From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nikolay Aleksandrov Subject: [PATCH net 1/3] bonding: Fix race condition between bond_enslave() and bond_3ad_update_lacp_rate() Date: Mon, 18 Feb 2013 18:59:02 +0100 Message-ID: <1361210344-14907-1-git-send-email-nikolay@redhat.com> Cc: davem@davemloft.net, fubar@us.ibm.com, andy@greyhouse.net To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:57557 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756564Ab3BRSB4 (ORCPT ); Mon, 18 Feb 2013 13:01:56 -0500 Sender: netdev-owner@vger.kernel.org List-ID: port->slave can be NULL since it's being initialized in bond_enslave thus dereferencing a NULL pointer in bond_3ad_update_lacp_rate() Also fix a minor bug, which could cause a port not to have AD_STATE_LACP_TIMEOUT since there's no sync between bond_3ad_update_lacp_rate() and bond_3ad_bind_slave(), by changing the read_lock to a write_lock_bh in bond_3ad_update_lacp_rate(). Signed-off-by: Nikolay Aleksandrov --- drivers/net/bonding/bond_3ad.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index a030e63..1720742 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -2494,11 +2494,13 @@ void bond_3ad_update_lacp_rate(struct bonding *bond) struct port *port = NULL; int lacp_fast; - read_lock(&bond->lock); + write_lock_bh(&bond->lock); lacp_fast = bond->params.lacp_fast; bond_for_each_slave(bond, slave, i) { port = &(SLAVE_AD_INFO(slave).port); + if (port->slave == NULL) + continue; __get_state_machine_lock(port); if (lacp_fast) port->actor_oper_port_state |= AD_STATE_LACP_TIMEOUT; @@ -2507,5 +2509,5 @@ void bond_3ad_update_lacp_rate(struct bonding *bond) __release_state_machine_lock(port); } - read_unlock(&bond->lock); + write_unlock_bh(&bond->lock); } -- 1.7.11.7