xfs: add more checks to superblock validation

There had been reports where xfs filesystem was randomly
corrupted with fsfuzzer, and xfs failed to handle it
gracefully. This patch fixes couple of reported problem
by providing additional checks in the superblock
validation routine.

Signed-off-by: Olaf Weber <olaf@sgi.com>
Reviewed-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index b101990df027120632ff4f486713bc9783e32f31..65a99725d0cc589d9e1b96690a2c12448849e249 100644 (file)
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -291,14 +291,17 @@ xfs_mount_validate_sb(
            sbp->sb_sectsize > XFS_MAX_SECTORSIZE                       ||
            sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG                    ||
            sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG                    ||
+           sbp->sb_sectsize != (1 << sbp->sb_sectlog)                  ||
            sbp->sb_blocksize < XFS_MIN_BLOCKSIZE                       ||
            sbp->sb_blocksize > XFS_MAX_BLOCKSIZE                       ||
            sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG                    ||
            sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG                    ||
+           sbp->sb_blocksize != (1 << sbp->sb_blocklog)                ||
            sbp->sb_inodesize < XFS_DINODE_MIN_SIZE                     ||
            sbp->sb_inodesize > XFS_DINODE_MAX_SIZE                     ||
            sbp->sb_inodelog < XFS_DINODE_MIN_LOG                       ||
            sbp->sb_inodelog > XFS_DINODE_MAX_LOG                       ||
+           sbp->sb_inodesize != (1 << sbp->sb_inodelog)                ||
            (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog)   ||
            (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE)  ||
            (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)  ||