lkml.org 
[lkml]   [2020]   [Sep]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH 2/3] exfat: remove useless check in exfat_move_file()
Date
> >> --- a/fs/exfat/namei.c
> >> +++ b/fs/exfat/namei.c
> >> @@ -1095,11 +1095,6 @@ static int exfat_move_file(struct inode
> >> *inode, struct exfat_chain *p_olddir,
> >> if (!epmov)
> >> return -EIO;
> >>
> >> - /* check if the source and target directory is the same */
> >> - if (exfat_get_entry_type(epmov) == TYPE_DIR &&
> >> - le32_to_cpu(epmov->dentry.stream.start_clu) == p_newdir->dir)
> >> - return -EINVAL;
> >> -
> >
> > It might check if the cluster numbers are same between source entry
> > and target directory.
>
> This checks if newdir is the move target itself.
> Example:
> mv /mnt/dir0 /mnt/dir0/foo
>
> However, this check is not enough.
> We need to check newdir and all ancestors.
> Example:
> mv /mnt/dir0 /mnt/dir0/dir1/foo
> mv /mnt/dir0 /mnt/dir0/dir1/dir2/foo
> ...
>
> This is probably a taboo for all layered filesystems.
>
>
> > Could you let me know what code you mentioned?
> > Or do you mean the codes on vfs?
>
> You can find in do_renameat2(). --- around 'fs/namei.c:4440'
> If the destination ancestors are itself, our driver will not be called.

I think, of course, vfs has been doing that.
So that code is unnecessary in normal situations.

That code comes from the old exfat implementation.
And as far as I understand, it seems to check once more "the cluster number"
even though it comes through vfs so that it tries detecting abnormal of on-disk.

Anyway, I agonized if it is really needed.
In conclusion, old code could be eliminated and your patch looks reasonable.
Thanks

Acked-by: Sungjong Seo <sj1557.seo@samsung.com>

>
>
> BTW
> Are you busy now?
I'm sorry, I'm so busy for my full time work :(
Anyway, I'm trying to review serious bug patches or bug reports first.
Other patches, such as clean-up or code refactoring, may take some time to review.

> I am waiting for your reply about "integrates dir-entry getting and
> validation" patch.
As I know, your patch is being under review by Namjae.

>
> BR
> ---
> Tetsuhiro Kohada <kohada.t2@gmail.com>

\
 
 \ /
  Last update: 2020-09-28 09:37    [W:0.077 / U:26.468 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site