af_iucv: Validate socket address length in iucv_sock_bind()

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>
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index ef50a94..fc3598a 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -708,6 +708,9 @@
 	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;