From: David Miller <davem@davemloft.net>
To: fleitner@redhat.com
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH] igmp: fix ip_mc_sf_allow race
Date: Sun, 03 Jan 2010 21:54:41 -0800 (PST) [thread overview]
Message-ID: <20100103.215441.43026709.davem@davemloft.net> (raw)
In-Reply-To: <1262183005-28406-1-git-send-email-fleitner@redhat.com>
From: Flavio Leitner <fleitner@redhat.com>
Date: Wed, 30 Dec 2009 12:23:25 -0200
> Almost all igmp functions accessing inet->mc_list are protected by
> rtnl_lock(), but there is one exception which is ip_mc_sf_allow(),
> so there is a chance of either ip_mc_drop_socket or ip_mc_leave_group
> remove an entry while ip_mc_sf_allow is running causing a crash.
>
> Signed-off-by: Flavio Leitner <fleitner@redhat.com>
Have you triggered this in practice or is this due purely
to code inspection?
That new synchronize_rcu() is very expensive and will decrease
the rate at which groups can be joined and left, _especially_
on high cpu count machines.
I do not think it is therefore a suitable problem to this
race, if it does in fact exist.
next prev parent reply other threads:[~2010-01-04 5:54 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-12-30 14:23 [PATCH] igmp: fix ip_mc_sf_allow race Flavio Leitner
2010-01-04 5:54 ` David Miller [this message]
2010-01-04 11:29 ` Flavio Leitner
2010-01-04 13:07 ` Eric Dumazet
2010-01-04 18:51 ` Flavio Leitner
2010-01-04 19:53 ` Eric Dumazet
2010-01-05 0:06 ` David Stevens
2010-01-05 6:55 ` Eric Dumazet
2010-01-05 20:52 ` [PATCH] igmp: fix ip_mc_sf_allow race [v3] Flavio Leitner
2010-01-05 22:36 ` Eric Dumazet
2010-01-05 23:03 ` Stephen Hemminger
2010-01-06 16:40 ` Paul E. McKenney
2010-01-06 17:10 ` Stephen Hemminger
2010-01-06 18:50 ` Paul E. McKenney
2010-01-28 16:13 ` [PATCH] igmp: fix ip_mc_sf_allow race [v5] Flavio Leitner
2010-02-02 15:32 ` David Miller
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