This source file includes following definitions.
- arch_stack_walk
- arch_stack_walk_reliable
- copy_stack_frame
- arch_stack_walk_user
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6 #include <linux/sched.h>
7 #include <linux/sched/debug.h>
8 #include <linux/sched/task_stack.h>
9 #include <linux/stacktrace.h>
10 #include <linux/export.h>
11 #include <linux/uaccess.h>
12 #include <asm/stacktrace.h>
13 #include <asm/unwind.h>
14
15 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
16 struct task_struct *task, struct pt_regs *regs)
17 {
18 struct unwind_state state;
19 unsigned long addr;
20
21 if (regs && !consume_entry(cookie, regs->ip, false))
22 return;
23
24 for (unwind_start(&state, task, regs, NULL); !unwind_done(&state);
25 unwind_next_frame(&state)) {
26 addr = unwind_get_return_address(&state);
27 if (!addr || !consume_entry(cookie, addr, false))
28 break;
29 }
30 }
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37
38 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
39 void *cookie, struct task_struct *task)
40 {
41 struct unwind_state state;
42 struct pt_regs *regs;
43 unsigned long addr;
44
45 for (unwind_start(&state, task, NULL, NULL);
46 !unwind_done(&state) && !unwind_error(&state);
47 unwind_next_frame(&state)) {
48
49 regs = unwind_get_entry_regs(&state, NULL);
50 if (regs) {
51
52 if (user_mode(regs))
53 return 0;
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61
62 if (IS_ENABLED(CONFIG_FRAME_POINTER))
63 return -EINVAL;
64 }
65
66 addr = unwind_get_return_address(&state);
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71
72
73 if (!addr)
74 return -EINVAL;
75
76 if (!consume_entry(cookie, addr, false))
77 return -EINVAL;
78 }
79
80
81 if (unwind_error(&state))
82 return -EINVAL;
83
84
85 if (!(task->flags & (PF_KTHREAD | PF_IDLE)))
86 return -EINVAL;
87
88 return 0;
89 }
90
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92
93 struct stack_frame_user {
94 const void __user *next_fp;
95 unsigned long ret_addr;
96 };
97
98 static int
99 copy_stack_frame(const void __user *fp, struct stack_frame_user *frame)
100 {
101 int ret;
102
103 if (__range_not_ok(fp, sizeof(*frame), TASK_SIZE))
104 return 0;
105
106 ret = 1;
107 pagefault_disable();
108 if (__copy_from_user_inatomic(frame, fp, sizeof(*frame)))
109 ret = 0;
110 pagefault_enable();
111
112 return ret;
113 }
114
115 void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
116 const struct pt_regs *regs)
117 {
118 const void __user *fp = (const void __user *)regs->bp;
119
120 if (!consume_entry(cookie, regs->ip, false))
121 return;
122
123 while (1) {
124 struct stack_frame_user frame;
125
126 frame.next_fp = NULL;
127 frame.ret_addr = 0;
128 if (!copy_stack_frame(fp, &frame))
129 break;
130 if ((unsigned long)fp < regs->sp)
131 break;
132 if (!frame.ret_addr)
133 break;
134 if (!consume_entry(cookie, frame.ret_addr, false))
135 break;
136 fp = frame.next_fp;
137 }
138 }
139