From mboxrd@z Thu Jan  1 00:00:00 1970
From: Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [bpf-net PATCH v2] bpf: sockmap missing NULL psock check
Date: Sun, 7 Jan 2018 00:08:18 +0100
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References: <20180105040209.11195.85577.stgit@john-Precision-Tower-5810>
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To: John Fastabend <john.fastabend@gmail.com>, borkmann@iogearbox.net,
        alexei.starovoitov@gmail.com
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On 01/05/2018 05:02 AM, John Fastabend wrote:
> Add psock NULL check to handle a racing sock event that can get the
> sk_callback_lock before this case but after xchg happens causing the
> refcnt to hit zero and sock user data (psock) to be null and queued
> for garbage collection.
> 
> Also add a comment in the code because this is a bit subtle and
> not obvious in my opinion.
> 
> Signed-off-by: John Fastabend <john.fastabend@gmail.com>

Applied to bpf, thanks John!