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Message-ID: <1324541138.2621.45.camel@edumazet-laptop>
Subject: Re: BUG: unable to handle kernel NULL pointer dereference in
 ipv6_select_ident
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Chris Boot <bootc@bootc.net>, lkml <linux-kernel@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>
Date: Thu, 22 Dec 2011 09:05:38 +0100
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Le jeudi 22 décembre 2011 à 08:58 +0100, Steffen Klassert a écrit :
> On Thu, Dec 22, 2011 at 08:51:17AM +0100, Eric Dumazet wrote:
> > 
> > Prior to 618f9bc74a0, we were calling 
> > 
> > static inline u32 dst_mtu(const struct dst_entry *dst)
> >  {
> >        u32 mtu = dst_metric_raw(dst, RTAX_MTU);
> > 
> >        if (!mtu)
> >                mtu = dst->ops->mtu(dst);
> > 
> >        return mtu;
> > }
> > 
> > with dst = fake_rtable
> > 
> > and we did :
> > 
> > dst_init_metrics(&rt->dst, br_dst_default_metrics, true);
> > 
> > so dst_metric_raw(dst, RTAX_MTU) was returning 1500
> > 
> > So bug is new, we dont need to backport this fix.
> > 
> 
> Ok, I see. Thanks for pointing it out!

You're welcome.

By the way we no longer have this 1500 hard coded, not sure it it
matters or not, but it looks better anyway.