Bluetooth: hidp_connection_add() unsafe use of l2cap_pi()

it's OK after we'd verified the sockets, but not before that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/hidp/core.c

@@ -1314,13 +1314,14 @@ int hidp_connection_add(struct hidp_connadd_req *req,
 {
 	struct hidp_session *session;
 	struct l2cap_conn *conn;
-	struct l2cap_chan *chan = l2cap_pi(ctrl_sock->sk)->chan;
+	struct l2cap_chan *chan;
 	int ret;
 
 	ret = hidp_verify_sockets(ctrl_sock, intr_sock);
 	if (ret)
 		return ret;
 
+	chan = l2cap_pi(ctrl_sock->sk)->chan;
 	conn = NULL;
 	l2cap_chan_lock(chan);
 	if (chan->conn)