af_iucv: Validate socket address length in iucv_sock_bind()

commit 52a82e23 upstream.
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Evgeny Cherkashin <Eugene.Crosser@ru.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

net/iucv/af_iucv.c

@@ -709,6 +709,9 @@ static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
 	if (!addr || addr->sa_family != AF_IUCV)
 		return -EINVAL;
 
+	if (addr_len < sizeof(struct sockaddr_iucv))
+		return -EINVAL;
+
 	lock_sock(sk);
 	if (sk->sk_state != IUCV_OPEN) {
 		err = -EBADFD;