net: ipv4: notify when address lifetime changes

if userspace changes lifetime of address, send netlink notification and
call notifier.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/devinet.c

@@ -802,8 +802,10 @@ static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg
 		if (nlh->nlmsg_flags & NLM_F_EXCL ||
 		    !(nlh->nlmsg_flags & NLM_F_REPLACE))
 			return -EEXIST;
-
-		set_ifa_lifetime(ifa_existing, valid_lft, prefered_lft);
+		ifa = ifa_existing;
+		set_ifa_lifetime(ifa, valid_lft, prefered_lft);
+		rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
+		blocking_notifier_call_chain(&inetaddr_chain, NETDEV_UP, ifa);
 	}
 	return 0;
 }