From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] dccp: do not release listeners too soon
Date: Thu, 03 Nov 2016 16:19:27 -0400 (EDT)
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Cc: andreyknvl@google.com, gerrit@erg.abdn.ac.uk, dccp@vger.kernel.org,
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 02 Nov 2016 17:14:41 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> Andrey Konovalov reported following error while fuzzing with syzkaller :
 ...
> It turns out DCCP calls __sk_receive_skb(), and this broke when
> lookups no longer took a reference on listeners.
> 
> Fix this issue by adding a @refcounted parameter to __sk_receive_skb(),
> so that sock_put() is used only when needed.
> 
> Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood")
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Andrey Konovalov <andreyknvl@google.com>
> Tested-by: Andrey Konovalov <andreyknvl@google.com>

Applied and queued up for -stable.