Re: [PATCH] ext3: fix a bug when we try to open a file with O_TMPFILE flag

[Jan Kara <jack@suse.cz>]

On Mon 22-07-13 21:14:07, Zheng Liu wrote:
> Hi Jan,
> 
> On Mon, Jul 22, 2013 at 03:07:37PM +0200, Jan Kara wrote:
> > On Sun 21-07-13 00:53:47, Zheng Liu wrote:
> > > From: Zheng Liu <wenqing.lz@taobao.com>
> > > 
> > > When we try to open a file with O_TMPFILE flag, we will trigger a bug.
> > > The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and
> > > this check always fails because we set ->i_nlink = 1 in
> > > inode_init_always().  We can use the following program to trigger it:
> [...]
> > > Here we couldn't call clear_nlink() directly because in d_tmpfile() we
> > > will call inode_dec_link_count() to decrease ->i_nlink.  So this commit
> > > tries to call d_tmpfile() before ext4_orphan_add() to fix this problem.
> >   Thanks the patch looks good. I've added the patch to my tree and will
> > push it to Linus soon.
> 
> Thanks for your review.  Ted has pick it up and Linus has pulled the
> patch.  Sorry, I forgot to remind you.
> 
> http://www.gossamer-threads.com/lists/linux/kernel/1750649
  Yeah, I've just noticed when I updated my tree. No problem.

								Honza

-- 
Jan Kara <jack@suse.cz>
SUSE Labs, CR