From: Tim Peters <tim.peters@gmail.com>
Date: Fri, 6 May 2022 04:14:09 +0000 (-0500)
Subject: Issues/88027: A potential double free in list_sort_impl (#92367)
X-Git-Tag: v3.11.0b1~22
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9652900969df77b1ac245595419431df19296af9;p=thirdparty%2FPython%2Fcpython.git

Issues/88027: A potential double free in list_sort_impl (#92367)

merge_freemem(): set keys to NULL do it's harmless to call this again.
---

diff --git a/Objects/listobject.c b/Objects/listobject.c
index 972f99582163..b50623ed73d9 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -1573,8 +1573,10 @@ static void
 merge_freemem(MergeState *ms)
 {
     assert(ms != NULL);
-    if (ms->a.keys != ms->temparray)
+    if (ms->a.keys != ms->temparray) {
         PyMem_Free(ms->a.keys);
+        ms->a.keys = NULL;
+    }
 }
 
 /* Ensure enough temp memory for 'need' array slots is available.