From: Jann Horn Date: Wed, 1 Jun 2016 09:55:07 +0000 (+0200) Subject: sched: panic on corrupted stack end X-Git-Tag: v3.18.54~6 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f5efbbc2bd0a4f30c4f312f9d867ff7ef18df2f9;p=thirdparty%2Fkernel%2Fstable.git sched: panic on corrupted stack end commit 29d6455178a09e1dc340380c582b13356227e8df upstream. 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 Signed-off-by: Linus Torvalds [AmitP: Minor refactoring of upstream changes for linux-3.18.y] Signed-off-by: Amit Pundir Signed-off-by: Greg Kroah-Hartman --- diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5f4c71c5d38e8..a760c9e0353e6 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2709,7 +2709,8 @@ 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(unlikely(task_stack_end_corrupted(prev))); + if (task_stack_end_corrupted(prev)) + panic("corrupted stack end detected inside scheduler\n"); #endif /* * Test if we are atomic. Since do_exit() needs to call into