From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nikolay Aleksandrov Subject: [PATCH] bonding: fix locking in enslave failure path Date: Mon, 22 Apr 2013 20:12:22 +0200 Message-ID: <1366654342-2715-1-git-send-email-nikolay@redhat.com> Cc: andy@greyhouse.net, fubar@us.ibm.com, davem@davemloft.net To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:9319 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754136Ab3DVSP3 (ORCPT ); Mon, 22 Apr 2013 14:15:29 -0400 Sender: netdev-owner@vger.kernel.org List-ID: In commit 3c5913b53fefc9d9e15a2d0f93042766658d9f3f ("bonding: primary_slave & curr_active_slave are not cleaned on enslave failure") I didn't account for the use of curr_active_slave without curr_slave_lock and since there are such users, we should hold bond->lock for writing while setting it to NULL (in the NULL case we don't need the curr_slave_lock). Keeping the bond lock as to avoid the extra release/acquire cycle. Signed-off-by: Nikolay Aleksandrov --- drivers/net/bonding/bond_main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index dbbea0e..7db40de1 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1915,14 +1915,16 @@ err_detach: bond_detach_slave(bond, new_slave); if (bond->primary_slave == new_slave) bond->primary_slave = NULL; - write_unlock_bh(&bond->lock); if (bond->curr_active_slave == new_slave) { + bond_change_active_slave(bond, NULL); + write_unlock_bh(&bond->lock); read_lock(&bond->lock); write_lock_bh(&bond->curr_slave_lock); - bond_change_active_slave(bond, NULL); bond_select_active_slave(bond); write_unlock_bh(&bond->curr_slave_lock); read_unlock(&bond->lock); + } else { + write_unlock_bh(&bond->lock); } slave_disable_netpoll(new_slave); -- 1.8.1.4