From mboxrd@z Thu Jan  1 00:00:00 1970
From: Timo Teras <timo.teras@iki.fi>
Subject: Re: [PATCH] net: gro: make sure skb->cb[] initial content has not
 to be zero
Date: Fri, 16 May 2014 22:08:22 +0300
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Cc: Eric Dumazet <edumazet@google.com>, netdev@vger.kernel.org,
	Herbert Xu <herbert@gondor.apana.org.au>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, 16 May 2014 11:34:37 -0700
Eric Dumazet <eric.dumazet@gmail.com> wrote:

> From: Eric Dumazet <edumazet@google.com>
>=20
> Starting from linux-3.13, GRO attempts to build full size skbs.
>=20
> Problem is the commit assumed one particular field in skb->cb[]
> was clean, but it is not the case on some stacked devices.
>=20
> Timo reported a crash in case traffic is decrypted before
> reaching a GRE device.
>=20
> Fix this by initializing NAPI_GRO_CB(skb)->last at the right place,
> this also removes one conditional.
>=20
> Thanks a lot to Timo for providing full reports and bisecting this.
>=20
> Fixes: 8a29111c7ca6 ("net: gro: allow to build full sized skb")
> Bisected-by: Timo Teras <timo.teras@iki.fi>
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
> Please Timo test this patch so that we confirm it fixes the bug for
> you.

Yes, everything looks green now! (The test case reproduced the crash
reliably and immediately. Now it's been up and working for more than
tens minutes already :)

Tested-by: Timo Ter=C3=A4s <timo.teras@iki.fi>

Needless to say, this should go to 3.14-stable as well.

Thanks a lot Eric!