[Patch] quota: do not leak info to user-space

[Cong Wang]

On Mon, 2013-05-13 at 12:18 +0200, Jan Kara wrote:
> On Mon 13-05-13 12:04:23, Jan Kara wrote:
> > On Fri 10-05-13 17:24:33, Cong Wang wrote:
> > > From: Cong Wang <amwang at redhat.com>
> > > 
> > > There is a hole in struct fs_quota_stat, so we have to
> > > zero the struct on stack before copying it to user-space.
> > > 
> > > Cc: Jan Kara <jack at suse.cz>
> > > Signed-off-by: Cong Wang <amwang at redhat.com>
> >   Good point. I've merged the patch.
>   Ah, now I've noticed that XFS (the only user of the callback you are
> fixing) is zeroing the structure on its own (xfs_qm_scall_getqstat). So
> there's no real problem. I'm somewhat wondering whether clearing the field
> in the place where you did it isn't more future-proof but usually we don't
> pass in prezeroed buffers so I've decided to leave things as they are.
> 

You are right. Thanks for looking into this!