From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] net: more accurate network taps in transmit
 path
Date: Wed, 19 Sep 2012 14:16:37 -0400 (EDT)
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Cc: jamie.gloudon@gmail.com, netdev@vger.kernel.org
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Wed, 19 Sep 2012 08:44:49 +0200

> From: Eric Dumazet <edumazet@google.com>
> 
> dev_queue_xmit_nit() should be called right before ndo_start_xmit()
> calls or we might give wrong packet contents to taps users :
> 
> Packet checksum can be changed, or packet can be linearized or
> segmented, and segments partially sent for the later case.
> 
> Also a memory allocation can fail and packet never really hit the
> driver entry point.
> 
> Reported-by: Jamie Gloudon <jamie.gloudon@gmail.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Are you really sure that all the network tap implementations can
handle software GSO segmented skbs using skb->next linkage?

Because that is what they can potentially see after this change.