Bluetooth: Check address length before reading address field

KMSAN will complain if valid address length passed to bind() is shorter
than sizeof(struct sockaddr_sco) bytes.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bluetooth/sco.c

@@ -523,12 +523,12 @@ static int sco_sock_bind(struct socket *sock, struct sockaddr *addr,
 	struct sock *sk = sock->sk;
 	int err = 0;
 
-	BT_DBG("sk %p %pMR", sk, &sa->sco_bdaddr);
-
 	if (!addr || addr_len < sizeof(struct sockaddr_sco) ||
 	    addr->sa_family != AF_BLUETOOTH)
 		return -EINVAL;
 
+	BT_DBG("sk %p %pMR", sk, &sa->sco_bdaddr);
+
 	lock_sock(sk);
 
 	if (sk->sk_state != BT_OPEN) {