s4/messaging/py: don't DECREF borrowed references

This made Message.deregister() a decref machine, with talloc crashes
and segfaults available thus:

    from samba import messaging
    m = messaging.Messaging()
    for i in range(20):
        m.deregister(m)

Signed-off-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Noel Power <npower@samba.org>

diff --git a/source4/lib/messaging/pymessaging.c b/source4/lib/messaging/pymessaging.c
index 39c09a8240324c5f4c73b08d1f340ed325df6416..e506d94f4742ecb2b5c6896842865f7ca24d19f5 100644 (file)
--- a/source4/lib/messaging/pymessaging.c
+++ b/source4/lib/messaging/pymessaging.c
@@ -259,8 +259,6 @@ static PyObject *py_imessaging_deregister(PyObject *self, PyObject *args, PyObje
 
        imessaging_deregister(iface->msg_ctx, msg_type, callback);
 
-       Py_DECREF(callback);
-
        Py_RETURN_NONE;
 }