From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net] gro: Disable frag0 optimization on IPv6 ext headers
Date: Tue, 10 Jan 2017 21:31:24 -0500 (EST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 10 Jan 2017 12:24:15 -0800

> From: Herbert Xu <herbert@gondor.apana.org.au>
> 
> The GRO fast path caches the frag0 address.  This address becomes
> invalid if frag0 is modified by pskb_may_pull or its variants.
> So whenever that happens we must disable the frag0 optimization.
> 
> This is usually done through the combination of gro_header_hard
> and gro_header_slow, however, the IPv6 extension header path did
> the pulling directly and would continue to use the GRO fast path
> incorrectly.
> 
> This patch fixes it by disabling the fast path when we enter the
> IPv6 extension header path.
> 
> Fixes: 78a478d0efd9 ("gro: Inline skb_gro_header and cache frag0 virtual address")
> Reported-by: Slava Shwartsman <slavash@mellanox.com>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable.