Re: [PATCH 04/10] xfs: improve the code that checks recovered rmap intent items

Brian Foster
2020-12-04T14:01:31Z

On Thu, Dec 03, 2020 at 05:12:00PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> The code that validates recovered rmap intent items is kind of a mess --
> it doesn't use the standard xfs type validators, and it doesn't check
> for things that it should. Fix the validator function to use the
> standard validation helpers and look for more types of obvious errors.
>
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---

Reviewed-by: Brian Foster <bfoster@redhat.com>

> fs/xfs/xfs_rmap_item.c | 30 ++++++++++++++++++------------
> 1 file changed, 18 insertions(+), 12 deletions(-)
>
>
> diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
> index d77d104d93c6..f296ec349936 100644
> --- a/fs/xfs/xfs_rmap_item.c
> +++ b/fs/xfs/xfs_rmap_item.c
> @@ -466,11 +466,9 @@ xfs_rui_validate_map(
> struct xfs_mount *mp,
> struct xfs_map_extent *rmap)
> {
> - xfs_fsblock_t startblock_fsb;
> - bool op_ok;
> + if (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS)
> + return false;
>
> - startblock_fsb = XFS_BB_TO_FSB(mp,
> - XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
> switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
> case XFS_RMAP_EXTENT_MAP:
> case XFS_RMAP_EXTENT_MAP_SHARED:
> @@ -480,17 +478,25 @@ xfs_rui_validate_map(
> case XFS_RMAP_EXTENT_CONVERT_SHARED:
> case XFS_RMAP_EXTENT_ALLOC:
> case XFS_RMAP_EXTENT_FREE:
> - op_ok = true;
> break;
> default:
> - op_ok = false;
> - break;
> + return false;
> }
> - if (!op_ok || startblock_fsb == 0 ||
> - rmap->me_len == 0 ||
> - startblock_fsb >= mp->m_sb.sb_dblocks ||
> - rmap->me_len >= mp->m_sb.sb_agblocks ||
> - (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS))
> +
> + if (!XFS_RMAP_NON_INODE_OWNER(rmap->me_owner) &&
> + !xfs_verify_ino(mp, rmap->me_owner))
> + return false;
> +
> + if (rmap->me_startoff + rmap->me_len <= rmap->me_startoff)
> + return false;
> +
> + if (rmap->me_startblock + rmap->me_len <= rmap->me_startblock)
> + return false;
> +
> + if (!xfs_verify_fsbno(mp, rmap->me_startblock))
> + return false;
> +
> + if (!xfs_verify_fsbno(mp, rmap->me_startblock + rmap->me_len - 1))
> return false;
>
> return true;
>