[PATCH 0/1] autofs: fix memory leak of waitqueues in autofs_catatonic_mode

From: Fedor Pchelkin
Date: Sat Feb 11 2023 - 15:00:20 EST


Syzkaller reports the leak [1]. It is reproducible.

The following patch fixes the leak. It was proposed by Takeshi Misawa and
tested by Syzbot.

In other places of the code the waitqueue is freed when its wait_ctr
becomes zero (see autofs_wait_release). So I think it is not actually
supposed that inside autofs_catatonic_mode wait_ctr cannot be decreased to
zero. Please correct me if I'm wrong.

Also, looking at the discussion [2] of the '[PATCH] autofs4: use wake_up()
instead of wake_up_interruptible', shouldn't wake_up_interruptible()
inside autofs_catatonic_mode() be replaced with wake_up()?

[1] https://syzkaller.appspot.com/bug?id=a9412f636e2d733130f8def7975897d0b57f6e37
[2] https://www.spinics.net/lists/autofs/msg01875.html