From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: [PATCH net] bridge: avoid OOPS if root port not found Date: Tue, 30 Apr 2013 08:29:27 -0700 Message-ID: <20130430082927.56aa0785@nehalam.linuxnetplumber.net> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: David Miller Return-path: Received: from mail-pd0-f175.google.com ([209.85.192.175]:33883 "EHLO mail-pd0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932930Ab3D3P3k (ORCPT ); Tue, 30 Apr 2013 11:29:40 -0400 Received: by mail-pd0-f175.google.com with SMTP id g10so367566pdj.20 for ; Tue, 30 Apr 2013 08:29:39 -0700 (PDT) Sender: netdev-owner@vger.kernel.org List-ID: Bridge can crash while trying to send topology change packet. This happens if root port can't be found. This was reported by user but currently unable to reproduce it easily. The STP conditions that cause this are not known yet, but the problem doesn't have to be fatal. Signed-off-by: Stephen Hemminger --- a/net/bridge/br_stp.c 2013-03-07 18:12:53.885287247 -0800 +++ b/net/bridge/br_stp.c 2013-04-30 08:24:05.935771645 -0700 @@ -225,7 +225,14 @@ static void br_record_config_timeout_val /* called under bridge lock */ void br_transmit_tcn(struct net_bridge *br) { - br_send_tcn_bpdu(br_get_port(br, br->root_port)); + struct net_bridge_port *p; + + p = br_get_port(br, br->root_port); + if (p) + br_send_tcn_bpdu(p); + else + br_notice(br, "root port %u not found for topology notice\n", + br->root_port); } /* called under bridge lock */