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

["Darrick J. Wong" <darrick.wong@xxxxxxxxxx>]

From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>

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@xxxxxxxxxx>
---
 fs/xfs/xfs_refcount_item.c |   24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)


diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
index de344bd7e73c..20e5c22bb754 100644
--- a/fs/xfs/xfs_refcount_item.c
+++ b/fs/xfs/xfs_refcount_item.c
@@ -423,27 +423,27 @@ xfs_cui_validate_phys(
 	struct xfs_mount		*mp,
 	struct xfs_phys_extent		*refc)
 {
-	xfs_fsblock_t			startblock_fsb;
-	bool				op_ok;
+	xfs_fsblock_t			end;
+
+	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;
+
+	end = refc->pe_startblock + refc->pe_len - 1;
+	if (!xfs_verify_fsbno(mp, refc->pe_startblock) ||
+	    !xfs_verify_fsbno(mp, end))
 		return false;
 
 	return true;