ipv6: fix route error binding peer in func icmp6_dst_alloc

in func icmp6_dst_alloc,dst_metric_set call ipv6_cow_metrics to set metric.
ipv6_cow_metrics may will call rt6_bind_peer to set rt6_info->rt6i_peer.
So,we should move ipv6_addr_copy before dst_metric_set to make sure rt6_bind_peer success.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/route.c

@@ -1086,11 +1086,10 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
 	rt->dst.output  = ip6_output;
 	dst_set_neighbour(&rt->dst, neigh);
 	atomic_set(&rt->dst.__refcnt, 1);
-	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
-
 	ipv6_addr_copy(&rt->rt6i_dst.addr, addr);
 	rt->rt6i_dst.plen = 128;
 	rt->rt6i_idev     = idev;
+	dst_metric_set(&rt->dst, RTAX_HOPLIMIT, 255);
 
 	spin_lock_bh(&icmp6_dst_lock);
 	rt->dst.next = icmp6_dst_gc_list;