arch/sparc/kernel/signal32.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
invalid_frame_pointer
do_sigreturn32
do_rt_sigreturn32
get_sigframe
flush_signal_insns
setup_frame32
setup_rt_frame32
handle_signal32
syscall_restart32
do_signal32
do_sys32_sigstack
   1 // SPDX-License-Identifier: GPL-2.0
   2 /*  arch/sparc64/kernel/signal32.c
   3  *
   4  *  Copyright (C) 1991, 1992  Linus Torvalds
   5  *  Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  *  Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
   7  *  Copyright (C) 1997 Eddie C. Dost   (ecd@skynet.be)
   8  *  Copyright (C) 1997,1998 Jakub Jelinek   (jj@sunsite.mff.cuni.cz)
   9  */
  10 
  11 #include <linux/sched.h>
  12 #include <linux/kernel.h>
  13 #include <linux/signal.h>
  14 #include <linux/errno.h>
  15 #include <linux/wait.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/unistd.h>
  18 #include <linux/mm.h>
  19 #include <linux/tty.h>
  20 #include <linux/binfmts.h>
  21 #include <linux/compat.h>
  22 #include <linux/bitops.h>
  23 #include <linux/tracehook.h>
  24 
  25 #include <linux/uaccess.h>
  26 #include <asm/ptrace.h>
  27 #include <asm/pgtable.h>
  28 #include <asm/psrcompat.h>
  29 #include <asm/fpumacro.h>
  30 #include <asm/visasm.h>
  31 #include <asm/compat_signal.h>
  32 #include <asm/switch_to.h>
  33 
  34 #include "sigutil.h"
  35 #include "kernel.h"
  36 
  37 /* This magic should be in g_upper[0] for all upper parts
  38  * to be valid.
  39  */
  40 #define SIGINFO_EXTRA_V8PLUS_MAGIC      0x130e269
  41 typedef struct {
  42         unsigned int g_upper[8];
  43         unsigned int o_upper[8];
  44         unsigned int asi;
  45 } siginfo_extra_v8plus_t;
  46 
  47 struct signal_frame32 {
  48         struct sparc_stackf32   ss;
  49         __siginfo32_t           info;
  50         /* __siginfo_fpu_t * */ u32 fpu_save;
  51         unsigned int            insns[2];
  52         unsigned int            extramask[_COMPAT_NSIG_WORDS - 1];
  53         unsigned int            extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
  54         /* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
  55         siginfo_extra_v8plus_t  v8plus;
  56         /* __siginfo_rwin_t * */u32 rwin_save;
  57 } __attribute__((aligned(8)));
  58 
  59 struct rt_signal_frame32 {
  60         struct sparc_stackf32   ss;
  61         compat_siginfo_t        info;
  62         struct pt_regs32        regs;
  63         compat_sigset_t         mask;
  64         /* __siginfo_fpu_t * */ u32 fpu_save;
  65         unsigned int            insns[2];
  66         compat_stack_t          stack;
  67         unsigned int            extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
  68         /* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
  69         siginfo_extra_v8plus_t  v8plus;
  70         /* __siginfo_rwin_t * */u32 rwin_save;
  71 } __attribute__((aligned(8)));
  72 
  73 /* Checks if the fp is valid.  We always build signal frames which are
  74  * 16-byte aligned, therefore we can always enforce that the restore
  75  * frame has that property as well.
  76  */
  77 static bool invalid_frame_pointer(void __user *fp, int fplen)
  78 {
  79         if ((((unsigned long) fp) & 15) ||
  80             ((unsigned long)fp) > 0x100000000ULL - fplen)
  81                 return true;
  82         return false;
  83 }
  84 
  85 void do_sigreturn32(struct pt_regs *regs)
  86 {
  87         struct signal_frame32 __user *sf;
  88         compat_uptr_t fpu_save;
  89         compat_uptr_t rwin_save;
  90         unsigned int psr, ufp;
  91         unsigned int pc, npc;
  92         sigset_t set;
  93         compat_sigset_t seta;
  94         int err, i;
  95         
  96         /* Always make any pending restarted system calls return -EINTR */
  97         current->restart_block.fn = do_no_restart_syscall;
  98 
  99         synchronize_user_stack();
 100 
 101         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 102         sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];
 103 
 104         /* 1. Make sure we are not getting garbage from the user */
 105         if (invalid_frame_pointer(sf, sizeof(*sf)))
 106                 goto segv;
 107 
 108         if (get_user(ufp, &sf->info.si_regs.u_regs[UREG_FP]))
 109                 goto segv;
 110 
 111         if (ufp & 0x7)
 112                 goto segv;
 113 
 114         if (__get_user(pc, &sf->info.si_regs.pc) ||
 115             __get_user(npc, &sf->info.si_regs.npc))
 116                 goto segv;
 117 
 118         if ((pc | npc) & 3)
 119                 goto segv;
 120 
 121         if (test_thread_flag(TIF_32BIT)) {
 122                 pc &= 0xffffffff;
 123                 npc &= 0xffffffff;
 124         }
 125         regs->tpc = pc;
 126         regs->tnpc = npc;
 127 
 128         /* 2. Restore the state */
 129         err = __get_user(regs->y, &sf->info.si_regs.y);
 130         err |= __get_user(psr, &sf->info.si_regs.psr);
 131 
 132         for (i = UREG_G1; i <= UREG_I7; i++)
 133                 err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
 134         if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
 135                 err |= __get_user(i, &sf->v8plus.g_upper[0]);
 136                 if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
 137                         unsigned long asi;
 138 
 139                         for (i = UREG_G1; i <= UREG_I7; i++)
 140                                 err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
 141                         err |= __get_user(asi, &sf->v8plus.asi);
 142                         regs->tstate &= ~TSTATE_ASI;
 143                         regs->tstate |= ((asi & 0xffUL) << 24UL);
 144                 }
 145         }
 146 
 147         /* User can only change condition codes in %tstate. */
 148         regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
 149         regs->tstate |= psr_to_tstate_icc(psr);
 150 
 151         /* Prevent syscall restart.  */
 152         pt_regs_clear_syscall(regs);
 153 
 154         err |= __get_user(fpu_save, &sf->fpu_save);
 155         if (!err && fpu_save)
 156                 err |= restore_fpu_state(regs, compat_ptr(fpu_save));
 157         err |= __get_user(rwin_save, &sf->rwin_save);
 158         if (!err && rwin_save) {
 159                 if (restore_rwin_state(compat_ptr(rwin_save)))
 160                         goto segv;
 161         }
 162         err |= __get_user(seta.sig[0], &sf->info.si_mask);
 163         err |= copy_from_user(&seta.sig[1], &sf->extramask,
 164                               (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
 165         if (err)
 166                 goto segv;
 167 
 168         set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
 169         set_current_blocked(&set);
 170         return;
 171 
 172 segv:
 173         force_sig(SIGSEGV);
 174 }
 175 
 176 asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
 177 {
 178         struct rt_signal_frame32 __user *sf;
 179         unsigned int psr, pc, npc, ufp;
 180         compat_uptr_t fpu_save;
 181         compat_uptr_t rwin_save;
 182         sigset_t set;
 183         int err, i;
 184         
 185         /* Always make any pending restarted system calls return -EINTR */
 186         current->restart_block.fn = do_no_restart_syscall;
 187 
 188         synchronize_user_stack();
 189         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 190         sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];
 191 
 192         /* 1. Make sure we are not getting garbage from the user */
 193         if (invalid_frame_pointer(sf, sizeof(*sf)))
 194                 goto segv;
 195 
 196         if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
 197                 goto segv;
 198 
 199         if (ufp & 0x7)
 200                 goto segv;
 201 
 202         if (__get_user(pc, &sf->regs.pc) || 
 203             __get_user(npc, &sf->regs.npc))
 204                 goto segv;
 205 
 206         if ((pc | npc) & 3)
 207                 goto segv;
 208 
 209         if (test_thread_flag(TIF_32BIT)) {
 210                 pc &= 0xffffffff;
 211                 npc &= 0xffffffff;
 212         }
 213         regs->tpc = pc;
 214         regs->tnpc = npc;
 215 
 216         /* 2. Restore the state */
 217         err = __get_user(regs->y, &sf->regs.y);
 218         err |= __get_user(psr, &sf->regs.psr);
 219         
 220         for (i = UREG_G1; i <= UREG_I7; i++)
 221                 err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
 222         if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
 223                 err |= __get_user(i, &sf->v8plus.g_upper[0]);
 224                 if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
 225                         unsigned long asi;
 226 
 227                         for (i = UREG_G1; i <= UREG_I7; i++)
 228                                 err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
 229                         err |= __get_user(asi, &sf->v8plus.asi);
 230                         regs->tstate &= ~TSTATE_ASI;
 231                         regs->tstate |= ((asi & 0xffUL) << 24UL);
 232                 }
 233         }
 234 
 235         /* User can only change condition codes in %tstate. */
 236         regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
 237         regs->tstate |= psr_to_tstate_icc(psr);
 238 
 239         /* Prevent syscall restart.  */
 240         pt_regs_clear_syscall(regs);
 241 
 242         err |= __get_user(fpu_save, &sf->fpu_save);
 243         if (!err && fpu_save)
 244                 err |= restore_fpu_state(regs, compat_ptr(fpu_save));
 245         err |= get_compat_sigset(&set, &sf->mask);
 246         err |= compat_restore_altstack(&sf->stack);
 247         if (err)
 248                 goto segv;
 249                 
 250         err |= __get_user(rwin_save, &sf->rwin_save);
 251         if (!err && rwin_save) {
 252                 if (restore_rwin_state(compat_ptr(rwin_save)))
 253                         goto segv;
 254         }
 255 
 256         set_current_blocked(&set);
 257         return;
 258 segv:
 259         force_sig(SIGSEGV);
 260 }
 261 
 262 static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 263 {
 264         unsigned long sp;
 265         
 266         regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
 267         sp = regs->u_regs[UREG_FP];
 268         
 269         /*
 270          * If we are on the alternate signal stack and would overflow it, don't.
 271          * Return an always-bogus address instead so we will die with SIGSEGV.
 272          */
 273         if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
 274                 return (void __user *) -1L;
 275 
 276         /* This is the X/Open sanctioned signal stack switching.  */
 277         sp = sigsp(sp, ksig) - framesize;
 278 
 279         /* Always align the stack frame.  This handles two cases.  First,
 280          * sigaltstack need not be mindful of platform specific stack
 281          * alignment.  Second, if we took this signal because the stack
 282          * is not aligned properly, we'd like to take the signal cleanly
 283          * and report that.
 284          */
 285         sp &= ~15UL;
 286 
 287         return (void __user *) sp;
 288 }
 289 
 290 /* The I-cache flush instruction only works in the primary ASI, which
 291  * right now is the nucleus, aka. kernel space.
 292  *
 293  * Therefore we have to kick the instructions out using the kernel
 294  * side linear mapping of the physical address backing the user
 295  * instructions.
 296  */
 297 static void flush_signal_insns(unsigned long address)
 298 {
 299         unsigned long pstate, paddr;
 300         pte_t *ptep, pte;
 301         pgd_t *pgdp;
 302         pud_t *pudp;
 303         pmd_t *pmdp;
 304 
 305         /* Commit all stores of the instructions we are about to flush.  */
 306         wmb();
 307 
 308         /* Disable cross-call reception.  In this way even a very wide
 309          * munmap() on another cpu can't tear down the page table
 310          * hierarchy from underneath us, since that can't complete
 311          * until the IPI tlb flush returns.
 312          */
 313 
 314         __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
 315         __asm__ __volatile__("wrpr %0, %1, %%pstate"
 316                                 : : "r" (pstate), "i" (PSTATE_IE));
 317 
 318         pgdp = pgd_offset(current->mm, address);
 319         if (pgd_none(*pgdp))
 320                 goto out_irqs_on;
 321         pudp = pud_offset(pgdp, address);
 322         if (pud_none(*pudp))
 323                 goto out_irqs_on;
 324         pmdp = pmd_offset(pudp, address);
 325         if (pmd_none(*pmdp))
 326                 goto out_irqs_on;
 327 
 328         ptep = pte_offset_map(pmdp, address);
 329         pte = *ptep;
 330         if (!pte_present(pte))
 331                 goto out_unmap;
 332 
 333         paddr = (unsigned long) page_address(pte_page(pte));
 334 
 335         __asm__ __volatile__("flush     %0 + %1"
 336                              : /* no outputs */
 337                              : "r" (paddr),
 338                                "r" (address & (PAGE_SIZE - 1))
 339                              : "memory");
 340 
 341 out_unmap:
 342         pte_unmap(ptep);
 343 out_irqs_on:
 344         __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
 345 
 346 }
 347 
 348 static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
 349                          sigset_t *oldset)
 350 {
 351         struct signal_frame32 __user *sf;
 352         int i, err, wsaved;
 353         void __user *tail;
 354         int sigframe_size;
 355         u32 psr;
 356         compat_sigset_t seta;
 357 
 358         /* 1. Make sure everything is clean */
 359         synchronize_user_stack();
 360         save_and_clear_fpu();
 361         
 362         wsaved = get_thread_wsaved();
 363 
 364         sigframe_size = sizeof(*sf);
 365         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 366                 sigframe_size += sizeof(__siginfo_fpu_t);
 367         if (wsaved)
 368                 sigframe_size += sizeof(__siginfo_rwin_t);
 369 
 370         sf = (struct signal_frame32 __user *)
 371                 get_sigframe(ksig, regs, sigframe_size);
 372         
 373         if (invalid_frame_pointer(sf, sigframe_size)) {
 374                 if (show_unhandled_signals)
 375                         pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
 376                                 current->comm, current->pid, (unsigned long)sf,
 377                                 regs->tpc, regs->u_regs[UREG_I7]);
 378                 force_sigsegv(ksig->sig);
 379                 return -EINVAL;
 380         }
 381 
 382         tail = (sf + 1);
 383 
 384         /* 2. Save the current process state */
 385         if (test_thread_flag(TIF_32BIT)) {
 386                 regs->tpc &= 0xffffffff;
 387                 regs->tnpc &= 0xffffffff;
 388         }
 389         err  = put_user(regs->tpc, &sf->info.si_regs.pc);
 390         err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
 391         err |= __put_user(regs->y, &sf->info.si_regs.y);
 392         psr = tstate_to_psr(regs->tstate);
 393         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 394                 psr |= PSR_EF;
 395         err |= __put_user(psr, &sf->info.si_regs.psr);
 396         for (i = 0; i < 16; i++)
 397                 err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
 398         err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
 399         err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
 400         for (i = 1; i < 16; i++)
 401                 err |= __put_user(((u32 *)regs->u_regs)[2*i],
 402                                   &sf->v8plus.g_upper[i]);
 403         err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
 404                           &sf->v8plus.asi);
 405 
 406         if (psr & PSR_EF) {
 407                 __siginfo_fpu_t __user *fp = tail;
 408                 tail += sizeof(*fp);
 409                 err |= save_fpu_state(regs, fp);
 410                 err |= __put_user((u64)fp, &sf->fpu_save);
 411         } else {
 412                 err |= __put_user(0, &sf->fpu_save);
 413         }
 414         if (wsaved) {
 415                 __siginfo_rwin_t __user *rwp = tail;
 416                 tail += sizeof(*rwp);
 417                 err |= save_rwin_state(wsaved, rwp);
 418                 err |= __put_user((u64)rwp, &sf->rwin_save);
 419                 set_thread_wsaved(0);
 420         } else {
 421                 err |= __put_user(0, &sf->rwin_save);
 422         }
 423 
 424         /* If these change we need to know - assignments to seta relies on these sizes */
 425         BUILD_BUG_ON(_NSIG_WORDS != 1);
 426         BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
 427         seta.sig[1] = (oldset->sig[0] >> 32);
 428         seta.sig[0] = oldset->sig[0];
 429 
 430         err |= __put_user(seta.sig[0], &sf->info.si_mask);
 431         err |= __copy_to_user(sf->extramask, &seta.sig[1],
 432                               (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
 433 
 434         if (!wsaved) {
 435                 err |= copy_in_user((u32 __user *)sf,
 436                                     (u32 __user *)(regs->u_regs[UREG_FP]),
 437                                     sizeof(struct reg_window32));
 438         } else {
 439                 struct reg_window *rp;
 440 
 441                 rp = &current_thread_info()->reg_window[wsaved - 1];
 442                 for (i = 0; i < 8; i++)
 443                         err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
 444                 for (i = 0; i < 6; i++)
 445                         err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
 446                 err |= __put_user(rp->ins[6], &sf->ss.fp);
 447                 err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
 448         }       
 449         if (err)
 450                 return err;
 451 
 452         /* 3. signal handler back-trampoline and parameters */
 453         regs->u_regs[UREG_FP] = (unsigned long) sf;
 454         regs->u_regs[UREG_I0] = ksig->sig;
 455         regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 456         regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
 457 
 458         /* 4. signal handler */
 459         regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 460         regs->tnpc = (regs->tpc + 4);
 461         if (test_thread_flag(TIF_32BIT)) {
 462                 regs->tpc &= 0xffffffff;
 463                 regs->tnpc &= 0xffffffff;
 464         }
 465 
 466         /* 5. return to kernel instructions */
 467         if (ksig->ka.ka_restorer) {
 468                 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 469         } else {
 470                 unsigned long address = ((unsigned long)&(sf->insns[0]));
 471 
 472                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
 473         
 474                 err  = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
 475                 err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
 476                 if (err)
 477                         return err;
 478                 flush_signal_insns(address);
 479         }
 480         return 0;
 481 }
 482 
 483 static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
 484                             sigset_t *oldset)
 485 {
 486         struct rt_signal_frame32 __user *sf;
 487         int i, err, wsaved;
 488         void __user *tail;
 489         int sigframe_size;
 490         u32 psr;
 491 
 492         /* 1. Make sure everything is clean */
 493         synchronize_user_stack();
 494         save_and_clear_fpu();
 495         
 496         wsaved = get_thread_wsaved();
 497 
 498         sigframe_size = sizeof(*sf);
 499         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 500                 sigframe_size += sizeof(__siginfo_fpu_t);
 501         if (wsaved)
 502                 sigframe_size += sizeof(__siginfo_rwin_t);
 503 
 504         sf = (struct rt_signal_frame32 __user *)
 505                 get_sigframe(ksig, regs, sigframe_size);
 506         
 507         if (invalid_frame_pointer(sf, sigframe_size)) {
 508                 if (show_unhandled_signals)
 509                         pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
 510                                 current->comm, current->pid, (unsigned long)sf,
 511                                 regs->tpc, regs->u_regs[UREG_I7]);
 512                 force_sigsegv(ksig->sig);
 513                 return -EINVAL;
 514         }
 515 
 516         tail = (sf + 1);
 517 
 518         /* 2. Save the current process state */
 519         if (test_thread_flag(TIF_32BIT)) {
 520                 regs->tpc &= 0xffffffff;
 521                 regs->tnpc &= 0xffffffff;
 522         }
 523         err  = put_user(regs->tpc, &sf->regs.pc);
 524         err |= __put_user(regs->tnpc, &sf->regs.npc);
 525         err |= __put_user(regs->y, &sf->regs.y);
 526         psr = tstate_to_psr(regs->tstate);
 527         if (current_thread_info()->fpsaved[0] & FPRS_FEF)
 528                 psr |= PSR_EF;
 529         err |= __put_user(psr, &sf->regs.psr);
 530         for (i = 0; i < 16; i++)
 531                 err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
 532         err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
 533         err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
 534         for (i = 1; i < 16; i++)
 535                 err |= __put_user(((u32 *)regs->u_regs)[2*i],
 536                                   &sf->v8plus.g_upper[i]);
 537         err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
 538                           &sf->v8plus.asi);
 539 
 540         if (psr & PSR_EF) {
 541                 __siginfo_fpu_t __user *fp = tail;
 542                 tail += sizeof(*fp);
 543                 err |= save_fpu_state(regs, fp);
 544                 err |= __put_user((u64)fp, &sf->fpu_save);
 545         } else {
 546                 err |= __put_user(0, &sf->fpu_save);
 547         }
 548         if (wsaved) {
 549                 __siginfo_rwin_t __user *rwp = tail;
 550                 tail += sizeof(*rwp);
 551                 err |= save_rwin_state(wsaved, rwp);
 552                 err |= __put_user((u64)rwp, &sf->rwin_save);
 553                 set_thread_wsaved(0);
 554         } else {
 555                 err |= __put_user(0, &sf->rwin_save);
 556         }
 557 
 558         /* Update the siginfo structure.  */
 559         err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
 560         
 561         /* Setup sigaltstack */
 562         err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
 563 
 564         err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
 565 
 566         if (!wsaved) {
 567                 err |= copy_in_user((u32 __user *)sf,
 568                                     (u32 __user *)(regs->u_regs[UREG_FP]),
 569                                     sizeof(struct reg_window32));
 570         } else {
 571                 struct reg_window *rp;
 572 
 573                 rp = &current_thread_info()->reg_window[wsaved - 1];
 574                 for (i = 0; i < 8; i++)
 575                         err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
 576                 for (i = 0; i < 6; i++)
 577                         err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
 578                 err |= __put_user(rp->ins[6], &sf->ss.fp);
 579                 err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
 580         }
 581         if (err)
 582                 return err;
 583         
 584         /* 3. signal handler back-trampoline and parameters */
 585         regs->u_regs[UREG_FP] = (unsigned long) sf;
 586         regs->u_regs[UREG_I0] = ksig->sig;
 587         regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
 588         regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
 589 
 590         /* 4. signal handler */
 591         regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
 592         regs->tnpc = (regs->tpc + 4);
 593         if (test_thread_flag(TIF_32BIT)) {
 594                 regs->tpc &= 0xffffffff;
 595                 regs->tnpc &= 0xffffffff;
 596         }
 597 
 598         /* 5. return to kernel instructions */
 599         if (ksig->ka.ka_restorer)
 600                 regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
 601         else {
 602                 unsigned long address = ((unsigned long)&(sf->insns[0]));
 603 
 604                 regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
 605         
 606                 /* mov __NR_rt_sigreturn, %g1 */
 607                 err |= __put_user(0x82102065, &sf->insns[0]);
 608 
 609                 /* t 0x10 */
 610                 err |= __put_user(0x91d02010, &sf->insns[1]);
 611                 if (err)
 612                         return err;
 613 
 614                 flush_signal_insns(address);
 615         }
 616         return 0;
 617 }
 618 
 619 static inline void handle_signal32(struct ksignal *ksig, 
 620                                   struct pt_regs *regs)
 621 {
 622         sigset_t *oldset = sigmask_to_save();
 623         int err;
 624 
 625         if (ksig->ka.sa.sa_flags & SA_SIGINFO)
 626                 err = setup_rt_frame32(ksig, regs, oldset);
 627         else
 628                 err = setup_frame32(ksig, regs, oldset);
 629 
 630         signal_setup_done(err, ksig, 0);
 631 }
 632 
 633 static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
 634                                      struct sigaction *sa)
 635 {
 636         switch (regs->u_regs[UREG_I0]) {
 637         case ERESTART_RESTARTBLOCK:
 638         case ERESTARTNOHAND:
 639         no_system_call_restart:
 640                 regs->u_regs[UREG_I0] = EINTR;
 641                 regs->tstate |= TSTATE_ICARRY;
 642                 break;
 643         case ERESTARTSYS:
 644                 if (!(sa->sa_flags & SA_RESTART))
 645                         goto no_system_call_restart;
 646                 /* fallthrough */
 647         case ERESTARTNOINTR:
 648                 regs->u_regs[UREG_I0] = orig_i0;
 649                 regs->tpc -= 4;
 650                 regs->tnpc -= 4;
 651         }
 652 }
 653 
 654 /* Note that 'init' is a special process: it doesn't get signals it doesn't
 655  * want to handle. Thus you cannot kill init even with a SIGKILL even by
 656  * mistake.
 657  */
 658 void do_signal32(struct pt_regs * regs)
 659 {
 660         struct ksignal ksig;
 661         unsigned long orig_i0 = 0;
 662         int restart_syscall = 0;
 663         bool has_handler = get_signal(&ksig);
 664 
 665         if (pt_regs_is_syscall(regs) &&
 666             (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
 667                 restart_syscall = 1;
 668                 orig_i0 = regs->u_regs[UREG_G6];
 669         }
 670 
 671         if (has_handler) {
 672                 if (restart_syscall)
 673                         syscall_restart32(orig_i0, regs, &ksig.ka.sa);
 674                 handle_signal32(&ksig, regs);
 675         } else {
 676                 if (restart_syscall) {
 677                         switch (regs->u_regs[UREG_I0]) {
 678                         case ERESTARTNOHAND:
 679                         case ERESTARTSYS:
 680                         case ERESTARTNOINTR:
 681                                 /* replay the system call when we are done */
 682                                 regs->u_regs[UREG_I0] = orig_i0;
 683                                 regs->tpc -= 4;
 684                                 regs->tnpc -= 4;
 685                                 pt_regs_clear_syscall(regs);
 686                                 /* fall through */
 687                         case ERESTART_RESTARTBLOCK:
 688                                 regs->u_regs[UREG_G1] = __NR_restart_syscall;
 689                                 regs->tpc -= 4;
 690                                 regs->tnpc -= 4;
 691                                 pt_regs_clear_syscall(regs);
 692                         }
 693                 }
 694                 restore_saved_sigmask();
 695         }
 696 }
 697 
 698 struct sigstack32 {
 699         u32 the_stack;
 700         int cur_status;
 701 };
 702 
 703 asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
 704 {
 705         struct sigstack32 __user *ssptr =
 706                 (struct sigstack32 __user *)((unsigned long)(u_ssptr));
 707         struct sigstack32 __user *ossptr =
 708                 (struct sigstack32 __user *)((unsigned long)(u_ossptr));
 709         int ret = -EFAULT;
 710 
 711         /* First see if old state is wanted. */
 712         if (ossptr) {
 713                 if (put_user(current->sas_ss_sp + current->sas_ss_size,
 714                              &ossptr->the_stack) ||
 715                     __put_user(on_sig_stack(sp), &ossptr->cur_status))
 716                         goto out;
 717         }
 718         
 719         /* Now see if we want to update the new state. */
 720         if (ssptr) {
 721                 u32 ss_sp;
 722 
 723                 if (get_user(ss_sp, &ssptr->the_stack))
 724                         goto out;
 725 
 726                 /* If the current stack was set with sigaltstack, don't
 727                  * swap stacks while we are on it.
 728                  */
 729                 ret = -EPERM;
 730                 if (current->sas_ss_sp && on_sig_stack(sp))
 731                         goto out;
 732                         
 733                 /* Since we don't know the extent of the stack, and we don't
 734                  * track onstack-ness, but rather calculate it, we must
 735                  * presume a size.  Ho hum this interface is lossy.
 736                  */
 737                 current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
 738                 current->sas_ss_size = SIGSTKSZ;
 739         }
 740         
 741         ret = 0;
 742 out:
 743         return ret;
 744 }
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root/arch/sparc/kernel/signal32.c

DEFINITIONS
