[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <658213cf198a3_96d8820886@john.notmuch>
Date: Tue, 19 Dec 2023 14:06:07 -0800
From: John Fastabend <john.fastabend@...il.com>
To: John Fastabend <john.fastabend@...il.com>,
John Fastabend <john.fastabend@...il.com>,
Kuniyuki Iwashima <kuniyu@...zon.com>,
xrivendell7@...il.com
Cc: alexander@...alicyn.com,
bpf@...r.kernel.org,
daan.j.demeyer@...il.com,
davem@...emloft.net,
dhowells@...hat.com,
edumazet@...gle.com,
john.fastabend@...il.com,
kuba@...nel.org,
kuniyu@...zon.com,
linux-kernel@...r.kernel.org,
netdev@...r.kernel.org,
pabeni@...hat.com
Subject: Re: memory leak in unix_create1/copy_process/security_prepare_creds
John Fastabend wrote:
> John Fastabend wrote:
> > Kuniyuki Iwashima wrote:
> > > From: xingwei lee <xrivendell7@...il.com>
> > > Date: Tue, 19 Dec 2023 17:12:25 +0800
> > > > Hello I found a bug in net/af_unix in the lastest upstream linux
> > > > 6.7.rc5 and comfired in lastest net/net-next/bpf/bpf-next tree.
> > > > Titled "TITLE: memory leak in unix_create1” and I also upload the
> > > > repro.c and repro.txt.
> > > >
> > > > If you fix this issue, please add the following tag to the commit:
> > > > Reported-by: xingwei Lee <xrivendell7@...il.com>
> > >
> > > Thanks for reporting!
> > >
> > > It seems 8866730aed510 forgot to add sock_put().
> > > I've confirmed that the diff below silenced kmemleak but will check
> > > more before posting a patch.
> >
> > Did it really silence the memleak?
>
> Yes reverting the patch fixed the issue for me.
The problem is we call proto update twice that bumps the refcnt
when adding a the same element to the map in the same slot. I'll fix
this on sockmap side so we can keep the current af_unix logic. Should
be able to push a fix tomorrow.
We probably never noticed for other socket types because its an
unusal replace to do same sock/same slot, but af_unix has this
side effect of incrementing the refcnt that doesn't exist elsewhere.
Thanks,
John
Powered by blists - more mailing lists