s390/kernel/stacktrace.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Stack trace management functions
0004  *
0005  *  Copyright IBM Corp. 2006
0006  */
0007
0008 #include <linux/stacktrace.h>
0009 #include <asm/stacktrace.h>
0010 #include <asm/unwind.h>
0011 #include <asm/kprobes.h>
0012
0013 void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
0014              struct task_struct *task, struct pt_regs *regs)
0015 {
0016     struct unwind_state state;
0017     unsigned long addr;
0018
0019     unwind_for_each_frame(&state, task, regs, 0) {
0020         addr = unwind_get_return_address(&state);
0021         if (!addr || !consume_entry(cookie, addr))
0022             break;
0023     }
0024 }
0025
0026 int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry,
0027                  void *cookie, struct task_struct *task)
0028 {
0029     struct unwind_state state;
0030     unsigned long addr;
0031
0032     unwind_for_each_frame(&state, task, NULL, 0) {
0033         if (state.stack_info.type != STACK_TYPE_TASK)
0034             return -EINVAL;
0035
0036         if (state.regs)
0037             return -EINVAL;
0038
0039         addr = unwind_get_return_address(&state);
0040         if (!addr)
0041             return -EINVAL;
0042
0043 #ifdef CONFIG_KPROBES
0044         /*
0045          * Mark stacktraces with kretprobed functions on them
0046          * as unreliable.
0047          */
0048         if (state.ip == (unsigned long)__kretprobe_trampoline)
0049             return -EINVAL;
0050 #endif
0051
0052         if (!consume_entry(cookie, addr))
0053             return -EINVAL;
0054     }
0055
0056     /* Check for stack corruption */
0057     if (unwind_error(&state))
0058         return -EINVAL;
0059     return 0;
0060 }