[PATCH AUTOSEL 6.7 07/88] ocfs2: Avoid touching renamed directory if parent does not change

From: Sasha Levin
Date: Mon Jan 22 2024 - 10:05:14 EST


From: Jan Kara <jack@xxxxxxx>

[ Upstream commit 9d618d19b29c2943527e3a43da0a35aea91062fc ]

The VFS will not be locking moved directory if its parent does not
change. Change ocfs2 rename code to avoid touching renamed directory if
its parent does not change as without locking that can corrupt the
filesystem.

Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ocfs2/namei.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 814733ba2f4b..9221a33f917b 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -1336,7 +1336,7 @@ static int ocfs2_rename(struct mnt_idmap *idmap,
goto bail;
}

- if (S_ISDIR(old_inode->i_mode)) {
+ if (S_ISDIR(old_inode->i_mode) && new_dir != old_dir) {
u64 old_inode_parent;

update_dot_dot = 1;
@@ -1353,8 +1353,7 @@ static int ocfs2_rename(struct mnt_idmap *idmap,
goto bail;
}

- if (!new_inode && new_dir != old_dir &&
- new_dir->i_nlink >= ocfs2_link_max(osb)) {
+ if (!new_inode && new_dir->i_nlink >= ocfs2_link_max(osb)) {
status = -EMLINK;
goto bail;
}
@@ -1601,6 +1600,9 @@ static int ocfs2_rename(struct mnt_idmap *idmap,
mlog_errno(status);
goto bail;
}
+ }
+
+ if (S_ISDIR(old_inode->i_mode)) {
drop_nlink(old_dir);
if (new_inode) {
drop_nlink(new_inode);
--
2.43.0