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| author | Eiichi Tsukata <devel@etsukata.com> | 2019-07-11 11:35:01 +0900 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2019-07-11 08:22:03 +0200 |
| commit | cbf5b73d162b22e044fe0b7d51dcaa33be065253 (patch) | |
| tree | f4baca1e7a79277c48261f22285361808633911b | |
| parent | 7652ac92018536eb807b6c2130100c85f1ba7e3b (diff) | |
| download | linux-rpi-cbf5b73d162b22e044fe0b7d51dcaa33be065253.tar.gz linux-rpi-cbf5b73d162b22e044fe0b7d51dcaa33be065253.tar.bz2 linux-rpi-cbf5b73d162b22e044fe0b7d51dcaa33be065253.zip | |
x86/stacktrace: Prevent infinite loop in arch_stack_walk_user()
arch_stack_walk_user() checks `if (fp == frame.next_fp)` to prevent a
infinite loop by self reference but it's not enogh for circular reference.
Once a lack of return address is found, there is no point to continue the
loop, so break out.
Fixes: 02b67518e2b1 ("tracing: add support for userspace stacktraces in tracing/iter_ctrl")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20190711023501.963-1-devel@etsukata.com
| -rw-r--r-- | arch/x86/kernel/stacktrace.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/arch/x86/kernel/stacktrace.c b/arch/x86/kernel/stacktrace.c index 2abf27d7df6b..4f36d3241faf 100644 --- a/arch/x86/kernel/stacktrace.c +++ b/arch/x86/kernel/stacktrace.c @@ -129,11 +129,9 @@ void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie, break; if ((unsigned long)fp < regs->sp) break; - if (frame.ret_addr) { - if (!consume_entry(cookie, frame.ret_addr, false)) - return; - } - if (fp == frame.next_fp) + if (!frame.ret_addr) + break; + if (!consume_entry(cookie, frame.ret_addr, false)) break; fp = frame.next_fp; } |