Bluetooth: fix uninitialized variables notify_evt

Coverity Scan report:

[...]
*** CID 1493985:  Uninitialized variables  (UNINIT)
/net/bluetooth/hci_event.c: 4535 in hci_sync_conn_complete_evt()
4529
4530     	/* Notify only in case of SCO over HCI transport data path which
4531     	 * is zero and non-zero value shall be non-HCI transport data path
4532     	 */
4533     	if (conn->codec.data_path == 0) {
4534     		if (hdev->notify)
>>>     CID 1493985:  Uninitialized variables  (UNINIT)
>>>     Using uninitialized value "notify_evt" when calling "*hdev->notify".
4535     			hdev->notify(hdev, notify_evt);
4536     	}
4537
4538     	hci_connect_cfm(conn, ev->status);
4539     	if (ev->status)
4540     		hci_conn_del(conn);
[...]

Although only btusb uses air_mode, and he only handles HCI_NOTIFY_ENABLE_SCO_CVSD
and HCI_NOTIFY_ENABLE_SCO_TRANSP, there is still a very small chance that
ev->air_mode is not equal to 0x2 and 0x3, but notify_evt is initialized to
HCI_NOTIFY_ENABLE_SCO_CVSD or HCI_NOTIFY_ENABLE_SCO_TRANSP. the context is
maybe not correct.

Let us directly use the required function instead of re-initializing it,
so as to restore the original logic and make the code more correct.

Addresses-Coverity: ("Uninitialized variables")
Fixes: f4f9fa0c07bb ("Bluetooth: Allow usb to auto-suspend when SCO use	non-HCI transport")
Suggested-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 5471fbf388738f05764f2adc463ad48f4af21b5c..9e27ff343716318f9f4d5b6d517dc6c3fffbf000 100644 (file)
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -4530,7 +4530,6 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev,
 {
        struct hci_ev_sync_conn_complete *ev = (void *) skb->data;
        struct hci_conn *conn;
-       unsigned int notify_evt;
 
        BT_DBG("%s status 0x%2.2x", hdev->name, ev->status);
 
@@ -4602,22 +4601,18 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev,
        }
 
        bt_dev_dbg(hdev, "SCO connected with air mode: %02x", ev->air_mode);
-
-       switch (ev->air_mode) {
-       case 0x02:
-               notify_evt = HCI_NOTIFY_ENABLE_SCO_CVSD;
-               break;
-       case 0x03:
-               notify_evt = HCI_NOTIFY_ENABLE_SCO_TRANSP;
-               break;
-       }
-
        /* Notify only in case of SCO over HCI transport data path which
         * is zero and non-zero value shall be non-HCI transport data path
         */
-       if (conn->codec.data_path == 0) {
-               if (hdev->notify)
-                       hdev->notify(hdev, notify_evt);
+       if (conn->codec.data_path == 0 && hdev->notify) {
+               switch (ev->air_mode) {
+               case 0x02:
+                       hdev->notify(hdev, HCI_NOTIFY_ENABLE_SCO_CVSD);
+                       break;
+               case 0x03:
+                       hdev->notify(hdev, HCI_NOTIFY_ENABLE_SCO_TRANSP);
+                       break;
+               }
        }
 
        hci_connect_cfm(conn, ev->status);