From: Johannes Schindelin <johannes.schindelin@gmx.de>
Date: Thu, 4 Jul 2019 22:36:57 +0000 (-0700)
Subject: mingw: fix possible buffer overrun when calling `GetUserNameW()`
X-Git-Tag: v2.23.0-rc0~43^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=697bdd22b887a0778489814e44dcec850aa82ad0;p=thirdparty%2Fgit.git

mingw: fix possible buffer overrun when calling `GetUserNameW()`

In 39a98e9b68b8 (mingw: get pw_name in UTF-8 format, 2019-06-27), this
developer missed the fact that the `GetUserNameW()` function takes the
number of characters as `len` parameter, not the number of bytes.

Reported-by: Beat Bolli <dev+git@drbeat.li>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---

diff --git a/compat/mingw.c b/compat/mingw.c
index b8a62bf914..a0eb695653 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c
@@ -1952,7 +1952,7 @@ struct passwd *getpwuid(int uid)
 	if (initialized)
 		return p;
 
-	len = sizeof(buf);
+	len = ARRAY_SIZE(buf);
 	if (!GetUserNameW(buf, &len)) {
 		initialized = 1;
 		return NULL;