[ 074/143] ipv6: use rt6_get_dflt_router to get default router in rt6_route_rcv

Willy Tarreau
2014-05-12T01:44:37Z

From: Duan Jiong <duanj.fnst@cn.fujitsu.com>

[ Upstream commit f104a567e673f382b09542a8dc3500aa689957b4 ]

As the rfc 4191 said, the Router Preference and Lifetime values in a
::/0 Route Information Option should override the preference and lifetime
values in the Router Advertisement header. But when the kernel deals with
a ::/0 Route Information Option, the rt6_get_route_info() always return
NULL, that means that overriding will not happen, because those default
routers were added without flag RTF_ROUTEINFO in rt6_add_dflt_router().

In order to deal with that condition, we should call rt6_get_dflt_router
when the prefix length is 0.

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
net/ipv6/route.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index e307517..5af0d1e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -495,8 +495,11 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
prefix = &prefix_buf;
}

- rt = rt6_get_route_info(net, prefix, rinfo->prefix_len, gwaddr,
- dev->ifindex);
+ if (rinfo->prefix_len == 0)
+ rt = rt6_get_dflt_router(gwaddr, dev);
+ else
+ rt = rt6_get_route_info(net, prefix, rinfo->prefix_len,
+ gwaddr, dev->ifindex);

if (rt && !lifetime) {
ip6_del_rt(rt);
--
1.7.12.2.21.g234cd45.dirty