[PATCH 26/51] xfs_repair: mask off length appropriately

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

Ensure that we remove the flag bits from blockcount before using the
length field.

Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
 repair/scan.c |   32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)


diff --git a/repair/scan.c b/repair/scan.c
index c1ab6df..1ade344 100644
--- a/repair/scan.c
+++ b/repair/scan.c
@@ -792,6 +792,8 @@ scan_rmapbt(
        int                     numrecs;
        int                     state;
        xfs_agblock_t           lastblock = 0;
+       int64_t                 lastowner = 0;
+       int64_t                 lastoffset = 0;
 
        if (magic != XFS_RMAP_CRC_MAGIC) {
                name = "(unknown)";
@@ -859,11 +861,12 @@ _("%s rmap btree block claimed (state %d), agno %d, bno 
%d, suspect %d\n"),
                for (i = 0; i < numrecs; i++) {
                        xfs_agblock_t           b, end;
                        xfs_extlen_t            len, blen;
-                       int64_t                 owner;
+                       int64_t                 owner, offset;
 
                        b = be32_to_cpu(rp[i].rm_startblock);
-                       len = be32_to_cpu(rp[i].rm_blockcount);
+                       len = XFS_RMAP_LEN(be32_to_cpu(rp[i].rm_blockcount));
                        owner = be64_to_cpu(rp[i].rm_owner);
+                       offset = be64_to_cpu(rp[i].rm_offset);
                        end = b + len;
 
                        if (!verify_agbno(mp, agno, b)) {
@@ -879,14 +882,27 @@ _("%s rmap btree block claimed (state %d), agno %d, bno 
%d, suspect %d\n"),
                                continue;
                        }
 
-                       /* XXX: range check owner */
+                       if (!(owner > 0 || (owner > XFS_RMAP_OWN_MIN &&
+                                           owner <= XFS_RMAP_OWN_FS)))
+                               do_warn(
+       _("invalid owner in rmap btree record %d (%"PRId64" %u) block %u/%u\n"),
+                                               i, owner, len, agno, bno);
 
-                       if (b && b <= lastblock) {
-                               do_warn(_(
-       "out-of-order rmap btree record %d (%u %u) block %u/%u\n"),
-                                       i, b, len, agno, bno);
-                       } else {
+                       if (i == 0) {
+advance:
                                lastblock = b;
+                               lastowner = owner;
+                               lastoffset = offset;
+                       } else {
+                               bool bad;
+
+                               bad = b <= lastblock;
+                               if (bad)
+                                       do_warn(
+       _("out-of-order rmap btree record %d (%u %"PRId64" %"PRIx64" %u) block 
%u/%u\n"),
+                                       i, b, owner, offset, len, agno, bno);
+                               else
+                                       goto advance;
                        }
 
                        for ( ; b < end; b += blen)  {