ipv6: ignore looped-back NA while dad is running

[ipv6] Ignore looped-back NAs while in Duplicate Address Detection

If we send an unsolicited NA shortly after bringing up an
IPv6 address, the duplicate address detection algorithm
fails and the ip stays in tentative mode forever.
This is due a missing check if the NA is looped-back to us.

Signed-off-by: Daniel Walter <dwalter@barracuda.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 92f952d093db6b18196d1887d6ce7cf7977832f5..f057ff312840ae686392ae986d9a4c0469b12083 100644 (file)
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -945,9 +945,10 @@ static void ndisc_recv_na(struct sk_buff *skb)
        }
        ifp = ipv6_get_ifaddr(dev_net(dev), &msg->target, dev, 1);
        if (ifp) {
-               if (ifp->flags & IFA_F_TENTATIVE) {
-                       addrconf_dad_failure(ifp);
-                       return;
+               if (skb->pkt_type != PACKET_LOOPBACK
+                   && (ifp->flags & IFA_F_TENTATIVE)) {
+                               addrconf_dad_failure(ifp);
+                               return;
                }
                /* What should we make now? The advertisement
                   is invalid, but ndisc specs say nothing