Commit 29d64551 authored Jun 01, 2016 by Jann Horn Committed by Linus Torvalds Jun 10, 2016

sched: panic on corrupted stack end



Until now, hitting this BUG_ON caused a recursive oops (because oops
handling involves do_exit(), which calls into the scheduler, which in
turn raises an oops), which caused stuff below the stack to be
overwritten until a panic happened (e.g.  via an oops in interrupt
context, caused by the overwritten CPU index in the thread_info).

Just panic directly.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 2f36db71

kernel/sched/core.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -3047,7 +3047,8 @@ static noinline void __schedule_bug(struct task_struct *prev)
		static inline void schedule_debug(struct task_struct *prev)
		{
		#ifdef CONFIG_SCHED_STACK_END_CHECK
		BUG_ON(task_stack_end_corrupted(prev));
		if (task_stack_end_corrupted(prev))
		panic("corrupted stack end detected inside scheduler\n");
		#endif

		if (unlikely(in_atomic_preempt_off())) {