Issues python#23363, python#23364, python#23365, python#23366: Fixed itertools overflow tests.

Used PyMem_New to check overflow.

Author: serhiy-storchaka

Lib/test/test_itertools.py

@@ -260,7 +260,7 @@ def combinations3(iterable, r):
 
     @support.bigaddrspacetest
     def test_combinations_overflow(self):
-        with self.assertRaises(OverflowError):
+        with self.assertRaises((OverflowError, MemoryError)):
             combinations("AA", 2**29)
 
         # Test implementation detail:  tuple re-use
@@ -346,7 +346,7 @@ def numcombs(n, r):
 
     @support.bigaddrspacetest
     def test_combinations_with_replacement_overflow(self):
-        with self.assertRaises(OverflowError):
+        with self.assertRaises((OverflowError, MemoryError)):
             combinations_with_replacement("AA", 2**30)
 
         # Test implementation detail:  tuple re-use
@@ -420,10 +420,8 @@ def permutations2(iterable, r=None):
 
     @support.bigaddrspacetest
     def test_permutations_overflow(self):
-        with self.assertRaises(OverflowError):
+        with self.assertRaises((OverflowError, MemoryError)):
             permutations("A", 2**30)
-        with self.assertRaises(OverflowError):
-            permutations("A", 2, 2**30)
 
     @support.impl_detail("tuple resuse is CPython specific")
     def test_permutations_tuple_reuse(self):
@@ -939,8 +937,8 @@ def product2(*args, **kwds):
 
     @support.bigaddrspacetest
     def test_product_overflow(self):
-        with self.assertRaises(OverflowError):
-            product(["a"]*(2**16), repeat=2**16)
+        with self.assertRaises((OverflowError, MemoryError)):
+            product(*(['ab']*2**5), repeat=2**25)
 
     @support.impl_detail("tuple reuse is specific to CPython")
     def test_product_tuple_reuse(self):

Modules/itertoolsmodule.c

@@ -2003,15 +2003,14 @@ product_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
         nargs = 0;
     } else {
         nargs = PyTuple_GET_SIZE(args);
-        if (repeat > PY_SSIZE_T_MAX/sizeof(Py_ssize_t) ||
-            nargs > PY_SSIZE_T_MAX/(repeat * sizeof(Py_ssize_t))) {
+        if ((size_t)nargs > PY_SSIZE_T_MAX/sizeof(Py_ssize_t)/repeat) {
             PyErr_SetString(PyExc_OverflowError, "repeat argument too large");
             return NULL;
         }
     }
     npools = nargs * repeat;
 
-    indices = PyMem_Malloc(npools * sizeof(Py_ssize_t));
+    indices = PyMem_New(Py_ssize_t, npools);
     if (indices == NULL) {
         PyErr_NoMemory();
         goto error;
@@ -2335,11 +2334,7 @@ combinations_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
         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));
+    indices = PyMem_New(Py_ssize_t, r);
     if (indices == NULL) {
         PyErr_NoMemory();
         goto error;
@@ -2668,11 +2663,7 @@ cwr_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
         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));
+    indices = PyMem_New(Py_ssize_t, r);
     if (indices == NULL) {
         PyErr_NoMemory();
         goto error;
@@ -3001,13 +2992,8 @@ permutations_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
         goto error;
     }
 
-    if (n > PY_SSIZE_T_MAX/sizeof(Py_ssize_t) ||
-        r > PY_SSIZE_T_MAX/sizeof(Py_ssize_t)) {
-        PyErr_SetString(PyExc_OverflowError, "parameters too large");
-        goto error;
-    }
-    indices = PyMem_Malloc(n * sizeof(Py_ssize_t));
-    cycles = PyMem_Malloc(r * sizeof(Py_ssize_t));
+    indices = PyMem_New(Py_ssize_t, n);
+    cycles = PyMem_New(Py_ssize_t, r);
     if (indices == NULL || cycles == NULL) {
         PyErr_NoMemory();
         goto error;