https://github.com/python/cpython/commit/515a5d3498b572057056f0eef143a29838978705 commit: 515a5d3498b572057056f0eef143a29838978705 branch: 3.12 author: Kirill Podoprigora <kirill.ba...@mail.ru> committer: Eclips4 <kirill.ba...@mail.ru> date: 2024-10-29T20:20:40+02:00 summary:
[3.12] gh-126105: Fix crash in `ast` module, when `._fields` is delet… (#126132) [3.12] gh-126105: Fix crash in `ast` module, when `._fields` is deleted (GH-126115) Previously, if the `ast.AST._fields` attribute was deleted, attempts to create a new `as`t node would crash due to the assumption that `_fields` always had a non-NULL value. Now it has been fixed by adding an extra check to ensure that `_fields` does not have a NULL value (this can happen when you manually remove `_fields` attribute). (cherry picked from commit b2eaa75b176e07730215d76d8dce4d63fb493391) Co-authored-by: sobolevn <m...@sobolevn.me> files: A Misc/NEWS.d/next/Library/2024-10-29-11-45-44.gh-issue-126105.cOL-R6.rst M Lib/test/test_ast/test_ast.py M Parser/asdl_c.py M Python/Python-ast.c diff --git a/Lib/test/test_ast/test_ast.py b/Lib/test/test_ast/test_ast.py index 7510995b20e9d4..f07e2d027b1624 100644 --- a/Lib/test/test_ast/test_ast.py +++ b/Lib/test/test_ast/test_ast.py @@ -66,6 +66,23 @@ def test_AST_objects(self): # "ast.AST constructor takes 0 positional arguments" ast.AST(2) + def test_AST_fields_NULL_check(self): + # See: https://github.com/python/cpython/issues/126105 + old_value = ast.AST._fields + + def cleanup(): + ast.AST._fields = old_value + self.addCleanup(cleanup) + + del ast.AST._fields + + msg = "type object 'ast.AST' has no attribute '_fields'" + # Both examples used to crash: + with self.assertRaisesRegex(AttributeError, msg): + ast.AST(arg1=123) + with self.assertRaisesRegex(AttributeError, msg): + ast.AST() + def test_AST_garbage_collection(self): class X: pass diff --git a/Misc/NEWS.d/next/Library/2024-10-29-11-45-44.gh-issue-126105.cOL-R6.rst b/Misc/NEWS.d/next/Library/2024-10-29-11-45-44.gh-issue-126105.cOL-R6.rst new file mode 100644 index 00000000000000..547eb3af1ca064 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-10-29-11-45-44.gh-issue-126105.cOL-R6.rst @@ -0,0 +1 @@ +Fix a crash in :mod:`ast` when the :attr:`ast.AST._fields` attribute is deleted. diff --git a/Parser/asdl_c.py b/Parser/asdl_c.py index 2c34f5c1bc2675..6f5a772dccbd3f 100755 --- a/Parser/asdl_c.py +++ b/Parser/asdl_c.py @@ -813,14 +813,15 @@ def visitModule(self, mod): Py_ssize_t i, numfields = 0; int res = -1; PyObject *key, *value, *fields; - if (_PyObject_LookupAttr((PyObject*)Py_TYPE(self), state->_fields, &fields) < 0) { + + fields = PyObject_GetAttr((PyObject*)Py_TYPE(self), state->_fields); + if (fields == NULL) { goto cleanup; } - if (fields) { - numfields = PySequence_Size(fields); - if (numfields == -1) { - goto cleanup; - } + + numfields = PySequence_Size(fields); + if (numfields == -1) { + goto cleanup; } res = 0; /* if no error occurs, this stays 0 to the end */ diff --git a/Python/Python-ast.c b/Python/Python-ast.c index ecaff2041f9565..3d5aeff837953b 100644 --- a/Python/Python-ast.c +++ b/Python/Python-ast.c @@ -863,14 +863,15 @@ ast_type_init(PyObject *self, PyObject *args, PyObject *kw) Py_ssize_t i, numfields = 0; int res = -1; PyObject *key, *value, *fields; - if (_PyObject_LookupAttr((PyObject*)Py_TYPE(self), state->_fields, &fields) < 0) { + + fields = PyObject_GetAttr((PyObject*)Py_TYPE(self), state->_fields); + if (fields == NULL) { goto cleanup; } - if (fields) { - numfields = PySequence_Size(fields); - if (numfields == -1) { - goto cleanup; - } + + numfields = PySequence_Size(fields); + if (numfields == -1) { + goto cleanup; } res = 0; /* if no error occurs, this stays 0 to the end */ _______________________________________________ Python-checkins mailing list -- python-checkins@python.org To unsubscribe send an email to python-checkins-le...@python.org https://mail.python.org/mailman3/lists/python-checkins.python.org/ Member address: arch...@mail-archive.com