From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 net-next] net: take care of cloned skbs in
 tcp_try_coalesce()
Date: Wed, 02 May 2012 21:11:47 -0400 (EDT)
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Cc: alexander.h.duyck@intel.com, alexander.duyck@gmail.com,
	netdev@vger.kernel.org, ncardwell@google.com, therbert@google.com,
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To: eric.dumazet@gmail.com
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 02 May 2012 19:55:58 +0200

> From: Eric Dumazet <edumazet@google.com>
> 
> Before stealing fragments or skb head, we must make sure skbs are not
> cloned.
> 
> Alexander was worried about destination skb being cloned : In bridge
> setups, a driver could be fooled if skb->data_len would not match skb
> nr_frags.
> 
> If source skb is cloned, we must take references on pages instead.
> 
> Bug happened using tcpdump (if not using mmap())
> 
> Introduce kfree_skb_partial() helper to cleanup code.
> 
> Reported-by: Alexander Duyck <alexander.h.duyck@intel.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied.