From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [BUG] ipv6: all routes share same inetpeer
Date: Tue, 19 Jul 2011 20:57:50 +0200
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To: David Miller <davem@davemloft.net>
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Le mardi 19 juillet 2011 =C3=A0 20:20 +0200, Eric Dumazet a =C3=A9crit =
:
> Le mardi 19 juillet 2011 =C3=A0 10:37 -0700, David Miller a =C3=A9cri=
t :
> > From: Eric Dumazet <eric.dumazet@gmail.com>
> > Date: Tue, 19 Jul 2011 19:23:49 +0200
> >=20
> > > Maybe you can find the bug before me ?
> >=20
> > I think when we add the route we cow the metrics almost immediately=
=2E
> > The daddr is, unfortunately, fully prefixed at that point.
>=20
> Yes, we shall provide a second ip6_rt_copy() argument, with the
> destination address.
>=20

Hmm, or maybe just change the dst_copy_metrics(&rt->dst, &ort->dst);
call done from ip6_rt_copy(), to avoid doing the COW if not really
needed ?

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ddef80f..5403cea 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1740,7 +1740,7 @@ static struct rt6_info * ip6_rt_copy(struct rt6_i=
nfo *ort)
 		rt->dst.input =3D ort->dst.input;
 		rt->dst.output =3D ort->dst.output;
=20
-		dst_copy_metrics(&rt->dst, &ort->dst);
+		rt->dst._metrics =3D ort->dst._metrics;
 		rt->dst.error =3D ort->dst.error;
 		rt->rt6i_idev =3D ort->rt6i_idev;
 		if (rt->rt6i_idev)