On Fri, Apr 17, 2020 at 11:08:53AM -0400, Brian Foster wrote:
> The dquot read/write verifier calls xfs_dqblk_verify() on every
> dquot in the buffer. Remove the duplicate call from
> xfs_qm_dqflush().
Ah, I think there's a bug here - it's not supposed to be a
duplicate....
> Signed-off-by: Brian Foster <bfoster@xxxxxxxxxx>
> ---
> fs/xfs/xfs_dquot.c | 14 --------------
> 1 file changed, 14 deletions(-)
>
> diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c
> index af2c8e5ceea0..73032c18a94a 100644
> --- a/fs/xfs/xfs_dquot.c
> +++ b/fs/xfs/xfs_dquot.c
> @@ -1071,7 +1071,6 @@ xfs_qm_dqflush(
> struct xfs_buf *bp;
> struct xfs_dqblk *dqb;
> struct xfs_disk_dquot *ddqp;
> - xfs_failaddr_t fa;
> int error;
>
> ASSERT(XFS_DQ_IS_LOCKED(dqp));
> @@ -1116,19 +1115,6 @@ xfs_qm_dqflush(
> dqb = bp->b_addr + dqp->q_bufoffset;
> ddqp = &dqb->dd_diskdq;
>
> - /*
> - * A simple sanity check in case we got a corrupted dquot.
> - */
> - fa = xfs_dqblk_verify(mp, dqb, be32_to_cpu(ddqp->d_id), 0);
So this verifies the on disk dquot ....
> - if (fa) {
> - xfs_alert(mp, "corrupt dquot ID 0x%x in memory at %pS",
...which issues an "in memory corruption" alert on failure...
> - be32_to_cpu(ddqp->d_id), fa);
> - xfs_buf_relse(bp);
> - xfs_dqfunlock(dqp);
> - xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
> - return -EFSCORRUPTED;
> - }
> -
> /* This is the only portion of data that needs to persist */
> memcpy(ddqp, &dqp->q_core, sizeof(struct xfs_disk_dquot));
.... and on success we immediately overwrite the on-disk copy with
the unchecked in-memory copy of the dquot.
IOWs, I think that verification call here should be checking the
in-memory dquot core, not the on disk buffer that is about to get
trashed. i.e. something like this:
- fa = xfs_dqblk_verify(mp, dqb, be32_to_cpu(ddqp->d_id), 0);
+ fa = xfs_dquot_verify(mp, &dqp->q_core, be32_to_cpu(ddqp->d_id), 0);
Cheers,
Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
