Bluetooth: Allow only one LE connection attempt

Only one outgoing LE connection attempt should be possible.
hci_connect() will now return -EBUSY in case there's another pending
outgoing connection.
Signed-off-by: NAndrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: NGustavo Padovan <gustavo.padovan@collabora.co.uk>

net/bluetooth/hci_conn.c

@@ -483,6 +483,11 @@ struct hci_conn *hci_connect(struct hci_dev *hdev, int type, bdaddr_t *dst,
 	if (type == LE_LINK) {
 		le = hci_conn_hash_lookup_ba(hdev, LE_LINK, dst);
 		if (!le) {
+			le = hci_conn_hash_lookup_state(hdev, LE_LINK,
+							BT_CONNECT);
+			if (le)
+				return ERR_PTR(-EBUSY);
+
 			le = hci_conn_add(hdev, LE_LINK, dst);
 			if (!le)
 				return ERR_PTR(-ENOMEM);