Issue #15989: Fix several occurrences of integer overflow

when result of PyLong_AsLong() narrowed to int without checks.

This is a backport of changesets 13e2e44db99d and 525407d89277.

1 files changed, 9 insertions, 0 deletions

diff --git a/Lib/ctypes/test/test_structures.py b/Lib/ctypes/test/test_structures.py
index b6d8b01..d764ce2 100644
--- a/Lib/ctypes/test/test_structures.py
+++ b/Lib/ctypes/test/test_structures.py
@@ -1,6 +1,7 @@
 import unittest
 from ctypes import *
 from struct import calcsize
+import _testcapi
 
 class SubclassesTest(unittest.TestCase):
     def test_subclass(self):
@@ -199,6 +200,14 @@ class StructureTestCase(unittest.TestCase):
              "_pack_": -1}
         self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)
 
+        # Issue 15989
+        d = {"_fields_": [("a", c_byte)],
+             "_pack_": _testcapi.INT_MAX + 1}
+        self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)
+        d = {"_fields_": [("a", c_byte)],
+             "_pack_": _testcapi.UINT_MAX + 2}
+        self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)
+
     def test_initializers(self):
         class Person(Structure):
             _fields_ = [("name", c_char*6),