orangefs: fix a oob in orangefs_debug_write

[ Upstream commit f7c848431632598ff9bce57a659db6af60d75b39 ]

I got a syzbot report: slab-out-of-bounds Read in
orangefs_debug_write... several people suggested fixes,
I tested Al Viro's suggestion and made this patch.

Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Reported-by: syzbot+fc519d7875f2d9186c1f@syzkaller.appspotmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Mike Marshall 2025-01-08 14:21:08 -05:00 committed by Greg Kroah-Hartman
parent b47002ed65
commit 1da2697307

View File

@ -393,9 +393,9 @@ static ssize_t orangefs_debug_write(struct file *file,
* Thwart users who try to jamb a ridiculous number
* of bytes into the debug file...
*/
if (count > ORANGEFS_MAX_DEBUG_STRING_LEN + 1) {
if (count > ORANGEFS_MAX_DEBUG_STRING_LEN) {
silly = count;
count = ORANGEFS_MAX_DEBUG_STRING_LEN + 1;
count = ORANGEFS_MAX_DEBUG_STRING_LEN;
}
buf = kzalloc(ORANGEFS_MAX_DEBUG_STRING_LEN, GFP_KERNEL);