Bluetooth: hci_conn: Use disable_delayed_work_sync

This makes use of disable_delayed_work_sync instead
cancel_delayed_work_sync as it not only cancel the ongoing work but also
disables new submit which is disarable since the object holding the work
is about to be freed.

Reported-by: [email protected]
Tested-by: [email protected]
Closes: https://syzkaller.appspot.com/bug?extid=2446dd3cb07277388db6
Signed-off-by: Luiz Augusto von Dentz <[email protected]>

Author: Vudentz

net/bluetooth/hci_conn.c

@@ -1127,9 +1127,9 @@ void hci_conn_del(struct hci_conn *conn)
 
 	hci_conn_unlink(conn);
 
-	cancel_delayed_work_sync(&conn->disc_work);
-	cancel_delayed_work_sync(&conn->auto_accept_work);
-	cancel_delayed_work_sync(&conn->idle_work);
+	disable_delayed_work_sync(&conn->disc_work);
+	disable_delayed_work_sync(&conn->auto_accept_work);
+	disable_delayed_work_sync(&conn->idle_work);
 
 	if (conn->type == ACL_LINK) {
 		/* Unacked frames */