xfs: xfs_alloc_get_rec should return EFSCORRUPTED for obvious bnobt corruption

Return -EFSCORRUPTED when the bnobt/cntbt return obviously corrupt
values, rather than letting them bounce around in the internal code.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c
index dc9dd38..0214a77 100644 (file)
--- a/fs/xfs/libxfs/xfs_alloc.c
+++ b/fs/xfs/libxfs/xfs_alloc.c
@@ -231,10 +231,14 @@ xfs_alloc_get_rec(
        int                     error;
 
        error = xfs_btree_get_rec(cur, &rec, stat);
-       if (!error && *stat == 1) {
-               *bno = be32_to_cpu(rec->alloc.ar_startblock);
-               *len = be32_to_cpu(rec->alloc.ar_blockcount);
-       }
+       if (error || !(*stat))
+               return error;
+       if (rec->alloc.ar_blockcount == 0)
+               return -EFSCORRUPTED;
+
+       *bno = be32_to_cpu(rec->alloc.ar_startblock);
+       *len = be32_to_cpu(rec->alloc.ar_blockcount);
+
        return error;
 }