Re: [PATCH] minix: fix bug when opening a file with O_DIRECT will

[Christian Brauner]

On Fri, Jan 07, 2022 at 07:12:39AM +0800, Qinghua Jin wrote:
> On Thu, Jan 6, 2022 at 11:43 PM Jan Kara <jack@xxxxxxx> wrote:
> 
> > On Thu 06-01-22 11:30:41, Qinghua Jin wrote:
> > > Testcase:
> > > 1. create a minix file system and mount it
> > > 2. open a file on the file system with O_RDWR|O_CREAT|O_TRUNC|O_DIRECT
> > > 3. open fails with -EINVAL but leaves an empty file behind. All other
> > > open() failures don't leave the failed open files behind.
> > >
> > > It is hard to check the direct_IO op before creating the inode. Just as
> > > ext4 and btrfs do, this patch will resolve the issue by allowing to
> > > create the file with O_DIRECT but returning error when writing the file.
> > >
> > > Signed-off-by: Qinghua Jin <qhjin.dev@xxxxxxxxx>
> >
> > The patch looks good. Thanks. Feel free to add:
> >
> > Reviewed-by: Jan Kara <jack@xxxxxxx>
> >
> > Just out of curiosity: Do you happen to really use minix filesystem or was
> > this just a fallout from some fuzz testing or something like that?
> >
> > Thanks, It's a bug reported by colin.king@xxxxxxxxxxxxx
> https://bugzilla.kernel.org/show_bug.cgi?id=213041
> I don't include the email because it's not reachable.

Fwiw, Colin's now at Intel:
Colin Ian King <colin.king@xxxxxxxxx>

(While I'm here:
 Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>)