From: Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com>
Date: Mon, 9 Sep 2019 14:23:37 +0000 (-0700)
Subject: bpo-32587: Fixes unsafe downcast in PC/winreg.c (GH-15766)
X-Git-Tag: v3.8.0rc1~257
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=44729c9f5198211faf533da49fa0fa26693a1993;p=python

bpo-32587: Fixes unsafe downcast in PC/winreg.c (GH-15766)

(cherry picked from commit ef66f31ce21cd759cc0c618c5c42ba6da0a06834)

Co-authored-by: Steve Dower <steve.dower@python.org>
---

diff --git a/PC/winreg.c b/PC/winreg.c
index 37bc2c72dc..72a7c380be 100644
--- a/PC/winreg.c
+++ b/PC/winreg.c
@@ -772,7 +772,7 @@ Reg2Py(BYTE *retDataBuf, DWORD retDataSize, DWORD typ)
                         return NULL;
                     }
                     PyList_SET_ITEM(obData, index, uni);
-                    len -= slen + 1;
+                    len -= Py_SAFE_DOWNCAST(slen + 1, size_t, int);
                 }
                 PyMem_Free(str);