On Wed, Jul 01, 2020 at 09:42:08AM +0100, Christoph Hellwig wrote:
> On Tue, Jun 30, 2020 at 08:42:09AM -0700, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> >
> > While loading dquot records off disk, make sure that the quota type
> > flags are the same between the incore dquot and the ondisk dquot.
> >
> > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
> > ---
> > fs/xfs/xfs_dquot.c | 23 ++++++++++++++++++++---
> > 1 file changed, 20 insertions(+), 3 deletions(-)
> >
> >
> > diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> > index d5b7f03e93c8..46c8ca83c04d 100644
> > --- a/fs/xfs/xfs_dquot.c
> > +++ b/fs/xfs/xfs_dquot.c
> > @@ -524,13 +524,27 @@ xfs_dquot_alloc(
> > }
> >
> > /* Copy the in-core quota fields in from the on-disk buffer. */
> > -STATIC void
> > +STATIC int
> > xfs_dquot_from_disk(
> > struct xfs_dquot *dqp,
> > struct xfs_buf *bp)
> > {
> > struct xfs_disk_dquot *ddqp = bp->b_addr + dqp->q_bufoffset;
> >
> > + /*
> > + * The only field the verifier didn't check was the quota type flag, so
> > + * do that here.
> > + */
> > + if ((dqp->dq_flags & XFS_DQ_ALLTYPES) !=
> > + (ddqp->d_flags & XFS_DQ_ALLTYPES) ||
> > + dqp->q_core.d_id != ddqp->d_id) {
>
> The comment looks a little weird, as this also checks d_id. Also
> xfs_dquot_verify verifies d_flags against generally bogus value, it
> just doesn't check that it matches the type we are looking for.
> Last but not least dqp->dq_flags only contains the type at this
> point.
>
> So what about something like:
>
> /*
> * Ensure we got the type and ID we were looking for. Everything else
> * we checked by the verifier.
> */
> if ((ddqp->d_flags & XFS_DQ_ALLTYPES) != dqp->dq_flags ||
> ddqp->d_id != dqp->q_core.d_id)
Sounds good to me. I'll make that change.
--D
>
