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From: David Miller <davem@davemloft.net>
Subject: Re: linux-next: Tree for Aug 7
Date: Wed, 07 Aug 2013 16:27:48 -0700 (PDT)
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From: Phil Sutter <phil@nwl.cc>
Date: Wed, 7 Aug 2013 20:37:58 +0200

> One could simply call skb_push(skb, ETH_HLEN) right after calling
> eth_type_trans(skb, dev) in order to undo the 'data' and 'len'
> adjustment. Not sure if this kind of hack is the right way to go here,
> or if the whole af_packet parses ethernet header discussion should be
> opened again instead.

That's completely pointless work.

Without that header pull, the only two things left that
eth_type_trans() does is set the skb->protocol field and
set skb->dev.

And even the latter has to be done already in an else
branch in the suspect AF_PACKET code.

So this eth_type_trans() call is 2/3 duplicate or unnecessary work,
it's the completely the wrong thing to do.

Look, I'm going to fix this myself, because I'm pretty tired of
waiting for the obvious fix.