diff options
| -rw-r--r-- | Lib/test/test_list.py | 5 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Core and Builtins/2020-01-25-23-51-17.bpo-39453.xCOkYk.rst | 2 | ||||
| -rw-r--r-- | Objects/listobject.c | 7 |
3 files changed, 13 insertions, 1 deletions
diff --git a/Lib/test/test_list.py b/Lib/test/test_list.py index 6e3c4c1..33a55f7 100644 --- a/Lib/test/test_list.py +++ b/Lib/test/test_list.py @@ -221,6 +221,11 @@ class ListTest(list_tests.CommonTest): with self.assertRaises(ValueError): lst.remove(lst) + # bpo-39453: list.__contains__ was not holding strong references + # to list elements while calling PyObject_RichCompareBool(). + lst = [X(), X()] + 3 in lst + if __name__ == "__main__": unittest.main() diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-01-25-23-51-17.bpo-39453.xCOkYk.rst b/Misc/NEWS.d/next/Core and Builtins/2020-01-25-23-51-17.bpo-39453.xCOkYk.rst new file mode 100644 index 0000000..8c2e49f --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2020-01-25-23-51-17.bpo-39453.xCOkYk.rst @@ -0,0 +1,2 @@ +Fixed a possible crash in :meth:`list.__contains__` when a list is changed +during comparing items. Patch by Dong-hee Na. diff --git a/Objects/listobject.c b/Objects/listobject.c index a4e90db..38055d5 100644 --- a/Objects/listobject.c +++ b/Objects/listobject.c @@ -445,11 +445,16 @@ list_length(PyListObject *a) static int list_contains(PyListObject *a, PyObject *el) { + PyObject *item; Py_ssize_t i; int cmp; - for (i = 0, cmp = 0 ; cmp == 0 && i < Py_SIZE(a); ++i) + for (i = 0, cmp = 0 ; cmp == 0 && i < Py_SIZE(a); ++i) { + item = PyList_GET_ITEM(a, i); + Py_INCREF(item); cmp = PyObject_RichCompareBool(PyList_GET_ITEM(a, i), el, Py_EQ); + Py_DECREF(item); + } return cmp; } |