[PATCH 6.4 097/800] reiserfs: Initialize sec->length in reiserfs_security_init().

Greg Kroah-Hartman
2023-07-16T19:57:19Z

From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

[ Upstream commit d031f4e8b493df299123fbb4ec13db870584ed28 ]

syzbot is reporting that sec->length is not initialized.

Since security_inode_init_security() returns 0 when initxattrs is provided
but call_int_hook(inode_init_security) returned -EOPNOTSUPP, control will
reach to "if (sec->length && ...) {" without initializing sec->length.

Reported-by: syzbot <syzbot+00a3779539a23cbee38c@syzkaller.appspotmail.com>
Closes: https://syzkaller.appspot.com/bug?extid=00a3779539a23cbee38c
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Fixes: 52ca4b6435a4 ("reiserfs: Switch to security_inode_init_security()")
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/reiserfs/xattr_security.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c
index 6e0a099dd7886..078dd8cc312fc 100644
--- a/fs/reiserfs/xattr_security.c
+++ b/fs/reiserfs/xattr_security.c
@@ -67,6 +67,7 @@ int reiserfs_security_init(struct inode *dir, struct inode *inode,

sec->name = NULL;
sec->value = NULL;
+ sec->length = 0;

/* Don't add selinux attributes on xattrs - they'll never get used */
if (IS_PRIVATE(dir))
--
2.39.2