https://github.com/python/cpython/commit/96c9394c8a1b1ef67c1fbb09b8575a173a324b8f commit: 96c9394c8a1b1ef67c1fbb09b8575a173a324b8f branch: 3.14 author: Miss Islington (bot) <[email protected]> committer: encukou <[email protected]> date: 2026-03-03T12:48:05+01:00 summary:
[3.14] gh-142781: Fix type confusion in zoneinfo weak cache (GH-142925) (GH-145419) (cherry picked from commit b611db491d16ebbb4c833e9a184bb987e41f9fbe) Co-authored-by: zhong <[email protected]> Co-authored-by: Bénédikt Tran <[email protected]> Co-authored-by: Stan Ulbrych <[email protected]> files: A Misc/NEWS.d/next/Library/2025-12-18-00-14-16.gh-issue-142781.gcOeYF.rst M Lib/test/test_zoneinfo/test_zoneinfo.py M Modules/_zoneinfo.c diff --git a/Lib/test/test_zoneinfo/test_zoneinfo.py b/Lib/test/test_zoneinfo/test_zoneinfo.py index 88d79b258cdf7a..8a58c7d68acf82 100644 --- a/Lib/test/test_zoneinfo/test_zoneinfo.py +++ b/Lib/test/test_zoneinfo/test_zoneinfo.py @@ -1577,6 +1577,44 @@ class EvilZoneInfo(self.klass): class CZoneInfoCacheTest(ZoneInfoCacheTest): module = c_zoneinfo + def test_inconsistent_weak_cache_get(self): + class Cache: + def get(self, key, default=None): + return 1337 + + class ZI(self.klass): + pass + # Class attribute must be set after class creation + # to override zoneinfo.ZoneInfo.__init_subclass__. + ZI._weak_cache = Cache() + + with self.assertRaises(RuntimeError) as te: + ZI("America/Los_Angeles") + self.assertEqual( + str(te.exception), + "Unexpected instance of int in ZI weak cache for key 'America/Los_Angeles'" + ) + + def test_inconsistent_weak_cache_setdefault(self): + class Cache: + def get(self, key, default=None): + return default + def setdefault(self, key, value): + return 1337 + + class ZI(self.klass): + pass + # Class attribute must be set after class creation + # to override zoneinfo.ZoneInfo.__init_subclass__. + ZI._weak_cache = Cache() + + with self.assertRaises(RuntimeError) as te: + ZI("America/Los_Angeles") + self.assertEqual( + str(te.exception), + "Unexpected instance of int in ZI weak cache for key 'America/Los_Angeles'" + ) + class ZoneInfoPickleTest(TzPathUserMixin, ZoneInfoTestBase): module = py_zoneinfo diff --git a/Misc/NEWS.d/next/Library/2025-12-18-00-14-16.gh-issue-142781.gcOeYF.rst b/Misc/NEWS.d/next/Library/2025-12-18-00-14-16.gh-issue-142781.gcOeYF.rst new file mode 100644 index 00000000000000..772e05766c5c69 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2025-12-18-00-14-16.gh-issue-142781.gcOeYF.rst @@ -0,0 +1,2 @@ +:mod:`zoneinfo`: fix a crash when instantiating :class:`~zoneinfo.ZoneInfo` +objects for which the internal class-level cache is inconsistent. diff --git a/Modules/_zoneinfo.c b/Modules/_zoneinfo.c index bfb86bdbf1a3f7..25f7eb7a44d827 100644 --- a/Modules/_zoneinfo.c +++ b/Modules/_zoneinfo.c @@ -335,6 +335,7 @@ zoneinfo_ZoneInfo_impl(PyTypeObject *type, PyObject *key) return NULL; } + ((PyZoneInfo_ZoneInfo *)tmp)->source = SOURCE_CACHE; instance = PyObject_CallMethod(weak_cache, "setdefault", "OO", key, tmp); Py_DECREF(tmp); @@ -342,7 +343,15 @@ zoneinfo_ZoneInfo_impl(PyTypeObject *type, PyObject *key) Py_DECREF(weak_cache); return NULL; } - ((PyZoneInfo_ZoneInfo *)instance)->source = SOURCE_CACHE; + } + + if (!PyObject_TypeCheck(instance, type)) { + PyErr_Format(PyExc_RuntimeError, + "Unexpected instance of %T in %s weak cache for key %R", + instance, _PyType_Name(type), key); + Py_DECREF(instance); + Py_DECREF(weak_cache); + return NULL; } update_strong_cache(state, type, key, instance); _______________________________________________ Python-checkins mailing list -- [email protected] To unsubscribe send an email to [email protected] https://mail.python.org/mailman3//lists/python-checkins.python.org Member address: [email protected]
