From aa88019851a85df80cb77f143758b13aee09e3d9 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Wed, 12 Apr 2023 15:48:50 +1000 Subject: [PATCH] xfs: don't consider future format versions valid In commit fe08cc504448 we reworked the valid superblock version checks. If it is a V5 filesystem, it is always valid, then we checked if the version was less than V4 (reject) and then checked feature fields in the V4 flags to determine if it was valid. What we missed was that if the version is not V4 at this point, we shoudl reject the fs. i.e. the check current treats V6+ filesystems as if it was a v4 filesystem. Fix this. cc: stable@vger.kernel.org Fixes: fe08cc504448 ("xfs: open code sb verifier feature checks") Signed-off-by: Dave Chinner Reviewed-by: Darrick J. Wong Signed-off-by: Dave Chinner --- fs/xfs/libxfs/xfs_sb.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index 99cc03a..ba0f17b 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -72,7 +72,8 @@ xfs_sb_validate_v5_features( } /* - * We support all XFS versions newer than a v4 superblock with V2 directories. + * We current support XFS v5 formats with known features and v4 superblocks with + * at least V2 directories. */ bool xfs_sb_good_version( @@ -86,16 +87,16 @@ xfs_sb_good_version( if (xfs_sb_is_v5(sbp)) return xfs_sb_validate_v5_features(sbp); + /* versions prior to v4 are not supported */ + if (XFS_SB_VERSION_NUM(sbp) != XFS_SB_VERSION_4) + return false; + /* We must not have any unknown v4 feature bits set */ if ((sbp->sb_versionnum & ~XFS_SB_VERSION_OKBITS) || ((sbp->sb_versionnum & XFS_SB_VERSION_MOREBITSBIT) && (sbp->sb_features2 & ~XFS_SB_VERSION2_OKBITS))) return false; - /* versions prior to v4 are not supported */ - if (XFS_SB_VERSION_NUM(sbp) < XFS_SB_VERSION_4) - return false; - /* V4 filesystems need v2 directories and unwritten extents */ if (!(sbp->sb_versionnum & XFS_SB_VERSION_DIRV2BIT)) return false; -- 2.7.4