[PATCH 02/10] xfs: improve the code that checks recovered bmap intent items

Darrick J. Wong
2020-12-04T01:12:48Z

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered bmap 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>
---
fs/xfs/xfs_bmap_item.c | 26 +++++++++++++-------------
1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index 555453d0e080..78346d47564b 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -424,18 +424,12 @@ xfs_bui_validate(
struct xfs_bui_log_item *buip)
{
struct xfs_map_extent *bmap;
- xfs_fsblock_t startblock_fsb;
- xfs_fsblock_t inode_fsb;

/* Only one mapping operation per BUI... */
if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
return false;

bmap = &buip->bui_format.bui_extents[0];
- startblock_fsb = XFS_BB_TO_FSB(mp,
- XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
- inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
- XFS_INO_TO_FSB(mp, bmap->me_owner)));

if (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)
return false;
@@ -448,13 +442,19 @@ xfs_bui_validate(
return false;
}

- if (startblock_fsb == 0 ||
- bmap->me_len == 0 ||
- inode_fsb == 0 ||
- startblock_fsb >= mp->m_sb.sb_dblocks ||
- bmap->me_len >= mp->m_sb.sb_agblocks ||
- inode_fsb >= mp->m_sb.sb_dblocks ||
- (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS))
+ if (!xfs_verify_ino(mp, bmap->me_owner))
+ return false;
+
+ if (bmap->me_startoff + bmap->me_len <= bmap->me_startoff)
+ return false;
+
+ if (bmap->me_startblock + bmap->me_len <= bmap->me_startblock)
+ return false;
+
+ if (!xfs_verify_fsbno(mp, bmap->me_startblock))
+ return false;
+
+ if (!xfs_verify_fsbno(mp, bmap->me_startblock + bmap->me_len - 1))
return false;

return true;