Re: [syzbot] KASAN: use-after-free Read in post_one_notification

[Siddh Raman Pant]

On Wed, 03 Aug 2022 03:57:19 +0530  Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
> It appears this was already fixed, so no need for any more activity on this bug:
> 
> #syz fix: watchqueue: make sure to serialize 'wqueue->defunct' properly
> 
> - Eric

It doesn't address the dangling pointer remaining in the watch_queue,
which was the root cause of this crash. The use-after-free happened
because the pipe was freed but a dangling pointer of it remained in
a watch_queue, and an attempt to dereference it was there.

Thanks,
Siddh