From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: Fwd: Possible bug in net/ipv4/route.c?
Date: Mon, 05 Jul 2010 15:34:58 +0200
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Cc: yoshfuji@linux-ipv6.org, netdev@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Stephen Hemminger <shemminger@vyatta.com>
To: Herbert Xu <herbert@gondor.apana.org.au>
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Le lundi 05 juillet 2010 =C3=A0 21:22 +0800, Herbert Xu a =C3=A9crit :
> On Mon, Jul 05, 2010 at 02:59:14PM +0200, Eric Dumazet wrote:
> >
> > Why do we clear full 48 bytes skb->cb[] in skb_alloc(), if no proto=
col
> > stack should rely it being zero ?
>=20
> Unless a protocol is allocating the skb itself, then the fact
> that skb_alloc clears skb->cb is no guarantee that the skb->cb
> will be zero.

I see. We could :

Avoid this memset(skb->cb, 0, sizeof(skb->cb)) in fastpath.

or in debug mode, poison it to trigger errors more often.

Thanks