bpo-31544: Fix a reference leak to 'self' after the previous target error handling fixes. (GH-6318)
This change generally splits the xmlparser creation code into an unsafe part with "rollback" error handling and a safe "object initialisation done" part with normal decref cleanup.
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index 7f0e609..1d316a1 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -2575,14 +2575,24 @@
return NULL;
}
+ ALLOC(sizeof(XMLParserObject), "create expatparser");
+
+ /* Init to NULL to keep the error handling below manageable. */
+ self->target =
+ self->handle_xml =
+ self->handle_start =
+ self->handle_data =
+ self->handle_end =
+ self->handle_comment =
+ self->handle_pi =
+ self->handle_close =
+ NULL;
+
/* setup target handlers */
if (!target) {
target = treebuilder_new();
if (!target) {
- EXPAT(ParserFree)(self->parser);
- PyObject_Del(self->names);
- PyObject_Del(self->entity);
- PyObject_Del(self);
+ Py_DECREF(self);
return NULL;
}
} else
@@ -2591,30 +2601,37 @@
self->handle_xml = PyObject_GetAttrString(target, "xml");
if (ignore_attribute_error(self->handle_xml)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_start = PyObject_GetAttrString(target, "start");
if (ignore_attribute_error(self->handle_start)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_data = PyObject_GetAttrString(target, "data");
if (ignore_attribute_error(self->handle_data)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_end = PyObject_GetAttrString(target, "end");
if (ignore_attribute_error(self->handle_end)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_comment = PyObject_GetAttrString(target, "comment");
if (ignore_attribute_error(self->handle_comment)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_pi = PyObject_GetAttrString(target, "pi");
if (ignore_attribute_error(self->handle_pi)) {
+ Py_DECREF(self);
return NULL;
}
self->handle_close = PyObject_GetAttrString(target, "close");
if (ignore_attribute_error(self->handle_close)) {
+ Py_DECREF(self);
return NULL;
}
@@ -2650,8 +2667,6 @@
);
#endif
- ALLOC(sizeof(XMLParserObject), "create expatparser");
-
return (PyObject*) self;
}