Fix the overflow checking of list_repeat.
Introduce overflow checking into list_inplace_repeat.
Backport candidate, possibly.
diff --git a/Lib/test/test_list.py b/Lib/test/test_list.py
index 711ac4b..3489529 100644
--- a/Lib/test/test_list.py
+++ b/Lib/test/test_list.py
@@ -1,4 +1,5 @@
import unittest
+import sys
from test import test_support, list_tests
class ListTest(list_tests.CommonTest):
@@ -18,6 +19,14 @@
self.assertEqual(len([0]), 1)
self.assertEqual(len([0, 1, 2]), 3)
+ def test_overflow(self):
+ lst = [4, 5, 6, 7]
+ n = int((sys.maxint*2+2) // len(lst))
+ def mul(a, b): return a * b
+ def imul(a, b): a *= b
+ self.assertRaises((MemoryError, OverflowError), mul, lst, n)
+ self.assertRaises((MemoryError, OverflowError), imul, lst, n)
+
def test_main(verbose=None):
test_support.run_unittest(ListTest)
diff --git a/Objects/listobject.c b/Objects/listobject.c
index a3fa983..fb5ce82 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -499,10 +499,10 @@
if (n < 0)
n = 0;
size = Py_Size(a) * n;
- if (size == 0)
- return PyList_New(0);
if (n && size/n != Py_Size(a))
return PyErr_NoMemory();
+ if (size == 0)
+ return PyList_New(0);
np = (PyListObject *) PyList_New(size);
if (np == NULL)
return NULL;
@@ -669,7 +669,7 @@
list_inplace_repeat(PyListObject *self, Py_ssize_t n)
{
PyObject **items;
- Py_ssize_t size, i, j, p;
+ Py_ssize_t size, i, j, p, newsize;
size = PyList_GET_SIZE(self);
@@ -684,7 +684,10 @@
return (PyObject *)self;
}
- if (list_resize(self, size*n) == -1)
+ newsize = size * n;
+ if (newsize/n != size)
+ return PyErr_NoMemory();
+ if (list_resize(self, newsize) == -1)
return NULL;
p = size;