arch/s390/kernel/stacktrace.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Stack trace management functions
   4  *
   5  *  Copyright IBM Corp. 2006
   6  */
   7
   8 #include <linux/stacktrace.h>
   9 #include <asm/stacktrace.h>
  10 #include <asm/unwind.h>
  11 #include <asm/kprobes.h>
  12
  13 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
  14                      struct task_struct *task, struct pt_regs *regs)
  15 {
  16         struct unwind_state state;
  17         unsigned long addr;
  18
  19         unwind_for_each_frame(&state, task, regs, 0) {
  20                 addr = unwind_get_return_address(&state);
  21                 if (!addr || !consume_entry(cookie, addr))
  22                         break;
  23         }
  24 }
  25
  26 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
  27                              void *cookie, struct task_struct *task)
  28 {
  29         struct unwind_state state;
  30         unsigned long addr;
  31
  32         unwind_for_each_frame(&state, task, NULL, 0) {
  33                 if (state.stack_info.type != STACK_TYPE_TASK)
  34                         return -EINVAL;
  35
  36                 if (state.regs)
  37                         return -EINVAL;
  38
  39                 addr = unwind_get_return_address(&state);
  40                 if (!addr)
  41                         return -EINVAL;
  42
  43 #ifdef CONFIG_KPROBES
  44                 /*
  45                  * Mark stacktraces with kretprobed functions on them
  46                  * as unreliable.
  47                  */
  48                 if (state.ip == (unsigned long)__kretprobe_trampoline)
  49                         return -EINVAL;
  50 #endif
  51
  52                 if (!consume_entry(cookie, addr))
  53                         return -EINVAL;
  54         }
  55
  56         /* Check for stack corruption */
  57         if (unwind_error(&state))
  58                 return -EINVAL;
  59         return 0;
  60 }