outer_lock);
5220         get_task_struct(current->group_leader);
5221         proc->tsk = current->group_leader;
5222         INIT_LIST_HEAD(&proc->todo);
5223         proc->default_priority = task_nice(current);
5224         /* binderfs stashes devices in i_private */
5225         if (is_binderfs_device(nodp)) {
5226                 binder_dev = nodp->i_private;
5227                 info = nodp->i_sb->s_fs_info;
5228                 binder_binderfs_dir_entry_proc = info->proc_log_dir;
5229         } else {
5230                 binder_dev = container_of(filp->private_data,
5231                                           struct binder_device, miscdev);
5232         }
5233         refcount_inc(&binder_dev->ref);
5234         proc->context = &binder_dev->context;
5235         binder_alloc_init(&proc->alloc);
5236 
5237         binder_stats_created(BINDER_STAT_PROC);
5238         proc->pid = current->group_leader->pid;
5239         INIT_LIST_HEAD(&proc->delivered_death);
5240         INIT_LIST_HEAD(&proc->waiting_threads);
5241         filp->private_data = proc;
5242 
5243         mutex_lock(&binder_procs_lock);
5244         hlist_for_each_entry(itr, &binder_procs, proc_node) {
5245                 if (itr->pid == proc->pid) {
5246                         existing_pid = true;
5247                         break;
5248                 }
5249         }
5250         hlist_add_head(&proc->proc_node, &binder_procs);
5251         mutex_unlock(&binder_procs_lock);
5252 
5253         if (binder_debugfs_dir_entry_proc && !existing_pid) {
5254                 char strbuf[11];
5255 
5256                 snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
5257                 /*
5258                  * proc debug entries are shared between contexts.
5259                  * Only create for the first PID to avoid debugfs log spamming
5260                  * The printing code will anyway print all contexts for a given
5261                  * PID so this is not a problem.
5262                  */
5263                 proc->debugfs_entry = debugfs_create_file(strbuf, 0444,
5264                         binder_debugfs_dir_entry_proc,
5265                         (void *)(unsigned long)proc->pid,
5266                         &proc_fops);
5267         }
5268 
5269         if (binder_binderfs_dir_entry_proc && !existing_pid) {
5270                 char strbuf[11];
5271                 struct dentry *binderfs_entry;
5272 
5273                 snprintf(strbuf, sizeof(strbuf), "%u", proc->pid);
5274                 /*
5275                  * Similar to debugfs, the process specific log file is shared
5276                  * between contexts. Only create for the first PID.
5277                  * This is ok since same as debugfs, the log file will contain
5278                  * information on all contexts of a given PID.
5279                  */
5280                 binderfs_entry = binderfs_create_file(binder_binderfs_dir_entry_proc,
5281                         strbuf, &proc_fops, (void *)(unsigned long)proc->pid);
5282                 if (!IS_ERR(binderfs_entry)) {
5283                         proc->binderfs_entry = binderfs_entry;
5284                 } else {
5285                         int error;
5286 
5287                         error = PTR_ERR(binderfs_entry);
5288                         pr_warn("Unable to create file %s in binderfs (error %d)\n",
5289                                 strbuf, error);
5290                 }
5291         }
5292 
5293         return 0;
5294 }
5295 
5296 static int binder_flush(struct file *filp, fl_owner_t id)
5297 {
5298         struct binder_proc *proc = filp->private_data;
5299 
5300         binder_defer_work(proc, BINDER_DEFERRED_FLUSH);
5301 
5302         return 0;
5303 }
5304 
5305 static void binder_deferred_flush(struct binder_proc *proc)
5306 {
5307         struct rb_node *n;
5308         int wake_count = 0;
5309 
5310         binder_inner_proc_lock(proc);
5311         for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n)) {
5312                 struct binder_thread *thread = rb_entry(n, struct binder_thread, rb_node);
5313 
5314                 thread->looper_need_return = true;
5315                 if (thread->looper & BINDER_LOOPER_STATE_WAITING) {
5316                         wake_up_interruptible(&thread->wait);
5317                         wake_count++;
5318                 }
5319         }
5320         binder_inner_proc_unlock(proc);
5321 
5322         binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5323                      "binder_flush: %d woke %d threads\n", proc->pid,
5324                      wake_count);
5325 }
5326 
5327 static int binder_release(struct inode *nodp, struct file *filp)
5328 {
5329         struct binder_proc *proc = filp->private_data;
5330 
5331         debugfs_remove(proc->debugfs_entry);
5332 
5333         if (proc->binderfs_entry) {
5334                 binderfs_remove_file(proc->binderfs_entry);
5335                 proc->binderfs_entry = NULL;
5336         }
5337 
5338         binder_defer_work(proc, BINDER_DEFERRED_RELEASE);
5339 
5340         return 0;
5341 }
5342 
5343 static int binder_node_release(struct binder_node *node, int refs)
5344 {
5345         struct binder_ref *ref;
5346         int death = 0;
5347         struct binder_proc *proc = node->proc;
5348 
5349         binder_release_work(proc, &node->async_todo);
5350 
5351         binder_node_lock(node);
5352         binder_inner_proc_lock(proc);
5353         binder_dequeue_work_ilocked(&node->work);
5354         /*
5355          * The caller must have taken a temporary ref on the node,
5356          */
5357         BUG_ON(!node->tmp_refs);
5358         if (hlist_empty(&node->refs) && node->tmp_refs == 1) {
5359                 binder_inner_proc_unlock(proc);
5360                 binder_node_unlock(node);
5361                 binder_free_node(node);
5362 
5363                 return refs;
5364         }
5365 
5366         node->proc = NULL;
5367         node->local_strong_refs = 0;
5368         node->local_weak_refs = 0;
5369         binder_inner_proc_unlock(proc);
5370 
5371         spin_lock(&binder_dead_nodes_lock);
5372         hlist_add_head(&node->dead_node, &binder_dead_nodes);
5373         spin_unlock(&binder_dead_nodes_lock);
5374 
5375         hlist_for_each_entry(ref, &node->refs, node_entry) {
5376                 refs++;
5377                 /*
5378                  * Need the node lock to synchronize
5379                  * with new notification requests and the
5380                  * inner lock to synchronize with queued
5381                  * death notifications.
5382                  */
5383                 binder_inner_proc_lock(ref->proc);
5384                 if (!ref->death) {
5385                         binder_inner_proc_unlock(ref->proc);
5386                         continue;
5387                 }
5388 
5389                 death++;
5390 
5391                 BUG_ON(!list_empty(&ref->death->work.entry));
5392                 ref->death->work.type = BINDER_WORK_DEAD_BINDER;
5393                 binder_enqueue_work_ilocked(&ref->death->work,
5394                                             &ref->proc->todo);
5395                 binder_wakeup_proc_ilocked(ref->proc);
5396                 binder_inner_proc_unlock(ref->proc);
5397         }
5398 
5399         binder_debug(BINDER_DEBUG_DEAD_BINDER,
5400                      "node %d now dead, refs %d, death %d\n",
5401                      node->debug_id, refs, death);
5402         binder_node_unlock(node);
5403         binder_put_node(node);
5404 
5405         return refs;
5406 }
5407 
5408 static void binder_deferred_release(struct binder_proc *proc)
5409 {
5410         struct binder_context *context = proc->context;
5411         struct binder_device *device;
5412         struct rb_node *n;
5413         int threads, nodes, incoming_refs, outgoing_refs, active_transactions;
5414 
5415         mutex_lock(&binder_procs_lock);
5416         hlist_del(&proc->proc_node);
5417         mutex_unlock(&binder_procs_lock);
5418 
5419         mutex_lock(&context->context_mgr_node_lock);
5420         if (context->binder_context_mgr_node &&
5421             context->binder_context_mgr_node->proc == proc) {
5422                 binder_debug(BINDER_DEBUG_DEAD_BINDER,
5423                              "%s: %d context_mgr_node gone\n",
5424                              __func__, proc->pid);
5425                 context->binder_context_mgr_node = NULL;
5426         }
5427         mutex_unlock(&context->context_mgr_node_lock);
5428         device = container_of(proc->context, struct binder_device, context);
5429         if (refcount_dec_and_test(&device->ref)) {
5430                 kfree(context->name);
5431                 kfree(device);
5432         }
5433         proc->context = NULL;
5434         binder_inner_proc_lock(proc);
5435         /*
5436          * Make sure proc stays alive after we
5437          * remove all the threads
5438          */
5439         proc->tmp_ref++;
5440 
5441         proc->is_dead = true;
5442         threads = 0;
5443         active_transactions = 0;
5444         while ((n = rb_first(&proc->threads))) {
5445                 struct binder_thread *thread;
5446 
5447                 thread = rb_entry(n, struct binder_thread, rb_node);
5448                 binder_inner_proc_unlock(proc);
5449                 threads++;
5450                 active_transactions += binder_thread_release(proc, thread);
5451                 binder_inner_proc_lock(proc);
5452         }
5453 
5454         nodes = 0;
5455         incoming_refs = 0;
5456         while ((n = rb_first(&proc->nodes))) {
5457                 struct binder_node *node;
5458 
5459                 node = rb_entry(n, struct binder_node, rb_node);
5460                 nodes++;
5461                 /*
5462                  * take a temporary ref on the node before
5463                  * calling binder_node_release() which will either
5464                  * kfree() the node or call binder_put_node()
5465                  */
5466                 binder_inc_node_tmpref_ilocked(node);
5467                 rb_erase(&node->rb_node, &proc->nodes);
5468                 binder_inner_proc_unlock(proc);
5469                 incoming_refs = binder_node_release(node, incoming_refs);
5470                 binder_inner_proc_lock(proc);
5471         }
5472         binder_inner_proc_unlock(proc);
5473 
5474         outgoing_refs = 0;
5475         binder_proc_lock(proc);
5476         while ((n = rb_first(&proc->refs_by_desc))) {
5477                 struct binder_ref *ref;
5478 
5479                 ref = rb_entry(n, struct binder_ref, rb_node_desc);
5480                 outgoing_refs++;
5481                 binder_cleanup_ref_olocked(ref);
5482                 binder_proc_unlock(proc);
5483                 binder_free_ref(ref);
5484                 binder_proc_lock(proc);
5485         }
5486         binder_proc_unlock(proc);
5487 
5488         binder_release_work(proc, &proc->todo);
5489         binder_release_work(proc, &proc->delivered_death);
5490 
5491         binder_debug(BINDER_DEBUG_OPEN_CLOSE,
5492                      "%s: %d threads %d, nodes %d (ref %d), refs %d, active transactions %d\n",
5493                      __func__, proc->pid, threads, nodes, incoming_refs,
5494                      outgoing_refs, active_transactions);
5495 
5496         binder_proc_dec_tmpref(proc);
5497 }
5498 
5499 static void binder_deferred_func(struct work_struct *work)
5500 {
5501         struct binder_proc *proc;
5502 
5503         int defer;
5504 
5505         do {
5506                 mutex_lock(&binder_deferred_lock);
5507                 if (!hlist_empty(&binder_deferred_list)) {
5508                         proc = hlist_entry(binder_deferred_list.first,
5509                                         struct binder_proc, deferred_work_node);
5510                         hlist_del_init(&proc->deferred_work_node);
5511                         defer = proc->deferred_work;
5512                         proc->deferred_work = 0;
5513                 } else {
5514                         proc = NULL;
5515                         defer = 0;
5516                 }
5517                 mutex_unlock(&binder_deferred_lock);
5518 
5519                 if (defer & BINDER_DEFERRED_FLUSH)
5520                         binder_deferred_flush(proc);
5521 
5522                 if (defer & BINDER_DEFERRED_RELEASE)
5523                         binder_deferred_release(proc); /* frees proc */
5524         } while (proc);
5525 }
5526 static DECLARE_WORK(binder_deferred_work, binder_deferred_func);
5527 
5528 static void
5529 binder_defer_work(struct binder_proc *proc, enum binder_deferred_state defer)
5530 {
5531         mutex_lock(&binder_deferred_lock);
5532         proc->deferred_work |= defer;
5533         if (hlist_unhashed(&proc->deferred_work_node)) {
5534                 hlist_add_head(&proc->deferred_work_node,
5535                                 &binder_deferred_list);
5536                 schedule_work(&binder_deferred_work);
5537         }
5538         mutex_unlock(&binder_deferred_lock);
5539 }
5540 
5541 static void print_binder_transaction_ilocked(struct seq_file *m,
5542                                              struct binder_proc *proc,
5543                                              const char *prefix,
5544                                              struct binder_transaction *t)
5545 {
5546         struct binder_proc *to_proc;
5547         struct binder_buffer *buffer = t->buffer;
5548 
5549         spin_lock(&t->lock);
5550         to_proc = t->to_proc;
5551         seq_printf(m,
5552                    "%s %d: %pK from %d:%d to %d:%d code %x flags %x pri %ld r%d",
5553                    prefix, t->debug_id, t,
5554                    t->from ? t->from->proc->pid : 0,
5555                    t->from ? t->from->pid : 0,
5556                    to_proc ? to_proc->pid : 0,
5557                    t->to_thread ? t->to_thread->pid : 0,
5558                    t->code, t->flags, t->priority, t->need_reply);
5559         spin_unlock(&t->lock);
5560 
5561         if (proc != to_proc) {
5562                 /*
5563                  * Can only safely deref buffer if we are holding the
5564                  * correct proc inner lock for this node
5565                  */
5566                 seq_puts(m, "\n");
5567                 return;
5568         }
5569 
5570         if (buffer == NULL) {
5571                 seq_puts(m, " buffer free\n");
5572                 return;
5573         }
5574         if (buffer->target_node)
5575                 seq_printf(m, " node %d", buffer->target_node->debug_id);
5576         seq_printf(m, " size %zd:%zd data %pK\n",
5577                    buffer->data_size, buffer->offsets_size,
5578                    buffer->user_data);
5579 }
5580 
5581 static void print_binder_work_ilocked(struct seq_file *m,
5582                                      struct binder_proc *proc,
5583                                      const char *prefix,
5584                                      const char *transaction_prefix,
5585                                      struct binder_work *w)
5586 {
5587         struct binder_node *node;
5588         struct binder_transaction *t;
5589 
5590         switch (w->type) {
5591         case BINDER_WORK_TRANSACTION:
5592                 t = container_of(w, struct binder_transaction, work);
5593                 print_binder_transaction_ilocked(
5594                                 m, proc, transaction_prefix, t);
5595                 break;
5596         case BINDER_WORK_RETURN_ERROR: {
5597                 struct binder_error *e = container_of(
5598                                 w, struct binder_error, work);
5599 
5600                 seq_printf(m, "%stransaction error: %u\n",
5601                            prefix, e->cmd);
5602         } break;
5603         case BINDER_WORK_TRANSACTION_COMPLETE:
5604                 seq_printf(m, "%stransaction complete\n", prefix);
5605                 break;
5606         case BINDER_WORK_NODE:
5607                 node = container_of(w, struct binder_node, work);
5608                 seq_printf(m, "%snode work %d: u%016llx c%016llx\n",
5609                            prefix, node->debug_id,
5610                            (u64)node->ptr, (u64)node->cookie);
5611                 break;
5612         case BINDER_WORK_DEAD_BINDER:
5613                 seq_printf(m, "%shas dead binder\n", prefix);
5614                 break;
5615         case BINDER_WORK_DEAD_BINDER_AND_CLEAR:
5616                 seq_printf(m, "%shas cleared dead binder\n", prefix);
5617                 break;
5618         case BINDER_WORK_CLEAR_DEATH_NOTIFICATION:
5619                 seq_printf(m, "%shas cleared death notification\n", prefix);
5620                 break;
5621         default:
5622                 seq_printf(m, "%sunknown work: type %d\n", prefix, w->type);
5623                 break;
5624         }
5625 }
5626 
5627 static void print_binder_thread_ilocked(struct seq_file *m,
5628                                         struct binder_thread *thread,
5629                                         int print_always)
5630 {
5631         struct binder_transaction *t;
5632         struct binder_work *w;
5633         size_t start_pos = m->count;
5634         size_t header_pos;
5635 
5636         seq_printf(m, "  thread %d: l %02x need_return %d tr %d\n",
5637                         thread->pid, thread->looper,
5638                         thread->looper_need_return,
5639                         atomic_read(&thread->tmp_ref));
5640         header_pos = m->count;
5641         t = thread->transaction_stack;
5642         while (t) {
5643                 if (t->from == thread) {
5644                         print_binder_transaction_ilocked(m, thread->proc,
5645                                         "    outgoing transaction", t);
5646                         t = t->from_parent;
5647                 } else if (t->to_thread == thread) {
5648                         print_binder_transaction_ilocked(m, thread->proc,
5649                                                  "    incoming transaction", t);
5650                         t = t->to_parent;
5651                 } else {
5652                         print_binder_transaction_ilocked(m, thread->proc,
5653                                         "    bad transaction", t);
5654                         t = NULL;
5655                 }
5656         }
5657         list_for_each_entry(w, &thread->todo, entry) {
5658                 print_binder_work_ilocked(m, thread->proc, "    ",
5659                                           "    pending transaction", w);
5660         }
5661         if (!print_always && m->count == header_pos)
5662                 m->count = start_pos;
5663 }
5664 
5665 static void print_binder_node_nilocked(struct seq_file *m,
5666                                        struct binder_node *node)
5667 {
5668         struct binder_ref *ref;
5669         struct binder_work *w;
5670         int count;
5671 
5672         count = 0;
5673         hlist_for_each_entry(ref, &node->refs, node_entry)
5674                 count++;
5675 
5676         seq_printf(m, "  node %d: u%016llx c%016llx hs %d hw %d ls %d lw %d is %d iw %d tr %d",
5677                    node->debug_id, (u64)node->ptr, (u64)node->cookie,
5678                    node->has_strong_ref, node->has_weak_ref,
5679                    node->local_strong_refs, node->local_weak_refs,
5680                    node->internal_strong_refs, count, node->tmp_refs);
5681         if (count) {
5682                 seq_puts(m, " proc");
5683                 hlist_for_each_entry(ref, &node->refs, node_entry)
5684                         seq_printf(m, " %d", ref->proc->pid);
5685         }
5686         seq_puts(m, "\n");
5687         if (node->proc) {
5688                 list_for_each_entry(w, &node->async_todo, entry)
5689                         print_binder_work_ilocked(m, node->proc, "    ",
5690                                           "    pending async transaction", w);
5691         }
5692 }
5693 
5694 static void print_binder_ref_olocked(struct seq_file *m,
5695                                      struct binder_ref *ref)
5696 {
5697         binder_node_lock(ref->node);
5698         seq_printf(m, "  ref %d: desc %d %snode %d s %d w %d d %pK\n",
5699                    ref->data.debug_id, ref->data.desc,
5700                    ref->node->proc ? "" : "dead ",
5701                    ref->node->debug_id, ref->data.strong,
5702                    ref->data.weak, ref->death);
5703         binder_node_unlock(ref->node);
5704 }
5705 
5706 static void print_binder_proc(struct seq_file *m,
5707                               struct binder_proc *proc, int print_all)
5708 {
5709         struct binder_work *w;
5710         struct rb_node *n;
5711         size_t start_pos = m->count;
5712         size_t header_pos;
5713         struct binder_node *last_node = NULL;
5714 
5715         seq_printf(m, "proc %d\n", proc->pid);
5716         seq_printf(m, "context %s\n", proc->context->name);
5717         header_pos = m->count;
5718 
5719         binder_inner_proc_lock(proc);
5720         for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
5721                 print_binder_thread_ilocked(m, rb_entry(n, struct binder_thread,
5722                                                 rb_node), print_all);
5723 
5724         for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n)) {
5725                 struct binder_node *node = rb_entry(n, struct binder_node,
5726                                                     rb_node);
5727                 if (!print_all && !node->has_async_transaction)
5728                         continue;
5729 
5730                 /*
5731                  * take a temporary reference on the node so it
5732                  * survives and isn't removed from the tree
5733                  * while we print it.
5734                  */
5735                 binder_inc_node_tmpref_ilocked(node);
5736                 /* Need to drop inner lock to take node lock */
5737                 binder_inner_proc_unlock(proc);
5738                 if (last_node)
5739                         binder_put_node(last_node);
5740                 binder_node_inner_lock(node);
5741                 print_binder_node_nilocked(m, node);
5742                 binder_node_inner_unlock(node);
5743                 last_node = node;
5744                 binder_inner_proc_lock(proc);
5745         }
5746         binder_inner_proc_unlock(proc);
5747         if (last_node)
5748                 binder_put_node(last_node);
5749 
5750         if (print_all) {
5751                 binder_proc_lock(proc);
5752                 for (n = rb_first(&proc->refs_by_desc);
5753                      n != NULL;
5754                      n = rb_next(n))
5755                         print_binder_ref_olocked(m, rb_entry(n,
5756                                                             struct binder_ref,
5757                                                             rb_node_desc));
5758                 binder_proc_unlock(proc);
5759         }
5760         binder_alloc_print_allocated(m, &proc->alloc);
5761         binder_inner_proc_lock(proc);
5762         list_for_each_entry(w, &proc->todo, entry)
5763                 print_binder_work_ilocked(m, proc, "  ",
5764                                           "  pending transaction", w);
5765         list_for_each_entry(w, &proc->delivered_death, entry) {
5766                 seq_puts(m, "  has delivered dead binder\n");
5767                 break;
5768         }
5769         binder_inner_proc_unlock(proc);
5770         if (!print_all && m->count == header_pos)
5771                 m->count = start_pos;
5772 }
5773 
5774 static const char * const binder_return_strings[] = {
5775         "BR_ERROR",
5776         "BR_OK",
5777         "BR_TRANSACTION",
5778         "BR_REPLY",
5779         "BR_ACQUIRE_RESULT",
5780         "BR_DEAD_REPLY",
5781         "BR_TRANSACTION_COMPLETE",
5782         "BR_INCREFS",
5783         "BR_ACQUIRE",
5784         "BR_RELEASE",
5785         "BR_DECREFS",
5786         "BR_ATTEMPT_ACQUIRE",
5787         "BR_NOOP",
5788         "BR_SPAWN_LOOPER",
5789         "BR_FINISHED",
5790         "BR_DEAD_BINDER",
5791         "BR_CLEAR_DEATH_NOTIFICATION_DONE",
5792         "BR_FAILED_REPLY"
5793 };
5794 
5795 static const char * const binder_command_strings[] = {
5796         "BC_TRANSACTION",
5797         "BC_REPLY",
5798         "BC_ACQUIRE_RESULT",
5799         "BC_FREE_BUFFER",
5800         "BC_INCREFS",
5801         "BC_ACQUIRE",
5802         "BC_RELEASE",
5803         "BC_DECREFS",
5804         "BC_INCREFS_DONE",
5805         "BC_ACQUIRE_DONE",
5806         "BC_ATTEMPT_ACQUIRE",
5807         "BC_REGISTER_LOOPER",
5808         "BC_ENTER_LOOPER",
5809         "BC_EXIT_LOOPER",
5810         "BC_REQUEST_DEATH_NOTIFICATION",
5811         "BC_CLEAR_DEATH_NOTIFICATION",
5812         "BC_DEAD_BINDER_DONE",
5813         "BC_TRANSACTION_SG",
5814         "BC_REPLY_SG",
5815 };
5816 
5817 static const char * const binder_objstat_strings[] = {
5818         "proc",
5819         "thread",
5820         "node",
5821         "ref",
5822         "death",
5823         "transaction",
5824         "transaction_complete"
5825 };
5826 
5827 static void print_binder_stats(struct seq_file *m, const char *prefix,
5828                                struct binder_stats *stats)
5829 {
5830         int i;
5831 
5832         BUILD_BUG_ON(ARRAY_SIZE(stats->bc) !=
5833                      ARRAY_SIZE(binder_command_strings));
5834         for (i = 0; i < ARRAY_SIZE(stats->bc); i++) {
5835                 int temp = atomic_read(&stats->bc[i]);
5836 
5837                 if (temp)
5838                         seq_printf(m, "%s%s: %d\n", prefix,
5839                                    binder_command_strings[i], temp);
5840         }
5841 
5842         BUILD_BUG_ON(ARRAY_SIZE(stats->br) !=
5843                      ARRAY_SIZE(binder_return_strings));
5844         for (i = 0; i < ARRAY_SIZE(stats->br); i++) {
5845                 int temp = atomic_read(&stats->br[i]);
5846 
5847                 if (temp)
5848                         seq_printf(m, "%s%s: %d\n", prefix,
5849                                    binder_return_strings[i], temp);
5850         }
5851 
5852         BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
5853                      ARRAY_SIZE(binder_objstat_strings));
5854         BUILD_BUG_ON(ARRAY_SIZE(stats->obj_created) !=
5855                      ARRAY_SIZE(stats->obj_deleted));
5856         for (i = 0; i < ARRAY_SIZE(stats->obj_created); i++) {
5857                 int created = atomic_read(&stats->obj_created[i]);
5858                 int deleted = atomic_read(&stats->obj_deleted[i]);
5859 
5860                 if (created || deleted)
5861                         seq_printf(m, "%s%s: active %d total %d\n",
5862                                 prefix,
5863                                 binder_objstat_strings[i],
5864                                 created - deleted,
5865                                 created);
5866         }
5867 }
5868 
5869 static void print_binder_proc_stats(struct seq_file *m,
5870                                     struct binder_proc *proc)
5871 {
5872         struct binder_work *w;
5873         struct binder_thread *thread;
5874         struct rb_node *n;
5875         int count, strong, weak, ready_threads;
5876         size_t free_async_space =
5877                 binder_alloc_get_free_async_space(&proc->alloc);
5878 
5879         seq_printf(m, "proc %d\n", proc->pid);
5880         seq_printf(m, "context %s\n", proc->context->name);
5881         count = 0;
5882         ready_threads = 0;
5883         binder_inner_proc_lock(proc);
5884         for (n = rb_first(&proc->threads); n != NULL; n = rb_next(n))
5885                 count++;
5886 
5887         list_for_each_entry(thread, &proc->waiting_threads, waiting_thread_node)
5888                 ready_threads++;
5889 
5890         seq_printf(m, "  threads: %d\n", count);
5891         seq_printf(m, "  requested threads: %d+%d/%d\n"
5892                         "  ready threads %d\n"
5893                         "  free async space %zd\n", proc->requested_threads,
5894                         proc->requested_threads_started, proc->max_threads,
5895                         ready_threads,
5896                         free_async_space);
5897         count = 0;
5898         for (n = rb_first(&proc->nodes); n != NULL; n = rb_next(n))
5899                 count++;
5900         binder_inner_proc_unlock(proc);
5901         seq_printf(m, "  nodes: %d\n", count);
5902         count = 0;
5903         strong = 0;
5904         weak = 0;
5905         binder_proc_lock(proc);
5906         for (n = rb_first(&proc->refs_by_desc); n != NULL; n = rb_next(n)) {
5907                 struct binder_ref *ref = rb_entry(n, struct binder_ref,
5908                                                   rb_node_desc);
5909                 count++;
5910                 strong += ref->data.strong;
5911                 weak += ref->data.weak;
5912         }
5913         binder_proc_unlock(proc);
5914         seq_printf(m, "  refs: %d s %d w %d\n", count, strong, weak);
5915 
5916         count = binder_alloc_get_allocated_count(&proc->alloc);
5917         seq_printf(m, "  buffers: %d\n", count);
5918 
5919         binder_alloc_print_pages(m, &proc->alloc);
5920 
5921         count = 0;
5922         binder_inner_proc_lock(proc);
5923         list_for_each_entry(w, &proc->todo, entry) {
5924                 if (w->type == BINDER_WORK_TRANSACTION)
5925                         count++;
5926         }
5927         binder_inner_proc_unlock(proc);
5928         seq_printf(m, "  pending transactions: %d\n", count);
5929 
5930         print_binder_stats(m, "  ", &proc->stats);
5931 }
5932 
5933 
5934 int binder_state_show(struct seq_file *m, void *unused)
5935 {
5936         struct binder_proc *proc;
5937         struct binder_node *node;
5938         struct binder_node *last_node = NULL;
5939 
5940         seq_puts(m, "binder state:\n");
5941 
5942         spin_lock(&binder_dead_nodes_lock);
5943         if (!hlist_empty(&binder_dead_nodes))
5944                 seq_puts(m, "dead nodes:\n");
5945         hlist_for_each_entry(node, &binder_dead_nodes, dead_node) {
5946                 /*
5947                  * take a temporary reference on the node so it
5948                  * survives and isn't removed from the list
5949                  * while we print it.
5950                  */
5951                 node->tmp_refs++;
5952                 spin_unlock(&binder_dead_nodes_lock);
5953                 if (last_node)
5954                         binder_put_node(last_node);
5955                 binder_node_lock(node);
5956                 print_binder_node_nilocked(m, node);
5957                 binder_node_unlock(node);
5958                 last_node = node;
5959                 spin_lock(&binder_dead_nodes_lock);
5960         }
5961         spin_unlock(&binder_dead_nodes_lock);
5962         if (last_node)
5963                 binder_put_node(last_node);
5964 
5965         mutex_lock(&binder_procs_lock);
5966         hlist_for_each_entry(proc, &binder_procs, proc_node)
5967                 print_binder_proc(m, proc, 1);
5968         mutex_unlock(&binder_procs_lock);
5969 
5970         return 0;
5971 }
5972 
5973 int binder_stats_show(struct seq_file *m, void *unused)
5974 {
5975         struct binder_proc *proc;
5976 
5977         seq_puts(m, "binder stats:\n");
5978 
5979         print_binder_stats(m, "", &binder_stats);
5980 
5981         mutex_lock(&binder_procs_lock);
5982         hlist_for_each_entry(proc, &binder_procs, proc_node)
5983                 print_binder_proc_stats(m, proc);
5984         mutex_unlock(&binder_procs_lock);
5985 
5986         return 0;
5987 }
5988 
5989 int binder_transactions_show(struct seq_file *m, void *unused)
5990 {
5991         struct binder_proc *proc;
5992 
5993         seq_puts(m, "binder transactions:\n");
5994         mutex_lock(&binder_procs_lock);
5995         hlist_for_each_entry(proc, &binder_procs, proc_node)
5996                 print_binder_proc(m, proc, 0);
5997         mutex_unlock(&binder_procs_lock);
5998 
5999         return 0;
6000 }
6001 
6002 static int proc_show(struct seq_file *m, void *unused)
6003 {
6004         struct binder_proc *itr;
6005         int pid = (unsigned long)m->private;
6006 
6007         mutex_lock(&binder_procs_lock);
6008         hlist_for_each_entry(itr, &binder_procs, proc_node) {
6009                 if (itr->pid == pid) {
6010                         seq_puts(m, "binder proc state:\n");
6011                         print_binder_proc(m, itr, 1);
6012                 }
6013         }
6014         mutex_unlock(&binder_procs_lock);
6015 
6016         return 0;
6017 }
6018 
6019 static void print_binder_transaction_log_entry(struct seq_file *m,
6020                                         struct binder_transaction_log_entry *e)
6021 {
6022         int debug_id = READ_ONCE(e->debug_id_done);
6023         /*
6024          * read barrier to guarantee debug_id_done read before
6025          * we print the log values
6026          */
6027         smp_rmb();
6028         seq_printf(m,
6029                    "%d: %s from %d:%d to %d:%d context %s node %d handle %d size %d:%d ret %d/%d l=%d",
6030                    e->debug_id, (e->call_type == 2) ? "reply" :
6031                    ((e->call_type == 1) ? "async" : "call "), e->from_proc,
6032                    e->from_thread, e->to_proc, e->to_thread, e->context_name,
6033                    e->to_node, e->target_handle, e->data_size, e->offsets_size,
6034                    e->return_error, e->return_error_param,
6035                    e->return_error_line);
6036         /*
6037          * read-barrier to guarantee read of debug_id_done after
6038          * done printing the fields of the entry
6039          */
6040         smp_rmb();
6041         seq_printf(m, debug_id && debug_id == READ_ONCE(e->debug_id_done) ?
6042                         "\n" : " (incomplete)\n");
6043 }
6044 
6045 int binder_transaction_log_show(struct seq_file *m, void *unused)
6046 {
6047         struct binder_transaction_log *log = m->private;
6048         unsigned int log_cur = atomic_read(&log->cur);
6049         unsigned int count;
6050         unsigned int cur;
6051         int i;
6052 
6053         count = log_cur + 1;
6054         cur = count < ARRAY_SIZE(log->entry) && !log->full ?
6055                 0 : count % ARRAY_SIZE(log->entry);
6056         if (count > ARRAY_SIZE(log->entry) || log->full)
6057                 count = ARRAY_SIZE(log->entry);
6058         for (i = 0; i < count; i++) {
6059                 unsigned int index = cur++ % ARRAY_SIZE(log->entry);
6060 
6061                 print_binder_transaction_log_entry(m, &log->entry[index]);
6062         }
6063         return 0;
6064 }
6065 
6066 const struct file_operations binder_fops = {
6067         .owner = THIS_MODULE,
6068         .poll = binder_poll,
6069         .unlocked_ioctl = binder_ioctl,
6070         .compat_ioctl = binder_ioctl,
6071         .mmap = binder_mmap,
6072         .open = binder_open,
6073         .flush = binder_flush,
6074         .release = binder_release,
6075 };
6076 
6077 static int __init init_binder_device(const char *name)
6078 {
6079         int ret;
6080         struct binder_device *binder_device;
6081 
6082         binder_device = kzalloc(sizeof(*binder_device), GFP_KERNEL);
6083         if (!binder_device)
6084                 return -ENOMEM;
6085 
6086         binder_device->miscdev.fops = &binder_fops;
6087         binder_device->miscdev.minor = MISC_DYNAMIC_MINOR;
6088         binder_device->miscdev.name = name;
6089 
6090         refcount_set(&binder_device->ref, 1);
6091         binder_device->context.binder_context_mgr_uid = INVALID_UID;
6092         binder_device->context.name = name;
6093         mutex_init(&binder_device->context.context_mgr_node_lock);
6094 
6095         ret = misc_register(&binder_device->miscdev);
6096         if (ret < 0) {
6097                 kfree(binder_device);
6098                 return ret;
6099         }
6100 
6101         hlist_add_head(&binder_device->hlist, &binder_devices);
6102 
6103         return ret;
6104 }
6105 
6106 static int __init binder_init(void)
6107 {
6108         int ret;
6109         char *device_name, *device_tmp;
6110         struct binder_device *device;
6111         struct hlist_node *tmp;
6112         char *device_names = NULL;
6113 
6114         ret = binder_alloc_shrinker_init();
6115         if (ret)
6116                 return ret;
6117 
6118         atomic_set(&binder_transaction_log.cur, ~0U);
6119         atomic_set(&binder_transaction_log_failed.cur, ~0U);
6120 
6121         binder_debugfs_dir_entry_root = debugfs_create_dir("binder", NULL);
6122         if (binder_debugfs_dir_entry_root)
6123                 binder_debugfs_dir_entry_proc = debugfs_create_dir("proc",
6124                                                  binder_debugfs_dir_entry_root);
6125 
6126         if (binder_debugfs_dir_entry_root) {
6127                 debugfs_create_file("state",
6128                                     0444,
6129                                     binder_debugfs_dir_entry_root,
6130                                     NULL,
6131                                     &binder_state_fops);
6132                 debugfs_create_file("stats",
6133                                     0444,
6134                                     binder_debugfs_dir_entry_root,
6135                                     NULL,
6136                                     &binder_stats_fops);
6137                 debugfs_create_file("transactions",
6138                                     0444,
6139                                     binder_debugfs_dir_entry_root,
6140                                     NULL,
6141                                     &binder_transactions_fops);
6142                 debugfs_create_file("transaction_log",
6143                                     0444,
6144                                     binder_debugfs_dir_entry_root,
6145                                     &binder_transaction_log,
6146                                     &binder_transaction_log_fops);
6147                 debugfs_create_file("failed_transaction_log",
6148                                     0444,
6149                                     binder_debugfs_dir_entry_root,
6150                                     &binder_transaction_log_failed,
6151                                     &binder_transaction_log_fops);
6152         }
6153 
6154         if (!IS_ENABLED(CONFIG_ANDROID_BINDERFS) &&
6155             strcmp(binder_devices_param, "") != 0) {
6156                 /*
6157                 * Copy the module_parameter string, because we don't want to
6158                 * tokenize it in-place.
6159                  */
6160                 device_names = kstrdup(binder_devices_param, GFP_KERNEL);
6161                 if (!device_names) {
6162                         ret = -ENOMEM;
6163                         goto err_alloc_device_names_failed;
6164                 }
6165 
6166                 device_tmp = device_names;
6167                 while ((device_name = strsep(&device_tmp, ","))) {
6168                         ret = init_binder_device(device_name);
6169                         if (ret)
6170                                 goto err_init_binder_device_failed;
6171                 }
6172         }
6173 
6174         ret = init_binderfs();
6175         if (ret)
6176                 goto err_init_binder_device_failed;
6177 
6178         return ret;
6179 
6180 err_init_binder_device_failed:
6181         hlist_for_each_entry_safe(device, tmp, &binder_devices, hlist) {
6182                 misc_deregister(&device->miscdev);
6183                 hlist_del(&device->hlist);
6184                 kfree(device);
6185         }
6186 
6187         kfree(device_names);
6188 
6189 err_alloc_device_names_failed:
6190         debugfs_remove_recursive(binder_debugfs_dir_entry_root);
6191 
6192         return ret;
6193 }
6194 
6195 device_initcall(binder_init);
6196 
6197 #define CREATE_TRACE_POINTS
6198 #include "binder_trace.h"
6199 
6200 MODULE_LICENSE("GPL v2");