--- x/net/core/sock_map.c
+++ y/net/core/sock_map.c
@@ -188,7 +188,7 @@ static void sock_map_unref(struct sock *
 
 static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock)
 {
-	if (!sk->sk_prot->psock_update_sk_prot)
+	if (!sk->sk_prot->psock_update_sk_prot || sk->sk_prot->close == sock_map_close)
 		return -EINVAL;
 	psock->psock_update_sk_prot = sk->sk_prot->psock_update_sk_prot;
 	return sk->sk_prot->psock_update_sk_prot(sk, psock, false);