Re: kernel BUG at net/unix/garbage.c:149!"

From: Nikolay Borisov
Date: Wed Aug 24 2016 - 19:30:18 EST

On Thu, Aug 25, 2016 at 12:40 AM, Hannes Frederic Sowa
<hannes@xxxxxxxxxxxxxxxxxxx> wrote:
> On 24.08.2016 16:24, Nikolay Borisov wrote:
> One commit which could have to do with that is
> commit fc64869c48494a401b1fb627c9ecc4e6c1d74b0d
> Author: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
> Date: Wed May 18 19:19:27 2016 +0300
> net: sock: move ->sk_shutdown out of bitfields.
> but that is only a wild guess.
> Which unix_sock did you extract specifically in the url you provided? In
> unix_notinflight we are specifically checking an unix domain socket that
> is itself being transferred over another af_unix domain socket and not
> the unix domain socket being released at this point.

So this is the state of the socket that is being passed to
unix_notinflight. I have a complete crashdump so if you need more info
to diagnose it I'm happy to provide it. I'm not too familiar with the
code in question so I will need a bit of time to grasp what actually
is happening.

> Can you reproduce this and maybe also with a newer kernel?

Unfortunately I cannot reproduce this since it happened on a
production server nor can I change the kernel. But clearly there is
something wrong, and given that this is a stable kernel and no
relevant changes have gone in latest stable I believe the problem
(albeit hardly reproducible) would still persist.

> Thanks for the report,
> Hannes