Re: [PATCH 06/10] xfs: improve the code that checks recovered refcount intent items

Brian Foster
2020-12-04T14:01:45Z

On Thu, Dec 03, 2020 at 05:12:12PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
>
> The code that validates recovered refcount 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: Christoph Hellwig <hch@lst.de>
> ---

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

> fs/xfs/xfs_refcount_item.c | 23 +++++++++++------------
> 1 file changed, 11 insertions(+), 12 deletions(-)
>
>
> diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
> index a456a2fb794c..8ad6c81f6d8f 100644
> --- a/fs/xfs/xfs_refcount_item.c
> +++ b/fs/xfs/xfs_refcount_item.c
> @@ -423,27 +423,26 @@ xfs_cui_validate_phys(
> struct xfs_mount *mp,
> struct xfs_phys_extent *refc)
> {
> - xfs_fsblock_t startblock_fsb;
> - bool op_ok;
> + if (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
> + return false;
>
> - startblock_fsb = XFS_BB_TO_FSB(mp,
> - XFS_FSB_TO_DADDR(mp, refc->pe_startblock));
> switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
> case XFS_REFCOUNT_INCREASE:
> case XFS_REFCOUNT_DECREASE:
> case XFS_REFCOUNT_ALLOC_COW:
> case XFS_REFCOUNT_FREE_COW:
> - op_ok = true;
> break;
> default:
> - op_ok = false;
> - break;
> + return false;
> }
> - if (!op_ok || startblock_fsb == 0 ||
> - refc->pe_len == 0 ||
> - startblock_fsb >= mp->m_sb.sb_dblocks ||
> - refc->pe_len >= mp->m_sb.sb_agblocks ||
> - (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS))
> +
> + if (refc->pe_startblock + refc->pe_len <= refc->pe_startblock)
> + return false;
> +
> + if (!xfs_verify_fsbno(mp, refc->pe_startblock))
> + return false;
> +
> + if (!xfs_verify_fsbno(mp, refc->pe_startblock + refc->pe_len - 1))
> return false;
>
> return true;
>