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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2016-10-26 18:41:51 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-10-27 09:32:38 +0300 |
| commit | b6959a362177053c1c90db6dc1af25b6bddd8548 (patch) | |
| tree | 130057c49063003c48dca7d8697a3726c59d644b /arch/x86/kernel/unwind_frame.c | |
| parent | 0d2b8579add41e08aa1110da864f1071d58e6048 (diff) | |
| download | linux-b6959a362177053c1c90db6dc1af25b6bddd8548.tar.xz | |
x86/unwind: Detect bad stack return address
If __kernel_text_address() doesn't recognize a return address on the
stack, it probably means that it's some generated code which
__kernel_text_address() doesn't know about yet.
Otherwise there's probably some stack corruption.
Either way, warn about it.
Use printk_deferred_once() because the unwinder can be called with the
console lock by lockdep via save_stack_trace().
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2d897898f324e275943b590d160b55e482bba65f.1477496147.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/unwind_frame.c')
| -rw-r--r-- | arch/x86/kernel/unwind_frame.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/arch/x86/kernel/unwind_frame.c b/arch/x86/kernel/unwind_frame.c index 9be9a8f8c5df..5639db619c03 100644 --- a/arch/x86/kernel/unwind_frame.c +++ b/arch/x86/kernel/unwind_frame.c @@ -20,7 +20,15 @@ unsigned long unwind_get_return_address(struct unwind_state *state) addr = ftrace_graph_ret_addr(state->task, &state->graph_idx, *addr_p, addr_p); - return __kernel_text_address(addr) ? addr : 0; + if (!__kernel_text_address(addr)) { + printk_deferred_once(KERN_WARNING + "WARNING: unrecognized kernel stack return address %p at %p in %s:%d\n", + (void *)addr, addr_p, state->task->comm, + state->task->pid); + return 0; + } + + return addr; } EXPORT_SYMBOL_GPL(unwind_get_return_address); |