From: Tetsuo Handa penguin-kernel@i-love.sakura.ne.jp
commit 4d43d395fed124631ca02356c711facb90185175 upstream.
syzbot found a flush_work() caller who forgot to call INIT_WORK() because that work_struct was allocated by kzalloc() [1]. But the message
INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator.
by lock_map_acquire() is failing to tell that INIT_WORK() is missing.
Since flush_work() without INIT_WORK() is a bug, and INIT_WORK() should set ->func field to non-zero, let's warn if ->func field is zero.
[1] https://syzkaller.appspot.com/bug?id=a5954455fcfa51c29ca2ab55b203076337e1c77...
Signed-off-by: Tetsuo Handa penguin-kernel@I-love.SAKURA.ne.jp Signed-off-by: Tejun Heo tj@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/workqueue.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -2908,6 +2908,9 @@ static bool __flush_work(struct work_str if (WARN_ON(!wq_online)) return false;
+ if (WARN_ON(!work->func)) + return false; + if (!from_cancel) { lock_map_acquire(&work->lockdep_map); lock_map_release(&work->lockdep_map);