[Bluetooth] Use a more unique bus name for connections

When attaching Bluetooth low-level connections to the bus, the bus name
is constructed from the remote address since at that time the connection
handle is not assigned yet. This has worked so far, but also caused a
lot of troubles. It is better to postpone the creation of the sysfs
entry to the time when the connection actually has been established
and then use its connection handle as unique identifier.

This also fixes the case where two different adapters try to connect
to the same remote device.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/bluetooth/hci_conn.c

@@ -245,8 +245,6 @@ struct hci_conn *hci_conn_add(struct hci_dev *hdev, int type, bdaddr_t *dst)
 	if (hdev->notify)
 		hdev->notify(hdev, HCI_NOTIFY_CONN_ADD);
 
-	hci_conn_add_sysfs(conn);
-
 	tasklet_enable(&hdev->tx_task);
 
 	return conn;
@@ -278,12 +276,14 @@ int hci_conn_del(struct hci_conn *conn)
 	}
 
 	tasklet_disable(&hdev->tx_task);
+
 	hci_conn_hash_del(hdev, conn);
 	if (hdev->notify)
 		hdev->notify(hdev, HCI_NOTIFY_CONN_DEL);
+
 	tasklet_enable(&hdev->tx_task);
+
 	skb_queue_purge(&conn->data_q);
-	hci_conn_del_sysfs(conn);
 
 	return 0;
 }
@@ -532,6 +532,8 @@ void hci_conn_hash_flush(struct hci_dev *hdev)
 
 		c->state = BT_CLOSED;
 
+		hci_conn_del_sysfs(c);
+
 		hci_proto_disconn_ind(c, 0x16);
 		hci_conn_del(c);
 	}