net: fix netlink address dumping in IPv4/IPv6

When a dump is interrupted at the last device in a hash chain and
then continued, "idx" won't get incremented past s_idx, so s_ip_idx
is not reset when moving on to the next device. This means of all
following devices only the last n - s_ip_idx addresses are dumped.
Tested-by: Pawel Staszewski <pstaszewski@itcare.pl>
Signed-off-by: Patrick McHardy <kaber@trash.net>

net/ipv4/devinet.c

@@ -1194,7 +1194,7 @@ static int inet_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
 			if (idx < s_idx)
 				goto cont;
-			if (idx > s_idx)
+			if (h > s_h || idx > s_idx)
 				s_ip_idx = 0;
 			in_dev = __in_dev_get_rcu(dev);
 			if (!in_dev)

net/ipv6/addrconf.c

@@ -3610,7 +3610,7 @@ static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
 			if (idx < s_idx)
 				goto cont;
-			if (idx > s_idx)
+			if (h > s_h || idx > s_idx)
 				s_ip_idx = 0;
 			ip_idx = 0;
 			if ((idev = __in6_dev_get(dev)) == NULL)