detect overflow in combinations (closes #23366)
diff --git a/Lib/test/test_itertools.py b/Lib/test/test_itertools.py
index e5225f2..cbb1b92 100644
--- a/Lib/test/test_itertools.py
+++ b/Lib/test/test_itertools.py
@@ -137,6 +137,11 @@
self.assertEqual(result, list(combinations2(values, r))) # matches second pure python version
self.assertEqual(result, list(combinations3(values, r))) # matches second pure python version
+ @test_support.bigaddrspacetest
+ def test_combinations_overflow(self):
+ with self.assertRaises(OverflowError):
+ combinations("AA", 2**29)
+
@test_support.impl_detail("tuple reuse is specific to CPython")
def test_combinations_tuple_reuse(self):
self.assertEqual(len(set(map(id, combinations('abcde', 3)))), 1)
diff --git a/Misc/NEWS b/Misc/NEWS
index b4a52d2..87a1d9f 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -18,6 +18,8 @@
Library
-------
+- Issue #23366: Fixed possible integer overflow in itertools.combinations.
+
- Issue #23191: fnmatch functions that use caching are now threadsafe.
- Issue #18518: timeit now rejects statements which can't be compiled outside
diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index cd45eb9..4eab79c 100644
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -2093,6 +2093,10 @@
goto error;
}
+ if (r > PY_SSIZE_T_MAX/sizeof(Py_ssize_t)) {
+ PyErr_SetString(PyExc_OverflowError, "r is too big");
+ goto error;
+ }
indices = PyMem_Malloc(r * sizeof(Py_ssize_t));
if (indices == NULL) {
PyErr_NoMemory();