From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] netlink: use kfree_rcu() in netlink_release()
Date: Thu, 18 Oct 2012 15:36:16 -0400 (EDT)
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Cc: netdev@vger.kernel.org, marcheu@google.com, kliegs@google.com,
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=46rom: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 18 Oct 2012 15:21:55 +0200

> From: Eric Dumazet <edumazet@google.com>
>=20
> On some suspend/resume operations involving wimax device, we have
> noticed some intermittent memory corruptions in netlink code.
>=20
> St=E9phane Marchesin tracked this corruption in netlink_update_listen=
ers()
> and suggested a patch.
>=20
> It appears netlink_release() should use kfree_rcu() instead of kfree(=
)
> for the listeners structure as it may be used by other cpus using RCU
> protection.
>=20
> netlink_release() must set to NULL the listeners pointer when
> it is about to be freed.
>=20
> Also have to protect netlink_update_listeners() and
> netlink_has_listeners() if listeners is NULL.
>=20
> Add a nl_deref_protected() lockdep helper to properly document which
> locks protects us.
>=20
> Reported-by: Jonathan Kliegman <kliegs@google.com>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied and queued up for -stable.