[PATCH AUTOSEL 6.12 2/5] orangefs: fix a oob in orangefs_debug_write

Sasha Levin
2025-02-04T01:18:04Z

From: Mike Marshall <hubcap@omnibond.com>

[ 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>
---
fs/orangefs/orangefs-debugfs.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c
index 1b508f5433846..fa41db0884880 100644
--- a/fs/orangefs/orangefs-debugfs.c
+++ b/fs/orangefs/orangefs-debugfs.c
@@ -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);
--
2.39.5