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  *  Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
   7  */
   8
   9 #include <linux/stacktrace.h>
  10 #include <asm/stacktrace.h>
  11 #include <asm/unwind.h>
  12 #include <asm/kprobes.h>
  13
  14 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
  15                      struct task_struct *task, struct pt_regs *regs)
  16 {
  17         struct unwind_state state;
  18         unsigned long addr;
  19
  20         unwind_for_each_frame(&state, task, regs, 0) {
  21                 addr = unwind_get_return_address(&state);
  22                 if (!addr || !consume_entry(cookie, addr))
  23                         break;
  24         }
  25 }
  26
  27 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
  28                              void *cookie, struct task_struct *task)
  29 {
  30         struct unwind_state state;
  31         unsigned long addr;
  32
  33         unwind_for_each_frame(&state, task, NULL, 0) {
  34                 if (state.stack_info.type != STACK_TYPE_TASK)
  35                         return -EINVAL;
  36
  37                 if (state.regs)
  38                         return -EINVAL;
  39
  40                 addr = unwind_get_return_address(&state);
  41                 if (!addr)
  42                         return -EINVAL;
  43
  44 #ifdef CONFIG_KPROBES
  45                 /*
  46                  * Mark stacktraces with kretprobed functions on them
  47                  * as unreliable.
  48                  */
  49                 if (state.ip == (unsigned long)kretprobe_trampoline)
  50                         return -EINVAL;
  51 #endif
  52
  53                 if (!consume_entry(cookie, addr))
  54                         return -EINVAL;
  55         }
  56
  57         /* Check for stack corruption */
  58         if (unwind_error(&state))
  59                 return -EINVAL;
  60         return 0;
  61 }