From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Help: major pppoe regression since 2.6.35 (panic on first ppp
 conection)?
Date: Thu, 23 Dec 2010 13:12:28 +0100
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References: <20101222110021.GA8985@ff.dom.local>
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Cc: Jarek Poplawski <jarkao2@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux Kernel <linux-kernel@vger.kernel.org>,
	netdev@vger.kernel.org
To: Joel Soete <soete.joel@scarlet.be>
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Le jeudi 23 d=C3=A9cembre 2010 =C3=A0 11:02 +0000, Joel Soete a =C3=A9c=
rit :
> Hello Eric,
>=20
>=20
> On 12/22/2010 04:25 PM, Eric Dumazet wrote:
> [snip]
> >
> > Something overwrites nr_frags in skb_shinfo(skb)
> >
> > As skb_shinfo follows head portion of an skb, something overflows s=
kb
> > head
> >
> > Please try adding some room like in following patch ?
> >
> > diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
> > index e6ba898..adf2834 100644
> > --- a/include/linux/skbuff.h
> > +++ b/include/linux/skbuff.h
> > @@ -187,6 +187,7 @@ enum {
> >    * the end of the header data, ie. at skb->end.
> >    */
> >   struct skb_shared_info {
> > +	char		filler[64];
> >   	unsigned short	nr_frags;
> >   	unsigned short	gso_size;
> >   	/* Warning: this field is not always filled in (UFO)! */
> >
> Sorry for delay but I have good news, I am sending this answer from:
> $ uname -a
> Linux sidh2 2.6.37-rc7-amd64-t1 #1 SMP Thu Dec 23 10:30:27 GMT 2010 x=
86_64 GNU/Linux
>=20
> with your tips ;<) (without kernel had already died)
>=20
> That said how can find stuff overflowing skb head? (all I say, is tha=
t this issue started with 2.6.34-git6???)
>=20
> Thanks a lot,

You're welcome. At least we know were to search. Thanks !

I am taking holidays right now for about 5 days, I guess someone else
might find the bug before me ;)