xfs: improve the code that checks recovered bmap intent items
authorDarrick J. Wong <darrick.wong@oracle.com>
Mon, 30 Nov 2020 00:33:36 +0000 (16:33 -0800)
committerDarrick J. Wong <darrick.wong@oracle.com>
Wed, 9 Dec 2020 17:49:38 +0000 (09:49 -0800)
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>
Reviewed-by: Brian Foster <bfoster@redhat.com>
fs/xfs/xfs_bmap_item.c

index 9be61feca65b41e4ef465671ae05e9f6d2748133..a21a9f71c0c0c182176a7c6e031ae5ec00092a67 100644 (file)
@@ -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;