Bluetooth: hci_event: Fix enabling passive scanning

Passive scanning shall only be enabled when disconnecting LE links,
otherwise it may start result in triggering scanning when e.g. an ISO
link disconnects:

> HCI Event: LE Meta Event (0x3e) plen 29
      LE Connected Isochronous Stream Established (0x19)
        Status: Success (0x00)
        Connection Handle: 257
        CIG Synchronization Delay: 0 us (0x000000)
        CIS Synchronization Delay: 0 us (0x000000)
        Central to Peripheral Latency: 10000 us (0x002710)
        Peripheral to Central Latency: 10000 us (0x002710)
        Central to Peripheral PHY: LE 2M (0x02)
        Peripheral to Central PHY: LE 2M (0x02)
        Number of Subevents: 1
        Central to Peripheral Burst Number: 1
        Peripheral to Central Burst Number: 1
        Central to Peripheral Flush Timeout: 2
        Peripheral to Central Flush Timeout: 2
        Central to Peripheral MTU: 320
        Peripheral to Central MTU: 160
        ISO Interval: 10.00 msec (0x0008)
...
> HCI Event: Disconnect Complete (0x05) plen 4
        Status: Success (0x00)
        Handle: 257
        Reason: Remote User Terminated Connection (0x13)
< HCI Command: LE Set Extended Scan Enable (0x08|0x0042) plen 6
        Extended scan: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
        Duration: 0 msec (0x0000)
        Period: 0.00 sec (0x0000)

Fixes: 9fcb18e ("Bluetooth: Introduce LE auto connect options")
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: Vudentz

net/bluetooth/hci_event.c

@@ -3391,23 +3391,30 @@ static void hci_disconn_complete_evt(struct hci_dev *hdev, void *data,
 		hci_update_scan(hdev);
 	}
 
-	params = hci_conn_params_lookup(hdev, &conn->dst, conn->dst_type);
-	if (params) {
-		switch (params->auto_connect) {
-		case HCI_AUTO_CONN_LINK_LOSS:
-			if (ev->reason != HCI_ERROR_CONNECTION_TIMEOUT)
+	/* Re-enable passive scanning if disconnected device is marked
+	 * as auto-connectable.
+	 */
+	if (conn->type == LE_LINK) {
+		params = hci_conn_params_lookup(hdev, &conn->dst,
+						conn->dst_type);
+		if (params) {
+			switch (params->auto_connect) {
+			case HCI_AUTO_CONN_LINK_LOSS:
+				if (ev->reason != HCI_ERROR_CONNECTION_TIMEOUT)
+					break;
+				fallthrough;
+
+			case HCI_AUTO_CONN_DIRECT:
+			case HCI_AUTO_CONN_ALWAYS:
+				hci_pend_le_list_del_init(params);
+				hci_pend_le_list_add(params,
+						     &hdev->pend_le_conns);
+				hci_update_passive_scan(hdev);
 				break;
-			fallthrough;
 
-		case HCI_AUTO_CONN_DIRECT:
-		case HCI_AUTO_CONN_ALWAYS:
-			hci_pend_le_list_del_init(params);
-			hci_pend_le_list_add(params, &hdev->pend_le_conns);
-			hci_update_passive_scan(hdev);
-			break;
-
-		default:
-			break;
+			default:
+				break;
+			}
 		}
 	}