From: Alexey Izbyshev <izbyshev@users.noreply.github.com>
Date: Sun, 18 Feb 2018 17:57:24 +0000 (+0300)
Subject: bpo-32869: Fix incorrect dst buffer size for MultiByteToWideChar (#5739)
X-Git-Tag: v3.8.0a1~2207
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b3b4a9d3001f1fc7df8efcccdce081de54fa5eab;p=thirdparty%2FPython%2Fcpython.git

bpo-32869: Fix incorrect dst buffer size for MultiByteToWideChar (#5739)

This function expects the destination buffer size to be given
in wide characters, not bytes.
---

diff --git a/Python/fileutils.c b/Python/fileutils.c
index 3cf8b7a8b69d..32aeea4f1037 100644
--- a/Python/fileutils.c
+++ b/Python/fileutils.c
@@ -1289,7 +1289,8 @@ _Py_fopen_obj(PyObject *path, const char *mode)
     if (wpath == NULL)
         return NULL;
 
-    usize = MultiByteToWideChar(CP_ACP, 0, mode, -1, wmode, sizeof(wmode));
+    usize = MultiByteToWideChar(CP_ACP, 0, mode, -1,
+                                wmode, Py_ARRAY_LENGTH(wmode));
     if (usize == 0) {
         PyErr_SetFromWindowsErr(0);
         return NULL;