https://github.com/python/cpython/commit/e44045924da39169ee4ef38ae0211d58683... commit: e44045924da39169ee4ef38ae0211d586836cad4 branch: 3.12 author: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> committer: Eclips4 <kirill.bast9@mail.ru> date: 2025-01-03T21:21:08+02:00 summary: [3.12] gh-127903: Fix a crash on debug builds when calling `Objects/unicodeobject::_copy_characters` (GH-127876) (#128459) gh-127903: Fix a crash on debug builds when calling `Objects/unicodeobject::_copy_characters`` (GH-127876) (cherry picked from commit 46cb6340d7bad955edfc0a20f6a52dabc03b0932) Co-authored-by: Alexander Shadchin <shadchin@yandex-team.com> files: A Misc/NEWS.d/next/Core_and_Builtins/2024-12-13-14-17-24.gh-issue-127903.vemHSl.rst M Lib/test/test_unicode.py M Objects/unicodeobject.c diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py index 19556eecc3c646..a24acb7af2ff96 100644 --- a/Lib/test/test_unicode.py +++ b/Lib/test/test_unicode.py @@ -7,6 +7,7 @@ """ import _string import codecs +import datetime import itertools import operator import pickle @@ -1921,6 +1922,12 @@ def test_utf8_decode_invalid_sequences(self): self.assertRaises(UnicodeDecodeError, (b'\xF4'+cb+b'\xBF\xBF').decode, 'utf-8') + def test_issue127903(self): + # gh-127903: ``_copy_characters`` crashes on DEBUG builds when + # there is nothing to copy. + d = datetime.datetime(2013, 11, 10, 14, 20, 59) + self.assertEqual(d.strftime('%z'), '') + def test_issue8271(self): # Issue #8271: during the decoding of an invalid UTF-8 byte sequence, # only the start byte and the continuation byte(s) are now considered diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2024-12-13-14-17-24.gh-issue-127903.vemHSl.rst b/Misc/NEWS.d/next/Core_and_Builtins/2024-12-13-14-17-24.gh-issue-127903.vemHSl.rst new file mode 100644 index 00000000000000..ad479b52d1675c --- /dev/null +++ b/Misc/NEWS.d/next/Core_and_Builtins/2024-12-13-14-17-24.gh-issue-127903.vemHSl.rst @@ -0,0 +1,2 @@ +``Objects/unicodeobject.c``: fix a crash on DEBUG builds in ``_copy_characters`` +when there is nothing to copy. diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index c885be5b6682aa..3e5b5d03241ae0 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -1472,11 +1472,14 @@ _copy_characters(PyObject *to, Py_ssize_t to_start, assert(PyUnicode_Check(from)); assert(from_start + how_many <= PyUnicode_GET_LENGTH(from)); - assert(PyUnicode_Check(to)); - assert(to_start + how_many <= PyUnicode_GET_LENGTH(to)); + assert(to == NULL || PyUnicode_Check(to)); - if (how_many == 0) + if (how_many == 0) { return 0; + } + + assert(to != NULL); + assert(to_start + how_many <= PyUnicode_GET_LENGTH(to)); from_kind = PyUnicode_KIND(from); from_data = PyUnicode_DATA(from);