diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 7b4ce3f9e2f4..5ec73cf386df 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -718,6 +718,7 @@ static void tcp_v6_init_req(struct request_sock *req,
 			    const struct sock *sk_listener,
 			    struct sk_buff *skb)
 {
+	bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags);
 	struct inet_request_sock *ireq = inet_rsk(req);
 	const struct ipv6_pinfo *np = inet6_sk(sk_listener);
 
@@ -725,7 +726,7 @@ static void tcp_v6_init_req(struct request_sock *req,
 	ireq->ir_v6_loc_addr = ipv6_hdr(skb)->daddr;
 
 	/* So that link locals have meaning */
-	if (!sk_listener->sk_bound_dev_if &&
+	if ((!sk_listener->sk_bound_dev_if || l3_slave) &&
 	    ipv6_addr_type(&ireq->ir_v6_rmt_addr) & IPV6_ADDR_LINKLOCAL)
 		ireq->ir_iif = tcp_v6_iif(skb);