Re: [PATCH 2/4] xfs: validate the realtime geometry in xfs_validate_sb_common

Chandan Rajendra
2020-04-01T13:47:02Z

On Wednesday, March 25, 2020 8:54 AM Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> Validate the geometry of the realtime geometry when we mount the
> filesystem, so that we don't abruptly shut down the filesystem later on.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

The changes look logically correct.

Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>

> ---
> fs/xfs/libxfs/xfs_sb.c | 35 +++++++++++++++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
>
>
> diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
> index 2f60fc3c99a0..dee0a1a594dc 100644
> --- a/fs/xfs/libxfs/xfs_sb.c
> +++ b/fs/xfs/libxfs/xfs_sb.c
> @@ -328,6 +328,41 @@ xfs_validate_sb_common(
> return -EFSCORRUPTED;
> }
>
> + /* Validate the realtime geometry; stolen from xfs_repair */
> + if (unlikely(
> + sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE ||
> + sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)) {
> + xfs_notice(mp,
> + "realtime extent sanity check failed");
> + return -EFSCORRUPTED;
> + }
> +
> + if (sbp->sb_rblocks == 0) {
> + if (unlikely(
> + sbp->sb_rextents != 0 ||
> + sbp->sb_rbmblocks != 0 ||
> + sbp->sb_rextslog != 0 ||
> + sbp->sb_frextents != 0)) {
> + xfs_notice(mp,
> + "realtime zeroed geometry sanity check failed");
> + return -EFSCORRUPTED;
> + }
> + } else {
> + xfs_rtblock_t rexts;
> + uint32_t temp;
> +
> + rexts = div_u64_rem(sbp->sb_rblocks, sbp->sb_rextsize, &temp);
> + if (unlikely(
> + rexts != sbp->sb_rextents ||
> + sbp->sb_rextslog != xfs_highbit32(sbp->sb_rextents) ||
> + sbp->sb_rbmblocks != howmany(sbp->sb_rextents,
> + NBBY * sbp->sb_blocksize))) {
> + xfs_notice(mp,
> + "realtime geometry sanity check failed");
> + return -EFSCORRUPTED;
> + }
> + }
> +
> if (sbp->sb_unit) {
> if (!xfs_sb_version_hasdalign(sbp) ||
> sbp->sb_unit > sbp->sb_width ||
>
>

--
chandan