| Message ID | 20190826074039.28517-2-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: tree-checker: Add checks to detect missing INODE_ITEM | expand |
On 26.08.19 г. 10:40 ч., Qu Wenruo wrote: > For the following items, key->objectid is inode number: > - DIR_ITEM > - DIR_INDEX > - XATTR_ITEM > - EXTENT_DATA > - INODE_REF > > So in btrfs btree, such items must have its previous item shares 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 missing inode item. > > For INODE_REF key type, the check will be added along with INODE_REF > checker. > > Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> > --- > fs/btrfs/tree-checker.c | 25 +++++++++++++++++++++++-- > 1 file changed, 23 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c > index ccd5706199d7..636ce1b4566e 100644 > --- a/fs/btrfs/tree-checker.c > +++ b/fs/btrfs/tree-checker.c > @@ -141,6 +141,19 @@ 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 && 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 +312,21 @@ 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 && 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; > @@ -841,7 +862,7 @@ 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); >
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index ccd5706199d7..636ce1b4566e 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -141,6 +141,19 @@ 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 && 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 +312,21 @@ 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 && 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; @@ -841,7 +862,7 @@ 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);
For the following items, key->objectid is inode number: - DIR_ITEM - DIR_INDEX - XATTR_ITEM - EXTENT_DATA - INODE_REF So in btrfs btree, such items must have its previous item shares 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 missing inode item. For INODE_REF key type, the check will be added along with INODE_REF checker. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/tree-checker.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-)