pythongh-105979: Fix exception handling in unmarshal_frozen_code (Python/import.c) (python#105980)

Author: chgnrdv

Lib/test/test_import/__init__.py

@@ -23,6 +23,7 @@
 import unittest
 from unittest import mock
 import _testinternalcapi
+import _imp
 
 from test.support import os_helper
 from test.support import (
@@ -763,6 +764,13 @@ def test_dll_dependency_import(self):
  env=env,
  cwd=os.path.dirname(pyexe))
 
+ def test_issue105979(self):
+ # this used to crash
+ with self.assertRaises(ImportError) as cm:
+ _imp.get_frozen_object("x", b"6\'\xd5Cu\x12")
+ self.assertIn("Frozen object named 'x' is invalid",
+ str(cm.exception))
+
 
 @skip_if_dont_write_bytecode
 class FilePermissionTests(unittest.TestCase):

Misc/NEWS.d/next/Core and Builtins/2023-06-22-19-16-24.gh-issue-105979.TDP2CU.rst

@@ -0,0 +1 @@
+Fix crash in :func:`!_imp.get_frozen_object` due to improper exception handling.

Python/import.c

@@ -2071,6 +2071,7 @@ unmarshal_frozen_code(PyInterpreterState *interp, struct frozen_info *info)
  PyObject *co = PyMarshal_ReadObjectFromString(info->data, info->size);
  if (co == NULL) {
  /* Does not contain executable code. */
+ PyErr_Clear();
  set_frozen_error(FROZEN_INVALID, info->nameobj);
  return NULL;
  }