net/ipv6: need update peer route when modify metric

When we modify the route metric, the peer address's route need also
be updated. Before the fix:

+ ip addr add dev dummy1 2001:db8::1 peer 2001:db8::2 metric 60
+ ip -6 route show dev dummy1
2001:db8::1 proto kernel metric 60 pref medium
2001:db8::2 proto kernel metric 60 pref medium
+ ip addr change dev dummy1 2001:db8::1 peer 2001:db8::2 metric 61
+ ip -6 route show dev dummy1
2001:db8::1 proto kernel metric 61 pref medium
2001:db8::2 proto kernel metric 60 pref medium

After the fix:
+ ip addr change dev dummy1 2001:db8::1 peer 2001:db8::2 metric 61
+ ip -6 route show dev dummy1
2001:db8::1 proto kernel metric 61 pref medium
2001:db8::2 proto kernel metric 61 pref medium

Fixes: cc389405590d ("net/ipv6: Add support for specifying metric of connected routes")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 164c71c54b5c74dbda24b2de852f3024d96cf8ed..4fb72028ca452165ff255cbf2b9ccf256fe951a9 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -4586,12 +4586,14 @@ inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 
 static int modify_prefix_route(struct inet6_ifaddr *ifp,
-                              unsigned long expires, u32 flags)
+                              unsigned long expires, u32 flags,
+                              bool modify_peer)
 {
        struct fib6_info *f6i;
        u32 prio;
 
-       f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
+       f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
+                                       ifp->prefix_len,
                                        ifp->idev->dev, 0, RTF_DEFAULT, true);
        if (!f6i)
                return -ENOENT;
@@ -4602,7 +4604,8 @@ static int modify_prefix_route(struct inet6_ifaddr *ifp,
                ip6_del_rt(dev_net(ifp->idev->dev), f6i);
 
                /* add new one */
-               addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
+               addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
+                                     ifp->prefix_len,
                                      ifp->rt_priority, ifp->idev->dev,
                                      expires, flags, GFP_KERNEL);
        } else {
@@ -4678,7 +4681,7 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
                int rc = -ENOENT;
 
                if (had_prefixroute)
-                       rc = modify_prefix_route(ifp, expires, flags);
+                       rc = modify_prefix_route(ifp, expires, flags, false);
 
                /* prefix route could have been deleted; if so restore it */
                if (rc == -ENOENT) {
@@ -4686,6 +4689,15 @@ static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
                                              ifp->rt_priority, ifp->idev->dev,
                                              expires, flags, GFP_KERNEL);
                }
+
+               if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
+                       rc = modify_prefix_route(ifp, expires, flags, true);
+
+               if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
+                       addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
+                                             ifp->rt_priority, ifp->idev->dev,
+                                             expires, flags, GFP_KERNEL);
+               }
        } else if (had_prefixroute) {
                enum cleanup_prefix_rt_t action;
                unsigned long rt_expires;