From c18679ebd86857d4dae5a7462f38c4c98d8445de Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 26 Aug 2019 15:40:38 +0800 Subject: btrfs: tree-checker: Try to detect missing INODE_ITEM For the following items, key->objectid is inode number: - DIR_ITEM - DIR_INDEX - XATTR_ITEM - EXTENT_DATA - INODE_REF So in the subvolume tree, such items must have its previous item share the same objectid, e.g.: (257 INODE_ITEM 0) (257 DIR_INDEX xxx) (257 DIR_ITEM xxx) (258 INODE_ITEM 0) (258 INODE_REF 0) (258 XATTR_ITEM 0) (258 EXTENT_DATA 0) But if we have the following sequence, then there is definitely something wrong, normally some INODE_ITEM is missing, like: (257 INODE_ITEM 0) (257 DIR_INDEX xxx) (257 DIR_ITEM xxx) (258 XATTR_ITEM 0) <<< objecitd suddenly changed to 258 (258 EXTENT_DATA 0) So just by checking the previous key for above inode based key types, we can detect a missing inode item. For INODE_REF key type, the check will be added along with INODE_REF checker. Reviewed-by: Nikolay Borisov Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/tree-checker.c | 27 +++++++++++++++++++++++++-- 1 file changed, 25 insertions(+), 2 deletions(-) (limited to 'fs/btrfs/tree-checker.c') diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index 076d5b8014fb..5aca82e67309 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -141,6 +141,20 @@ static int check_extent_data_item(struct extent_buffer *leaf, return -EUCLEAN; } + /* + * Previous key must have the same key->objectid (ino). + * It can be XATTR_ITEM, INODE_ITEM or just another EXTENT_DATA. + * But if objectids mismatch, it means we have a missing + * INODE_ITEM. + */ + if (slot > 0 && is_fstree(btrfs_header_owner(leaf)) && + prev_key->objectid != key->objectid) { + file_extent_err(leaf, slot, + "invalid previous key objectid, have %llu expect %llu", + prev_key->objectid, key->objectid); + return -EUCLEAN; + } + fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); if (btrfs_file_extent_type(leaf, fi) > BTRFS_FILE_EXTENT_TYPES) { @@ -299,13 +313,22 @@ static void dir_item_err(const struct extent_buffer *eb, int slot, } static int check_dir_item(struct extent_buffer *leaf, - struct btrfs_key *key, int slot) + struct btrfs_key *key, struct btrfs_key *prev_key, + int slot) { struct btrfs_fs_info *fs_info = leaf->fs_info; struct btrfs_dir_item *di; u32 item_size = btrfs_item_size_nr(leaf, slot); u32 cur = 0; + /* Same check as in check_extent_data_item() */ + if (slot > 0 && is_fstree(btrfs_header_owner(leaf)) && + prev_key->objectid != key->objectid) { + dir_item_err(leaf, slot, + "invalid previous key objectid, have %llu expect %llu", + prev_key->objectid, key->objectid); + return -EUCLEAN; + } di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item); while (cur < item_size) { u32 name_len; @@ -1244,7 +1267,7 @@ static int check_leaf_item(struct extent_buffer *leaf, case BTRFS_DIR_ITEM_KEY: case BTRFS_DIR_INDEX_KEY: case BTRFS_XATTR_ITEM_KEY: - ret = check_dir_item(leaf, key, slot); + ret = check_dir_item(leaf, key, prev_key, slot); break; case BTRFS_BLOCK_GROUP_ITEM_KEY: ret = check_block_group_item(leaf, key, slot); -- cgit v1.2.3