Add PYTHONMALLOC env var
Issue #26516:
* Add PYTHONMALLOC environment variable to set the Python memory
allocators and/or install debug hooks.
* PyMem_SetupDebugHooks() can now also be used on Python compiled in release
mode.
* The PYTHONMALLOCSTATS environment variable can now also be used on Python
compiled in release mode. It now has no effect if set to an empty string.
* In debug mode, debug hooks are now also installed on Python memory allocators
when Python is configured without pymalloc.
diff --git a/Lib/test/test_capi.py b/Lib/test/test_capi.py
index 74ec6c5..d56d702 100644
--- a/Lib/test/test_capi.py
+++ b/Lib/test/test_capi.py
@@ -6,6 +6,7 @@
import random
import subprocess
import sys
+import sysconfig
import textwrap
import time
import unittest
@@ -521,6 +522,7 @@
self.assertRaises(ValueError, _testcapi.parse_tuple_and_keywords,
(), {}, b'', [42])
+
@unittest.skipUnless(threading, 'Threading required for this test.')
class TestThreadState(unittest.TestCase):
@@ -545,6 +547,7 @@
t.start()
t.join()
+
class Test_testcapi(unittest.TestCase):
def test__testcapi(self):
for name in dir(_testcapi):
@@ -553,5 +556,61 @@
test = getattr(_testcapi, name)
test()
+
+class MallocTests(unittest.TestCase):
+ ENV = 'debug'
+
+ def check(self, code):
+ with support.SuppressCrashReport():
+ out = assert_python_failure('-c', code, PYTHONMALLOC=self.ENV)
+ stderr = out.err
+ return stderr.decode('ascii', 'replace')
+
+ def test_buffer_overflow(self):
+ out = self.check('import _testcapi; _testcapi.pymem_buffer_overflow()')
+ regex = (r"Debug memory block at address p=0x[0-9a-f]+: API 'm'\n"
+ r" 16 bytes originally requested\n"
+ r" The 7 pad bytes at p-7 are FORBIDDENBYTE, as expected.\n"
+ r" The 8 pad bytes at tail=0x[0-9a-f]+ are not all FORBIDDENBYTE \(0x[0-9a-f]{2}\):\n"
+ r" at tail\+0: 0x78 \*\*\* OUCH\n"
+ r" at tail\+1: 0xfb\n"
+ r" at tail\+2: 0xfb\n"
+ r" at tail\+3: 0xfb\n"
+ r" at tail\+4: 0xfb\n"
+ r" at tail\+5: 0xfb\n"
+ r" at tail\+6: 0xfb\n"
+ r" at tail\+7: 0xfb\n"
+ r" The block was made by call #[0-9]+ to debug malloc/realloc.\n"
+ r" Data at p: cb cb cb cb cb cb cb cb cb cb cb cb cb cb cb cb\n"
+ r"Fatal Python error: bad trailing pad byte")
+ self.assertRegex(out, regex)
+
+ def test_api_misuse(self):
+ out = self.check('import _testcapi; _testcapi.pymem_api_misuse()')
+ regex = (r"Debug memory block at address p=0x[0-9a-f]+: API 'm'\n"
+ r" 16 bytes originally requested\n"
+ r" The 7 pad bytes at p-7 are FORBIDDENBYTE, as expected.\n"
+ r" The 8 pad bytes at tail=0x[0-9a-f]+ are FORBIDDENBYTE, as expected.\n"
+ r" The block was made by call #[0-9]+ to debug malloc/realloc.\n"
+ r" Data at p: .*\n"
+ r"Fatal Python error: bad ID: Allocated using API 'm', verified using API 'r'\n")
+ self.assertRegex(out, regex)
+
+
+class MallocDebugTests(MallocTests):
+ ENV = 'malloc_debug'
+
+
+@unittest.skipUnless(sysconfig.get_config_var('WITH_PYMALLOC') == 1,
+ 'need pymalloc')
+class PymallocDebugTests(MallocTests):
+ ENV = 'pymalloc_debug'
+
+
+@unittest.skipUnless(Py_DEBUG, 'need Py_DEBUG')
+class DefaultMallocDebugTests(MallocTests):
+ ENV = ''
+
+
if __name__ == "__main__":
unittest.main()