From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next-2.6] netlink: netlink_recvmsg() fix
Date: Mon, 16 Aug 2010 08:29:32 +0200
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Johannes Berg <johannes@sipsolutions.net>
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Le lundi 16 ao=C3=BBt 2010 =C3=A0 08:22 +0200, Johannes Berg a =C3=A9cr=
it :
> On Mon, 2010-08-16 at 08:10 +0200, Eric Dumazet wrote:
>=20
> > We'll find another way to address the problem.
>=20
> For my understanding: The problem is that the save/restore of the
> frag_list skb can race so a second reader will not see the frag_list =
skb
> because it gets there while it's NULL. This happens with MSG_PEEK, or
> with clones of the SKB since skb_shared_info is invariant across clon=
es.
>=20
> Correct?
>=20

Yes

I believe we should have a mutual exclusion for the critical section.

(setting pointer to NULL, ...., setting pointer back to its orig value)