blob: 78565ae8e6158b9fa03927a847ed17b94ab4e91f [file] [log] [blame]
From f0def145fef650da4e812d4309708e10ae7f0974 Mon Sep 17 00:00:00 2001
From: Benjamin Poirier <bpoirier@cumulusnetworks.com>
Date: Wed, 12 Feb 2020 10:41:07 +0900
Subject: [PATCH] ipv6: Fix nlmsg_flags when splitting a multipath route
commit afecdb376bd81d7e16578f0cfe82a1aec7ae18f3 upstream.
When splitting an RTA_MULTIPATH request into multiple routes and adding the
second and later components, we must not simply remove NLM_F_REPLACE but
instead replace it by NLM_F_CREATE. Otherwise, it may look like the netlink
message was malformed.
For example,
ip route add 2001:db8::1/128 dev dummy0
ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0 \
nexthop via fe80::30:2 dev dummy0
results in the following warnings:
[ 1035.057019] IPv6: RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE
[ 1035.057517] IPv6: NLM_F_CREATE should be set when creating new route
This patch makes the nlmsg sequence look equivalent for __ip6_ins_rt() to
what it would get if the multipath route had been added in multiple netlink
operations:
ip route add 2001:db8::1/128 dev dummy0
ip route change 2001:db8::1/128 nexthop via fe80::30:1 dev dummy0
ip route append 2001:db8::1/128 nexthop via fe80::30:2 dev dummy0
Fixes: 27596472473a ("ipv6: fix ECMP route replacement")
Signed-off-by: Benjamin Poirier <bpoirier@cumulusnetworks.com>
Reviewed-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 32ea5042dd50..39efc63d51d4 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -4559,6 +4559,7 @@ static int ip6_route_multipath_add(struct fib6_config *cfg,
*/
cfg->fc_nlinfo.nlh->nlmsg_flags &= ~(NLM_F_EXCL |
NLM_F_REPLACE);
+ cfg->fc_nlinfo.nlh->nlmsg_flags |= NLM_F_CREATE;
nhn++;
}
--
2.7.4