diff options
| author | David Rientjes <rientjes@google.com> | 2008-10-26 18:13:59 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-11-06 19:05:50 -0800 |
| commit | df211d2ac9df176d9b9b4b0984f9dcb50ece39fc (patch) | |
| tree | 7a2dc3bf7def1d973edd21806e83390125c8789e /arch | |
| parent | 5e55aa8db085dad1aabb4574c73c23c7ae571e7b (diff) | |
x86: avoid dereferencing beyond stack + THREAD_SIZE
commit e1e23bb0513520035ec934fa3483507cb6648b7c upstream
x86: avoid dereferencing beyond stack + THREAD_SIZE
It's possible for get_wchan() to dereference past task->stack + THREAD_SIZE
while iterating through instruction pointers if fp equals the upper boundary,
causing a kernel panic.
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/process_64.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index e12e0e4dd25..5a7c5392266 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -729,12 +729,12 @@ unsigned long get_wchan(struct task_struct *p) if (!p || p == current || p->state==TASK_RUNNING) return 0; stack = (unsigned long)task_stack_page(p); - if (p->thread.sp < stack || p->thread.sp > stack+THREAD_SIZE) + if (p->thread.sp < stack || p->thread.sp >= stack+THREAD_SIZE) return 0; fp = *(u64 *)(p->thread.sp); do { if (fp < (unsigned long)stack || - fp > (unsigned long)stack+THREAD_SIZE) + fp >= (unsigned long)stack+THREAD_SIZE) return 0; ip = *(u64 *)(fp+8); if (!in_sched_functions(ip)) |