From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Pirko , "David S. Miller" Subject: [ 69/95] team: check return value of team_get_port_by_index_rcu() for NULL Date: Tue, 25 Jun 2013 11:32:56 -0700 Message-Id: <20130625182201.389801943@linuxfoundation.org> In-Reply-To: <20130625182153.605455184@linuxfoundation.org> References: <20130625182153.605455184@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jiri Pirko [ Upstream commit 76c455decbbad31de21c727edb184a963f42b40b ] team_get_port_by_index_rcu() might return NULL due to race between port removal and skb tx path. Panic is easily triggeable when txing packets and adding/removing port in a loop. introduced by commit 3d249d4ca "net: introduce ethernet teaming device" and commit 753f993911b "team: introduce random mode" (for random mode) Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/team/team_mode_roundrobin.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/net/team/team_mode_roundrobin.c +++ b/drivers/net/team/team_mode_roundrobin.c @@ -52,6 +52,8 @@ static bool rr_transmit(struct team *tea port_index = rr_priv(team)->sent_packets++ % team->en_port_count; port = team_get_port_by_index_rcu(team, port_index); + if (unlikely(!port)) + goto drop; port = __get_first_port_up(team, port); if (unlikely(!port)) goto drop;