[IPV4]: Fix nexthop realm dumping for multipath routes

Routing realms exist per nexthop, but are only returned to userspace
for the first nexthop. This is due to the fact that iproute2 only
allows to set the realm for the first nexthop and the kernel refuses
multipath routes where only a single realm is present.

Dump all realms for multipath routes to enable iproute to correctly
display them.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_semantics.c

@@ -961,10 +961,6 @@ fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
 	rtm->rtm_protocol = fi->fib_protocol;
 	if (fi->fib_priority)
 		RTA_PUT(skb, RTA_PRIORITY, 4, &fi->fib_priority);
-#ifdef CONFIG_NET_CLS_ROUTE
-	if (fi->fib_nh[0].nh_tclassid)
-		RTA_PUT(skb, RTA_FLOW, 4, &fi->fib_nh[0].nh_tclassid);
-#endif
 	if (rtnetlink_put_metrics(skb, fi->fib_metrics) < 0)
 		goto rtattr_failure;
 	if (fi->fib_prefsrc)
@@ -974,6 +970,10 @@ fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
 			RTA_PUT(skb, RTA_GATEWAY, 4, &fi->fib_nh->nh_gw);
 		if (fi->fib_nh->nh_oif)
 			RTA_PUT(skb, RTA_OIF, sizeof(int), &fi->fib_nh->nh_oif);
+#ifdef CONFIG_NET_CLS_ROUTE
+		if (fi->fib_nh[0].nh_tclassid)
+			RTA_PUT(skb, RTA_FLOW, 4, &fi->fib_nh[0].nh_tclassid);
+#endif
 	}
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 	if (fi->fib_nhs > 1) {
@@ -992,6 +992,10 @@ fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
 			nhp->rtnh_ifindex = nh->nh_oif;
 			if (nh->nh_gw)
 				RTA_PUT(skb, RTA_GATEWAY, 4, &nh->nh_gw);
+#ifdef CONFIG_NET_CLS_ROUTE
+			if (nh->nh_tclassid)
+				RTA_PUT(skb, RTA_FLOW, 4, &nh->nh_tclassid);
+#endif
 			nhp->rtnh_len = skb->tail - (unsigned char*)nhp;
 		} endfor_nexthops(fi);
 		mp_head->rta_type = RTA_MULTIPATH;