From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] ipv6: gro: fix PV6_GRO_CB(skb)->proto problem
Date: Tue, 09 Oct 2012 15:06:25 +0200
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	 <20121008.154148.2288526275691661749.davem@davemloft.net>
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To: David Miller <davem@davemloft.net>
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On Mon, 2012-10-08 at 15:41 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Mon, 08 Oct 2012 21:38:50 +0200
> 
> > From: Eric Dumazet <edumazet@google.com>
> > 
> > It seems IPV6_GRO_CB(skb)->proto can be destroyed in skb_gro_receive()
> > if a new skb is allocated (to serve as an anchor for frag_list)
> > 
> > We copy NAPI_GRO_CB() only (not the IPV6 specific part) in :
> > 
> > *NAPI_GRO_CB(nskb) = *NAPI_GRO_CB(p);
> > 
> > So we leave IPV6_GRO_CB(nskb)->proto to 0 (fresh skb allocation) instead
> > of IPPROTO_TCP (6)
> > 
> > ipv6_gro_complete() isnt able to call ops->gro_complete()
> > [ tcp6_gro_complete() ]
> > 
> > Fix this by moving proto in NAPI_GRO_CB() and getting rid of
> > IPV6_GRO_CB
> > 
> > Signed-off-by: Eric Dumazet <edumazet@google.com>
> > Cc: Herbert Xu <herbert@gondor.apana.org.au>
> 
> Applied and queued up for -stable, thanks Eric.

Hmm, it appears its a false alarm, you can remove it from stable
candidates.

*NAPI_GRO_CB(nskb) = *NAPI_GRO_CB(p);

was in fact redundant with the 

memcpy(new->cb, old->cb, sizeof(old->cb)); 

done in __copy_skb_header()

I'll send a patch to remove this double copy in net-next

Thanks