[Python-checkins] Fix possible refleak involving _PyArena_AddPyObject (GH-25289)

[pablogsal]

https://github.com/python/cpython/commit/c0e11a3ceb9427e09db4224f394c7789bf6deec5
commit: c0e11a3ceb9427e09db4224f394c7789bf6deec5
branch: master
author: Erlend Egeberg Aasland <erlend.aasland at innova.no>
committer: pablogsal <Pablogsal at gmail.com>
date: 2021-04-09T00:05:44+01:00
summary:

Fix possible refleak involving _PyArena_AddPyObject (GH-25289)

files:
M Parser/pegen.c

diff --git a/Parser/pegen.c b/Parser/pegen.c
index 82dcd3bb5a858..7b5a5e9146857 100644
--- a/Parser/pegen.c
+++ b/Parser/pegen.c
@@ -690,7 +690,10 @@ _PyPegen_fill_token(Parser *p)
     if (t->bytes == NULL) {
         return -1;
     }
-    _PyArena_AddPyObject(p->arena, t->bytes);
+    if (_PyArena_AddPyObject(p->arena, t->bytes) < 0) {
+        Py_DECREF(t->bytes);
+        return -1;
+    }
 
     int lineno = type == STRING ? p->tok->first_lineno : p->tok->lineno;
     const char *line_start = type == STRING ? p->tok->multi_line_start : p->tok->line_start;