From 33005fd0a537501111fc97ec330b721388c6b451 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 4 Dec 2020 13:28:35 -0800 Subject: [PATCH] xfs: refactor file range validation Refactor all the open-coded validation of file block ranges into a single helper, and teach the bmap scrubber to check the ranges. Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster Reviewed-by: Dave Chinner Reviewed-by: Christoph Hellwig --- fs/xfs/libxfs/xfs_bmap.c | 2 +- fs/xfs/libxfs/xfs_types.c | 25 +++++++++++++++++++++++++ fs/xfs/libxfs/xfs_types.h | 3 +++ fs/xfs/scrub/bmap.c | 4 ++++ fs/xfs/xfs_bmap_item.c | 2 +- fs/xfs/xfs_inode.c | 2 +- fs/xfs/xfs_rmap_item.c | 2 +- fs/xfs/xfs_super.c | 2 +- 8 files changed, 37 insertions(+), 5 deletions(-) diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 7bcf498ef6b2..dcf56bcafb8f 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -6227,7 +6227,7 @@ xfs_bmap_validate_extent( { struct xfs_mount *mp = ip->i_mount; - if (irec->br_startoff + irec->br_blockcount <= irec->br_startoff) + if (!xfs_verify_fileext(mp, irec->br_startoff, irec->br_blockcount)) return __this_address; if (XFS_IS_REALTIME_INODE(ip) && whichfork == XFS_DATA_FORK) { diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c index 7b310eb296b7..b254fbeaaa50 100644 --- a/fs/xfs/libxfs/xfs_types.c +++ b/fs/xfs/libxfs/xfs_types.c @@ -258,3 +258,28 @@ xfs_verify_dablk( return dabno <= max_dablk; } + +/* Check that a file block offset does not exceed the maximum. */ +bool +xfs_verify_fileoff( + struct xfs_mount *mp, + xfs_fileoff_t off) +{ + return off <= XFS_MAX_FILEOFF; +} + +/* Check that a range of file block offsets do not exceed the maximum. */ +bool +xfs_verify_fileext( + struct xfs_mount *mp, + xfs_fileoff_t off, + xfs_fileoff_t len) +{ + if (off + len <= off) + return false; + + if (!xfs_verify_fileoff(mp, off)) + return false; + + return xfs_verify_fileoff(mp, off + len - 1); +} diff --git a/fs/xfs/libxfs/xfs_types.h b/fs/xfs/libxfs/xfs_types.h index 18e83ce46568..064bd6e8c922 100644 --- a/fs/xfs/libxfs/xfs_types.h +++ b/fs/xfs/libxfs/xfs_types.h @@ -203,5 +203,8 @@ bool xfs_verify_icount(struct xfs_mount *mp, unsigned long long icount); bool xfs_verify_dablk(struct xfs_mount *mp, xfs_fileoff_t off); void xfs_icount_range(struct xfs_mount *mp, unsigned long long *min, unsigned long long *max); +bool xfs_verify_fileoff(struct xfs_mount *mp, xfs_fileoff_t off); +bool xfs_verify_fileext(struct xfs_mount *mp, xfs_fileoff_t off, + xfs_fileoff_t len); #endif /* __XFS_TYPES_H__ */ diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c index cce8ac7d3973..bce4421acdb9 100644 --- a/fs/xfs/scrub/bmap.c +++ b/fs/xfs/scrub/bmap.c @@ -329,6 +329,10 @@ xchk_bmap_iextent( xchk_fblock_set_corrupt(info->sc, info->whichfork, irec->br_startoff); + if (!xfs_verify_fileext(mp, irec->br_startoff, irec->br_blockcount)) + xchk_fblock_set_corrupt(info->sc, info->whichfork, + irec->br_startoff); + xchk_bmap_dirattr_extent(ip, info, irec); /* There should never be a "hole" extent in either extent list. */ diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c index 659bde22c505..93e4d8ae6e92 100644 --- a/fs/xfs/xfs_bmap_item.c +++ b/fs/xfs/xfs_bmap_item.c @@ -445,7 +445,7 @@ xfs_bui_validate( if (!xfs_verify_ino(mp, bmap->me_owner)) return false; - if (bmap->me_startoff + bmap->me_len <= bmap->me_startoff) + if (!xfs_verify_fileext(mp, bmap->me_startoff, bmap->me_len)) return false; return xfs_verify_fsbext(mp, bmap->me_startblock, bmap->me_len); diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 2bfbcf28b1bd..004fce3646ae 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -1521,7 +1521,7 @@ xfs_itruncate_extents_flags( * the page cache can't scale that far. */ first_unmap_block = XFS_B_TO_FSB(mp, (xfs_ufsize_t)new_size); - if (first_unmap_block >= XFS_MAX_FILEOFF) { + if (!xfs_verify_fileoff(mp, first_unmap_block)) { WARN_ON_ONCE(first_unmap_block > XFS_MAX_FILEOFF); return 0; } diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c index 4fa875237422..49cebd68b672 100644 --- a/fs/xfs/xfs_rmap_item.c +++ b/fs/xfs/xfs_rmap_item.c @@ -490,7 +490,7 @@ xfs_rui_validate_map( !xfs_verify_ino(mp, rmap->me_owner)) return false; - if (rmap->me_startoff + rmap->me_len <= rmap->me_startoff) + if (!xfs_verify_fileext(mp, rmap->me_startoff, rmap->me_len)) return false; return xfs_verify_fsbext(mp, rmap->me_startblock, rmap->me_len); diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 36002f460d7c..e1668491cee7 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -1517,7 +1517,7 @@ xfs_fc_fill_super( * Avoid integer overflow by comparing the maximum bmbt offset to the * maximum pagecache offset in units of fs blocks. */ - if (XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE) > XFS_MAX_FILEOFF) { + if (!xfs_verify_fileoff(mp, XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE))) { xfs_warn(mp, "MAX_LFS_FILESIZE block offset (%llu) exceeds extent map maximum (%llu)!", XFS_B_TO_FSBT(mp, MAX_LFS_FILESIZE), -- 2.39.5