xfs: refactor bmap record validation

Refactor the bmap validator into a more complete helper that looks for
extents that run off the end of the device, overflow into the next AG,
or have invalid flag states.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

1 files changed, 43 insertions, 3 deletions

diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index daae00ed30c5..91214f21563c 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1261,11 +1261,15 @@ xfs_iread_extents(
 		 */
 		frp = XFS_BMBT_REC_ADDR(mp, block, 1);
 		for (j = 0; j < num_recs; j++, frp++, i++) {
+			xfs_failaddr_t	fa;
+
 			xfs_bmbt_disk_get_all(frp, &new);
-			if (!xfs_bmbt_validate_extent(mp, whichfork, &new)) {
-				XFS_ERROR_REPORT("xfs_bmap_read_extents(2)",
-						 XFS_ERRLEVEL_LOW, mp);
+			fa = xfs_bmap_validate_extent(ip, whichfork, &new);
+			if (fa) {
 				error = -EFSCORRUPTED;
+				xfs_inode_verifier_error(ip, error,
+						"xfs_iread_extents(2)",
+						frp, sizeof(*frp), fa);
 				goto out_brelse;
 			}
 			xfs_iext_insert(ip, &icur, &new, state);
@@ -6154,3 +6158,39 @@ xfs_bmap_finish_one(
 
 	return error;
 }
+
+/* Check that an inode's extent does not have invalid flags or bad ranges. */
+xfs_failaddr_t
+xfs_bmap_validate_extent(
+	struct xfs_inode	*ip,
+	int			whichfork,
+	struct xfs_bmbt_irec	*irec)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	xfs_fsblock_t		endfsb;
+	bool			isrt;
+
+	isrt = XFS_IS_REALTIME_INODE(ip);
+	endfsb = irec->br_startblock + irec->br_blockcount - 1;
+	if (isrt) {
+		if (!xfs_verify_rtbno(mp, irec->br_startblock))
+			return __this_address;
+		if (!xfs_verify_rtbno(mp, endfsb))
+			return __this_address;
+	} else {
+		if (!xfs_verify_fsbno(mp, irec->br_startblock))
+			return __this_address;
+		if (!xfs_verify_fsbno(mp, endfsb))
+			return __this_address;
+		if (XFS_FSB_TO_AGNO(mp, irec->br_startblock) !=
+		    XFS_FSB_TO_AGNO(mp, endfsb))
+			return __this_address;
+	}
+	if (irec->br_state != XFS_EXT_NORM) {
+		if (whichfork != XFS_DATA_FORK)
+			return __this_address;
+		if (!xfs_sb_version_hasextflgbit(&mp->m_sb))
+			return __this_address;
+	}
+	return NULL;
+}