diff options
| -rw-r--r-- | Misc/NEWS | 4 | ||||
| -rw-r--r-- | Objects/listobject.c | 6 |
2 files changed, 7 insertions, 3 deletions
@@ -10,6 +10,10 @@ What's New in Python 3.3 Alpha 1? Core and Builtins ----------------- +- Issue #12973: Fix overflow check that relied on undefined behaviour in + list_repeat. This bug caused test_list to fail with recent versions + of Clang. + - Issue #12904: os.utime, os.futimes, os.lutimes, and os.futimesat now write atime and mtime with nanosecond precision on modern POSIX platforms. diff --git a/Objects/listobject.c b/Objects/listobject.c index 2cd8642..cada708 100644 --- a/Objects/listobject.c +++ b/Objects/listobject.c @@ -58,7 +58,7 @@ list_resize(PyListObject *self, Py_ssize_t newsize) if (newsize == 0) new_allocated = 0; items = self->ob_item; - if (new_allocated <= ((~(size_t)0) / sizeof(PyObject *))) + if (new_allocated <= (PY_SIZE_MAX / sizeof(PyObject *))) PyMem_RESIZE(items, PyObject *, new_allocated); else items = NULL; @@ -510,9 +510,9 @@ list_repeat(PyListObject *a, Py_ssize_t n) PyObject *elem; if (n < 0) n = 0; - size = Py_SIZE(a) * n; - if (n && size/n != Py_SIZE(a)) + if (n > 0 && Py_SIZE(a) > PY_SSIZE_T_MAX / n) return PyErr_NoMemory(); + size = Py_SIZE(a) * n; if (size == 0) return PyList_New(0); np = (PyListObject *) PyList_New(size); |