From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752679AbdIIXJD (ORCPT ); Sat, 9 Sep 2017 19:09:03 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43076 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754008AbdIIXEY (ORCPT ); Sat, 9 Sep 2017 19:04:24 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Serhey Popovych" , "David S. Miller" Date: Sat, 09 Sep 2017 22:47:15 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 205/233] ipv6: Do not leak throw route references In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.48-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Serhey Popovych commit 07f615574f8ac499875b21c1142f26308234a92c upstream. While commit 73ba57bfae4a ("ipv6: fix backtracking for throw routes") does good job on error propagation to the fib_rules_lookup() in fib rules core framework that also corrects throw routes handling, it does not solve route reference leakage problem happened when we return -EAGAIN to the fib_rules_lookup() and leave routing table entry referenced in arg->result. If rule with matched throw route isn't last matched in the list we overwrite arg->result losing reference on throw route stored previously forever. We also partially revert commit ab997ad40839 ("ipv6: fix the incorrect return value of throw route") since we never return routing table entry with dst.error == -EAGAIN when CONFIG_IPV6_MULTIPLE_TABLES is on. Also there is no point to check for RTF_REJECT flag since it is always set throw route. Fixes: 73ba57bfae4a ("ipv6: fix backtracking for throw routes") Signed-off-by: Serhey Popovych Signed-off-by: David S. Miller [bwh: Backported to 3.16: commit ab997ad40839 was never applied here and does not need to be reverted] Signed-off-by: Ben Hutchings --- --- a/net/ipv6/fib6_rules.c +++ b/net/ipv6/fib6_rules.c @@ -105,7 +105,8 @@ static int fib6_rule_action(struct fib_r flp6->saddr = saddr; } err = rt->dst.error; - goto out; + if (err != -EAGAIN) + goto out; } again: ip6_rt_put(rt);