Re: possible deadlock in sock_hash_free

[John Fastabend]

On 05/28/2018 04:16 PM, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:ÂÂÂ 7a1a98c171ea Merge branch 'bpf-sendmsg-hook'
> git tree:ÂÂÂÂÂÂ bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=131f4067800000
> kernel config:Â https://syzkaller.appspot.com/x/.config?x=e4078980b886800c
> dashboard link: https://syzkaller.appspot.com/bug?extid=83bdee62c80cc044cb1a
> compiler:ÂÂÂÂÂÂ gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=17a0be2f800000
> C reproducer:ÂÂ https://syzkaller.appspot.com/x/repro.c?x=164cf10f800000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+83bdee62c80cc044cb1a@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> 
> ======================================================
> WARNING: possible circular locking dependency detected
> 4.17.0-rc6+ #25 Not tainted
> ------------------------------------------------------

[...]

#syz fix: bpf: sockhash fix omitted bucket lock in sock_close