From fd83a823a6f268dc97ee2bf7d8a1a88d948446e5 Mon Sep 17 00:00:00 2001 From: Zackery Spytz Date: Wed, 3 Apr 2019 12:59:51 -0600 Subject: bpo-36504: Fix signed integer overflow in _ctypes.c's PyCArrayType_new(). (GH-12660) (GH-12678) (cherry picked from commit 487b73ab39c80157474821ef9083f51e0846bd62) --- Lib/ctypes/test/test_arrays.py | 6 ++++++ .../next/Core and Builtins/2019-04-02-04-10-32.bpo-36504.k_V8Bm.rst | 1 + Modules/_ctypes/_ctypes.c | 2 +- 3 files changed, 8 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2019-04-02-04-10-32.bpo-36504.k_V8Bm.rst diff --git a/Lib/ctypes/test/test_arrays.py b/Lib/ctypes/test/test_arrays.py index 53859a3..29fd422 100644 --- a/Lib/ctypes/test/test_arrays.py +++ b/Lib/ctypes/test/test_arrays.py @@ -134,6 +134,12 @@ class ArrayTestCase(unittest.TestCase): t2 = my_int * 1 self.assertIs(t1, t2) + def test_bpo36504_signed_int_overflow(self): + # The overflow check in PyCArrayType_new() could cause signed integer + # overflow. + with self.assertRaises(OverflowError): + c_char * sys.maxsize * 2 + @unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform') @precisionbigmemtest(size=_2G, memuse=1, dry_run=False) def test_large_array(self, size): diff --git a/Misc/NEWS.d/next/Core and Builtins/2019-04-02-04-10-32.bpo-36504.k_V8Bm.rst b/Misc/NEWS.d/next/Core and Builtins/2019-04-02-04-10-32.bpo-36504.k_V8Bm.rst new file mode 100644 index 0000000..8ac209d --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2019-04-02-04-10-32.bpo-36504.k_V8Bm.rst @@ -0,0 +1 @@ +Fix signed integer overflow in _ctypes.c's ``PyCArrayType_new()``. diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c index 33e2243..d608100 100644 --- a/Modules/_ctypes/_ctypes.c +++ b/Modules/_ctypes/_ctypes.c @@ -1534,7 +1534,7 @@ PyCArrayType_new(PyTypeObject *type, PyObject *args, PyObject *kwds) } itemsize = itemdict->size; - if (length * itemsize < 0) { + if (length > PY_SSIZE_T_MAX / itemsize) { PyErr_SetString(PyExc_OverflowError, "array too large"); Py_DECREF(stgdict); -- cgit v0.12