[IPV6] ROUTE: Do not route packets to link-local address on other device.

With help from Wei Dong <weid@np.css.fujitsu.com>.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 5 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index f4fda80a41a2..19c906f6efa1 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -311,12 +311,21 @@ static inline void rt6_probe(struct rt6_info *rt)
 static int inline rt6_check_dev(struct rt6_info *rt, int oif)
 {
         struct net_device *dev = rt->rt6i_dev;
-        if (!oif || dev->ifindex == oif)
+        int ret = 0;
+
+        if (!oif)
                 return 2;
-        if ((dev->flags & IFF_LOOPBACK) &&
-            rt->rt6i_idev && rt->rt6i_idev->dev->ifindex == oif)
-                return 1;
-        return 0;
+        if (dev->flags & IFF_LOOPBACK) {
+                if (!WARN_ON(rt->rt6i_idev == NULL) &&
+                    rt->rt6i_idev->dev->ifindex == oif)
+                        ret = 1;
+                else
+                        return 0;
+        }
+        if (dev->ifindex == oif)
+                return 2;
+
+        return ret;
 }
 
 static int inline rt6_check_neigh(struct rt6_info *rt)