[UDP/TCP]: Fix binding conflict tests wrt. SO_BINDTODEVICE.

net/ipv4/tcp_ipv4.c

@@ -188,7 +188,9 @@ static inline int tcp_bind_conflict(struct sock *sk, struct tcp_bind_bucket *tb)
 	sk_for_each_bound(sk2, node, &tb->owners) {
 		if (sk != sk2 &&
 		    !ipv6_only_sock(sk2) &&
-		    sk->sk_bound_dev_if == sk2->sk_bound_dev_if) {
+		    (!sk->sk_bound_dev_if ||
+		     !sk2->sk_bound_dev_if ||
+		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) {
 			if (!reuse || !sk2->sk_reuse ||
 			    sk2->sk_state == TCP_LISTEN) {
 				struct inet_opt *inet2 = inet_sk(sk2);

net/ipv4/udp.c

@@ -176,7 +176,9 @@ static int udp_v4_get_port(struct sock *sk, unsigned short snum)
 			if (inet2->num == snum &&
 			    sk2 != sk &&
 			    !ipv6_only_sock(sk2) &&
-			    sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
+			    (!sk2->bound_dev_if ||
+			     !sk->bound_dev_if ||
+			     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 			    (!inet2->rcv_saddr ||
 			     !inet->rcv_saddr ||
 			     inet2->rcv_saddr == inet->rcv_saddr) &&

net/ipv6/tcp_ipv6.c

@@ -101,7 +101,10 @@ static inline int tcp_v6_bind_conflict(struct sock *sk,
 
 	/* We must walk the whole port owner list in this case. -DaveM */
 	sk_for_each_bound(sk2, node, &tb->owners) {
-		if (sk != sk2 && sk->sk_bound_dev_if == sk2->sk_bound_dev_if &&
+		if (sk != sk2 &&
+		    (!sk->sk_bound_dev_if ||
+		     !sk2->sk_bound_dev_if ||
+		     sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
 		    (!sk->sk_reuse || !sk2->sk_reuse ||
 		     sk2->sk_state == TCP_LISTEN) &&
 		     ipv6_rcv_saddr_equal(sk, sk2))

net/ipv6/udp.c

@@ -112,7 +112,9 @@ static int udp_v6_get_port(struct sock *sk, unsigned short snum)
 			    &udp_hash[snum & (UDP_HTABLE_SIZE - 1)]) {
 			if (inet_sk(sk2)->num == snum &&
 			    sk2 != sk &&
-			    sk2->sk_bound_dev_if == sk->sk_bound_dev_if &&
+			    (!sk2->sk_bound_dev_if ||
+			     !sk->sk_bound_dev_if ||
+			     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 			    (!sk2->sk_reuse || !sk->sk_reuse) &&
 			    ipv6_rcv_saddr_equal(sk, sk2))
 				goto fail;