From 3f94c441e2c3dea029a46a2326b2170acf2c7713 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 21 Jun 2016 11:53:28 +1000 Subject: [PATCH] xfs: check offsets of variable length structures Some of the directory/attr structures contain variable-length objects, so the enclosing structure doesn't have a meaningful fixed size at compile time. We can check the offsets of the members before the variable-length member, so do those. Signed-off-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Signed-off-by: Dave Chinner --- fs/xfs/xfs_ondisk.h | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h index 184c44effdd5..027230134098 100644 --- a/fs/xfs/xfs_ondisk.h +++ b/fs/xfs/xfs_ondisk.h @@ -22,6 +22,11 @@ BUILD_BUG_ON_MSG(sizeof(structname) != (size), "XFS: sizeof(" \ #structname ") is wrong, expected " #size) +#define XFS_CHECK_OFFSET(structname, member, off) \ + BUILD_BUG_ON_MSG(offsetof(structname, member) != (off), \ + "XFS: offsetof(" #structname ", " #member ") is wrong, " \ + "expected " #off) + static inline void __init xfs_check_ondisk_structs(void) { @@ -75,15 +80,28 @@ xfs_check_ondisk_structs(void) XFS_CHECK_STRUCT_SIZE(xfs_attr_leaf_name_remote_t, 12); */ + XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, valuelen, 0); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, namelen, 2); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_local_t, nameval, 3); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, valueblk, 0); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, valuelen, 4); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, namelen, 8); + XFS_CHECK_OFFSET(xfs_attr_leaf_name_remote_t, name, 9); XFS_CHECK_STRUCT_SIZE(xfs_attr_leafblock_t, 40); - XFS_CHECK_STRUCT_SIZE(xfs_attr_shortform_t, 8); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, hdr.totsize, 0); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, hdr.count, 2); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].namelen, 4); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].valuelen, 5); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].flags, 6); + XFS_CHECK_OFFSET(xfs_attr_shortform_t, list[0].nameval, 7); XFS_CHECK_STRUCT_SIZE(xfs_da_blkinfo_t, 12); XFS_CHECK_STRUCT_SIZE(xfs_da_intnode_t, 16); XFS_CHECK_STRUCT_SIZE(xfs_da_node_entry_t, 8); XFS_CHECK_STRUCT_SIZE(xfs_da_node_hdr_t, 16); XFS_CHECK_STRUCT_SIZE(xfs_dir2_data_free_t, 4); XFS_CHECK_STRUCT_SIZE(xfs_dir2_data_hdr_t, 16); - XFS_CHECK_STRUCT_SIZE(xfs_dir2_data_unused_t, 6); + XFS_CHECK_OFFSET(xfs_dir2_data_unused_t, freetag, 0); + XFS_CHECK_OFFSET(xfs_dir2_data_unused_t, length, 2); XFS_CHECK_STRUCT_SIZE(xfs_dir2_free_hdr_t, 16); XFS_CHECK_STRUCT_SIZE(xfs_dir2_free_t, 16); XFS_CHECK_STRUCT_SIZE(xfs_dir2_ino4_t, 4); @@ -94,6 +112,9 @@ xfs_check_ondisk_structs(void) XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_t, 16); XFS_CHECK_STRUCT_SIZE(xfs_dir2_leaf_tail_t, 4); XFS_CHECK_STRUCT_SIZE(xfs_dir2_sf_entry_t, 3); + XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, namelen, 0); + XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, offset, 1); + XFS_CHECK_OFFSET(xfs_dir2_sf_entry_t, name, 3); XFS_CHECK_STRUCT_SIZE(xfs_dir2_sf_hdr_t, 10); XFS_CHECK_STRUCT_SIZE(xfs_dir2_sf_off_t, 2); -- 2.20.1