From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] udp: drop head states only when all skb references
 are gone
Date: Thu, 07 Sep 2017 20:03:05 -0700 (PDT)
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From: Paolo Abeni <pabeni@redhat.com>
Date: Wed,  6 Sep 2017 14:44:36 +0200

> After commit 0ddf3fb2c43d ("udp: preserve skb->dst if required
> for IP options processing") we clear the skb head state as soon
> as the skb carrying them is first processed.
> 
> Since the same skb can be processed several times when MSG_PEEK
> is used, we can end up lacking the required head states, and
> eventually oopsing.
> 
> Fix this clearing the skb head state only when processing the
> last skb reference.
> 
> Reported-by: Eric Dumazet <edumazet@google.com>
> Fixes: 0ddf3fb2c43d ("udp: preserve skb->dst if required for IP options processing")
> Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Applied and queued up for -stable, thanks.