ipv6: do not send RTM_DELADDR for tentative addresses

RTM_NEWADDR notification is sent when IFA_F_TENTATIVE is cleared from
the address. So if the address is added and deleted before DAD probes
completes, the RTM_DELADDR will be sent for which there was no
RTM_NEWADDR causing asymmetry in notification. However if the same
logic is used while sending RTM_DELADDR notification, this asymmetry
can be avoided.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
CC: Patrick McHardy <kaber@trash.net>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index c1e124b..ac9bd56 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -4888,6 +4888,13 @@ static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
        struct net *net = dev_net(ifa->idev->dev);
        int err = -ENOBUFS;
 
+       /* Don't send DELADDR notification for TENTATIVE address,
+        * since NEWADDR notification is sent only after removing
+        * TENTATIVE flag.
+        */
+       if (ifa->flags & IFA_F_TENTATIVE && event == RTM_DELADDR)
+               return;
+
        skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
        if (!skb)
                goto errout;