diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 5ecb56522f9d..ba28aeb7cade 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -42,24 +42,29 @@ static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
 {
 	struct inet_sock *inet = inet_sk(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
+	int oif = sk->sk_bound_dev_if;
 
 	memset(fl6, 0, sizeof(*fl6));
 	fl6->flowi6_proto = sk->sk_protocol;
 	fl6->daddr = sk->sk_v6_daddr;
 	fl6->saddr = np->saddr;
-	fl6->flowi6_oif = sk->sk_bound_dev_if;
 	fl6->flowi6_mark = sk->sk_mark;
 	fl6->fl6_dport = inet->inet_dport;
 	fl6->fl6_sport = inet->inet_sport;
 	fl6->flowlabel = np->flow_label;
 	fl6->flowi6_uid = sk->sk_uid;
 
-	if (!fl6->flowi6_oif)
-		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
+	if (!oif)
+		oif = np->sticky_pktinfo.ipi6_ifindex;
 
-	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
-		fl6->flowi6_oif = np->mcast_oif;
+	if (!oif) {
+		if (ipv6_addr_is_multicast(&fl6->daddr))
+			oif = np->mcast_oif;
+		else
+			oif = np->ucast_oif;
+	}
 
+	fl6->flowi6_oif = oif;
 	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 }