From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Patch net] netrom: fix locking in nr_find_socket()
Date: Sun, 30 Dec 2018 20:24:59 -0800 (PST)
Message-ID: <20181230.202459.1666665500046620349.davem@davemloft.net>
References: <20181229215638.10590-1-xiyou.wangcong@gmail.com>
        <20181229215638.10590-3-xiyou.wangcong@gmail.com>
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From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Sat, 29 Dec 2018 13:56:38 -0800

> nr_find_socket(), nr_find_peer() and nr_find_listener() lock the
> sock after finding it in the global list. However, the call path
> requires BH disabled for the sock lock consistently.
> 
> Actually the locking is unnecessary at this point, we can just hold
> the sock refcnt to make sure it is not gone after we unlock the global
> list, and lock it later only when needed.
> 
> Reported-and-tested-by: syzbot+f621cda8b7e598908efa@syzkaller.appspotmail.com
> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>

Applied and queued up for -stable.