Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / fs / xfs / xfs_alloc.c

diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index 4bc3c64..27d64d7 100644 (file)
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -2395,17 +2395,33 @@ xfs_free_extent(
        memset(&args, 0, sizeof(xfs_alloc_arg_t));
        args.tp = tp;
        args.mp = tp->t_mountp;
+
+       /*
+        * validate that the block number is legal - the enables us to detect
+        * and handle a silent filesystem corruption rather than crashing.
+        */
        args.agno = XFS_FSB_TO_AGNO(args.mp, bno);
-       ASSERT(args.agno < args.mp->m_sb.sb_agcount);
+       if (args.agno >= args.mp->m_sb.sb_agcount)
+               return EFSCORRUPTED;
+
        args.agbno = XFS_FSB_TO_AGBNO(args.mp, bno);
+       if (args.agbno >= args.mp->m_sb.sb_agblocks)
+               return EFSCORRUPTED;
+
        args.pag = xfs_perag_get(args.mp, args.agno);
-       if ((error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING)))
+       ASSERT(args.pag);
+
+       error = xfs_alloc_fix_freelist(&args, XFS_ALLOC_FLAG_FREEING);
+       if (error)
                goto error0;
-#ifdef DEBUG
-       ASSERT(args.agbp != NULL);
-       ASSERT((args.agbno + len) <=
-               be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length));
-#endif
+
+       /* validate the extent size is legal now we have the agf locked */
+       if (args.agbno + len >
+                       be32_to_cpu(XFS_BUF_TO_AGF(args.agbp)->agf_length)) {
+               error = EFSCORRUPTED;
+               goto error0;
+       }
+
        error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0);
 error0:
        xfs_perag_put(args.pag);