pythonGH-93990: fix refcounting bug in add_subclass in `typeobject.…

…c` (pythonGH-93989) (cherry picked from commit 726448e) Co-authored-by: Kumar Aditya <[email protected]>
vstinner · Jun 19, 2022 · 15c8838 · 15c8838
1 parent 0c826d3
commit 15c8838
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
@@ -6512,8 +6512,11 @@ add_subclass(PyTypeObject *base, PyTypeObject *type)
     PyObject *subclasses = base->tp_subclasses;
     if (subclasses == NULL) {
         base->tp_subclasses = subclasses = PyDict_New();
-        if (subclasses == NULL)
+        if (subclasses == NULL) {
+            Py_DECREF(key);
+            Py_DECREF(ref);
             return -1;
+        }
     }
     assert(PyDict_CheckExact(subclasses));