From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net: adjust skb->truesize in ___pskb_trim()
Date: Fri, 28 Apr 2017 16:07:37 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 26 Apr 2017 09:07:46 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> Andrey found a way to trigger the WARN_ON_ONCE(delta < len) in
> skb_try_coalesce() using syzkaller and a filter attached to a TCP
> socket.
> 
> As we did recently in commit 158f323b9868 ("net: adjust skb->truesize in
> pskb_expand_head()") we can adjust skb->truesize from ___pskb_trim(),
> via a call to skb_condense().
> 
> If all frags were freed, then skb->truesize can be recomputed.
> 
> This call can be done if skb is not yet owned, or destructor is
> sock_edemux().
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Andrey Konovalov <andreyknvl@google.com>

Also applied, thanks Eric.