mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-04 18:09:57 +00:00
Code Issues Releases Wiki Activity

ext4: Fix possible corruption when moving a directory

Browse source 
[ Upstream commit 0813299c58 ]

When we are renaming a directory to a different directory, we need to
update '..' entry in the moved directory. However nothing prevents moved
directory from being modified and even converted from the inline format
to the normal format. When such race happens the rename code gets
confused and we crash. Fix the problem by locking the moved directory.

CC: stable@vger.kernel.org
Fixes: 32f7f22c0b ("ext4: let ext4_rename handle inline dir")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230126112221.11866-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jan Kara 2023-01-26 12:22:21 +01:00 committed by Greg Kroah-Hartman
parent 891a3cba42
commit 8dac5a63cf
1 changed files with 10 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
fs/ext4/namei.c
View file

@ -3855,9 +3855,16 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir))
goto end_rename;
}
/*
* We need to protect against old.inode directory getting
* converted from inline directory format into a normal one.
*/
inode_lock_nested(old.inode, I_MUTEX_NONDIR2);
retval = ext4_rename_dir_prepare(handle, &old);
if (retval)
if (retval) {
inode_unlock(old.inode);
goto end_rename;
}
}
/*
* If we're renaming a file within an inline_data dir and adding or
@ -3953,6 +3960,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
} else {
ext4_journal_stop(handle);
}
if (old.dir_bh)
inode_unlock(old.inode);
release_bh:
brelse(old.dir_bh);
brelse(old.bh);