From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin KaFai Lau Subject: [PATCH net-next 2/5] ipv6: Extend the route lookups to low priority metrics. Date: Tue, 28 Apr 2015 13:03:04 -0700 Message-ID: <1430251387-2942539-3-git-send-email-kafai@fb.com> References: <1430251387-2942539-1-git-send-email-kafai@fb.com> Mime-Version: 1.0 Content-Type: text/plain Cc: Hannes Frederic Sowa , Steffen Klassert , David Miller , Yang Yingliang , shengyong , Kernel Team To: netdev Return-path: Received: from mx0b-00082601.pphosted.com ([67.231.153.30]:8543 "EHLO mx0b-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1031041AbbD1UD1 (ORCPT ); Tue, 28 Apr 2015 16:03:27 -0400 Received: from pps.filterd (m0004060 [127.0.0.1]) by mx0b-00082601.pphosted.com (8.14.5/8.14.5) with SMTP id t3SK16gn023335 for ; Tue, 28 Apr 2015 13:03:27 -0700 Received: from mail.thefacebook.com ([199.201.64.23]) by mx0b-00082601.pphosted.com with ESMTP id 1u2gpw01gd-3 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT) for ; Tue, 28 Apr 2015 13:03:27 -0700 Received: from facebook.com (2401:db00:20:7029:face:0:33:0) by mx-out.facebook.com (10.212.232.59) with ESMTP id a0eda9daede111e4bc5a0002c991e86a-6c7f32c0 for ; Tue, 28 Apr 2015 13:03:25 -0700 In-Reply-To: <1430251387-2942539-1-git-send-email-kafai@fb.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Steffen Klassert We search only for routes with highest priority metric in find_rr_leaf(). However if one of these routes is marked as invalid, we may fail to find a route even if there is a appropriate route with lower priority. Then we loose connectivity until the garbage collector deletes the invalid route. This typically happens if a host route expires afer a pmtu event. Fix this by searching also for routes with a lower priority metric. Signed-off-by: Steffen Klassert Signed-off-by: Martin KaFai Lau Reviewed-by: Hannes Frederic Sowa --- net/ipv6/route.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 4774f13..07562a2 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -652,15 +652,33 @@ static struct rt6_info *find_rr_leaf(struct fib6_node *fn, u32 metric, int oif, int strict, bool *do_rr) { - struct rt6_info *rt, *match; + struct rt6_info *rt, *match, *cont; int mpri = -1; match = NULL; - for (rt = rr_head; rt && rt->rt6i_metric == metric; - rt = rt->dst.rt6_next) + cont = NULL; + for (rt = rr_head; rt; rt = rt->dst.rt6_next) { + if (rt->rt6i_metric != metric) { + cont = rt; + break; + } + + match = find_match(rt, oif, strict, &mpri, match, do_rr); + } + + for (rt = fn->leaf; rt && rt != rr_head; rt = rt->dst.rt6_next) { + if (rt->rt6i_metric != metric) { + cont = rt; + break; + } + match = find_match(rt, oif, strict, &mpri, match, do_rr); - for (rt = fn->leaf; rt && rt != rr_head && rt->rt6i_metric == metric; - rt = rt->dst.rt6_next) + } + + if (match || !cont) + return match; + + for (rt = cont; rt; rt = rt->dst.rt6_next) match = find_match(rt, oif, strict, &mpri, match, do_rr); return match; -- 1.8.1