bpo-40998: Fix a refleak in create_filter() (GH-23365)

vstinner · web-flow · commit d1e38d4023aa · 2020-11-18T06:57:10.000-08:00
diff --git a/Python/_warnings.c b/Python/_warnings.c
@@ -69,12 +69,14 @@ create_filter(PyObject *category, _Py_Identifier *id, const char *modname)
             return NULL;
         }
     } else {
-        modname_obj = Py_None;
+        modname_obj = Py_NewRef(Py_None);
     }
 
     /* This assumes the line number is zero for now. */
-    return PyTuple_Pack(5, action_str, Py_None,
-                        category, modname_obj, _PyLong_GetZero());
+    PyObject *filter = PyTuple_Pack(5, action_str, Py_None,
+                                    category, modname_obj, _PyLong_GetZero());
+    Py_DECREF(modname_obj);
+    return filter;
 }
 #endif
 

Original file line number	Diff line number	Diff line change
`@@ -69,12 +69,14 @@ create_filter(PyObject category, _Py_Identifier id, const char *modname)`
`69`	`69`	`return NULL;`
`70`	`70`	`}`
`71`	`71`	`} else {`
`72`		`- modname_obj = Py_None;`
	`72`	`+ modname_obj = Py_NewRef(Py_None);`
`73`	`73`	`}`
`74`	`74`
`75`	`75`	`/* This assumes the line number is zero for now. */`
`76`		`- return PyTuple_Pack(5, action_str, Py_None,`
`77`		`- category, modname_obj, _PyLong_GetZero());`
	`76`	`+ PyObject *filter = PyTuple_Pack(5, action_str, Py_None,`
	`77`	`+ category, modname_obj, _PyLong_GetZero());`
	`78`	`+ Py_DECREF(modname_obj);`
	`79`	`+ return filter;`
`78`	`80`	`}`
`79`	`81`	`#endif`
`80`	`82`