LXR linux/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
  14void 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
  27int 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}
  62