[3.12] gh-129345: null check for indent syslogmodule (GH-129348) (#129443)

gh-129345: null check for indent syslogmodule (GH-129348)
(cherry picked from commit 25cf79a)

Co-authored-by: Burkov Egor <[email protected]>

Author: miss-islington

Misc/NEWS.d/next/Core_and_Builtins/2025-01-28-06-23-59.gh-issue-129345.uOjkML.rst

@@ -0,0 +1 @@
+Fix null pointer dereference in :func:`syslog.openlog` when an audit hook raises an exception.

Modules/syslogmodule.c

@@ -170,7 +170,7 @@ syslog_openlog_impl(PyObject *module, PyObject *ident, long logopt,
         }
     }
     if (PySys_Audit("syslog.openlog", "Oll", ident ? ident : Py_None, logopt, facility) < 0) {
-        Py_DECREF(ident);
+        Py_XDECREF(ident);
         return NULL;
     }