net/ipv6: need update peer route when modify metric
authorHangbin Liu <liuhangbin@gmail.com>
Tue, 3 Mar 2020 06:37:34 +0000 (14:37 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 18 Mar 2020 06:14:17 +0000 (07:14 +0100)
[ Upstream commit 617940123e0140521f3080d2befc2bf55bcda094 ]

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: 8308f3ff1753 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/ipv6/addrconf.c

index b2d83de..e76efa5 100644 (file)
@@ -4535,12 +4535,13 @@ 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,
+       f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
                                        ifp->prefix_len,
                                        ifp->idev->dev,
                                        0, RTF_GATEWAY | RTF_DEFAULT);
@@ -4553,7 +4554,8 @@ 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 {
@@ -4629,7 +4631,7 @@ 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) {
@@ -4637,6 +4639,15 @@ 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;