[PATCH] win32: ensure len does not cause any overreads

From: Rose via GitGitGadget <gitgitgadget@gmail.com>
Date: Dec 19, 2022, 17:17 UTC
Message-ID: <pull.1404.git.git.1671470222521.gitgitgadget@gmail.com>

From: Seija Kijin <doremylover123@gmail.com>

Check to make sure len is always less than MAX_PATH, otherwise an overread will occur, which is undefined behavior.

Signed-off-by: Seija Kijin <doremylover123@gmail.com>
---
    win32: ensure len does not cause any overreads
    
    Check to make sure len is always less than MAX_PATH, otherwise an
    overread will occur, which is undefined behavior.
    
    Signed-off-by: Seija Kijin doremylover123@gmail.com

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-git-1404%2FAtariDreams%2Foverread-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-git-1404/AtariDreams/overread-v1
Pull-Request: https://github.com/git/git/pull/1404

 compat/win32/dirent.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
index 52420ec7d4d..0c1bdccdd58 100644
--- a/compat/win32/dirent.c
+++ b/compat/win32/dirent.c
@@ -27,7 +27,7 @@ DIR *opendir(const char *name)
 	DIR *dir;
 
 	/* convert name to UTF-16 and check length < MAX_PATH */
-	if ((len = xutftowcs_path(pattern, name)) < 0)
+	if ((len = xutftowcs_path(pattern, name)) < 0 || len > MAX_PATH)
 		return NULL;
 
 	/* append optional '/' and wildcard '*' */

base-commit: 7c2ef319c52c4997256f5807564523dfd4acdfc7

-- 
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