From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] net-gro: reset skb->truesize in napi_reuse_skb()
Date: Thu, 03 Apr 2014 16:18:34 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 03 Apr 2014 09:28:10 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> Recycling skb always had been very tough...
> 
> This time it appears GRO layer can accumulate skb->truesize
> adjustments made by drivers when they attach a fragment to skb.
> 
> skb_gro_receive() can only subtract from skb->truesize the used part
> of a fragment.
> 
> I spotted this problem seeing TcpExtPruneCalled and
> TcpExtTCPRcvCollapsed that were unexpected with a recent kernel, where
> TCP receive window should be sized properly to accept traffic coming
> from a driver not overshooting skb->truesize.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Nasty...

Applied, thanks Eric.