[Python-checkins] closes bpo-38127: _ctypes: PyObject_IsSubclass() should be checked for failure. (GH-16011)

[Benjamin Peterson]

https://github.com/python/cpython/commit/ea683deccc505a78bbbb1eb8c6a88b0835ad5151
commit: ea683deccc505a78bbbb1eb8c6a88b0835ad5151
branch: master
author: Zackery Spytz <zspytz at gmail.com>
committer: Benjamin Peterson <benjamin at python.org>
date: 2019-09-12T11:09:32+01:00
summary:

closes bpo-38127: _ctypes: PyObject_IsSubclass() should be checked for failure. (GH-16011)

An exception may occur during a PyObject_IsSubclass() call.

files:
M Modules/_ctypes/_ctypes.c

diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index d2f6391fa6db..16a0cfe8dd4d 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -1168,7 +1168,11 @@ PyCPointerType_from_param(PyObject *type, PyObject *value)
         */
         StgDictObject *v = PyObject_stgdict(value);
         assert(v); /* Cannot be NULL for pointer or array objects */
-        if (PyObject_IsSubclass(v->proto, typedict->proto)) {
+        int ret = PyObject_IsSubclass(v->proto, typedict->proto);
+        if (ret < 0) {
+            return NULL;
+        }
+        if (ret) {
             Py_INCREF(value);
             return value;
         }