[Python-checkins] bpo-31579: Fixed a possible leak in enumerate() with large indices. (#3753)

[Serhiy Storchaka]

https://github.com/python/cpython/commit/0e950dd22b075b4809c84afda8aede02b76ac0fa
commit: 0e950dd22b075b4809c84afda8aede02b76ac0fa
branch: master
author: Serhiy Storchaka <storchaka at gmail.com>
committer: GitHub <noreply at github.com>
date: 2017-09-26T08:14:58+03:00
summary:

bpo-31579: Fixed a possible leak in enumerate() with large indices. (#3753)

files:
M Objects/enumobject.c

diff --git a/Objects/enumobject.c b/Objects/enumobject.c
index 154d901e86d..4d0af14008b 100644
--- a/Objects/enumobject.c
+++ b/Objects/enumobject.c
@@ -108,14 +108,18 @@ enum_next_long(enumobject *en, PyObject* next_item)
 
     if (en->en_longindex == NULL) {
         en->en_longindex = PyLong_FromSsize_t(PY_SSIZE_T_MAX);
-        if (en->en_longindex == NULL)
+        if (en->en_longindex == NULL) {
+            Py_DECREF(next_item);
             return NULL;
+        }
     }
     next_index = en->en_longindex;
     assert(next_index != NULL);
     stepped_up = PyNumber_Add(next_index, _PyLong_One);
-    if (stepped_up == NULL)
+    if (stepped_up == NULL) {
+        Py_DECREF(next_item);
         return NULL;
+    }
     en->en_longindex = stepped_up;
 
     if (result->ob_refcnt == 1) {