From 0785a9aacf9de9cd6a89a628b3b5d6b7e9ce5316 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Fri, 9 Aug 2019 09:24:24 +0800 Subject: [PATCH] btrfs: tree-checker: Add EXTENT_DATA_REF check EXTENT_DATA_REF is a little like DIR_ITEM which contains hash in its key->offset. This patch will check the following contents: - Key->objectid Basic alignment check. - Hash Hash of each extent_data_ref item must match key->offset. - Offset Basic alignment check. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/ctree.h | 1 + fs/btrfs/extent-tree.c | 2 +- fs/btrfs/tree-checker.c | 48 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 50 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index b161224b5a0b..20793742c9d3 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2447,6 +2447,7 @@ enum btrfs_inline_ref_type { int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb, struct btrfs_extent_inline_ref *iref, enum btrfs_inline_ref_type is_data); +u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset); u64 btrfs_csum_bytes_to_leaves(struct btrfs_fs_info *fs_info, u64 csum_bytes); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index cd210550a349..5e8c6a0bac4b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -438,7 +438,7 @@ int btrfs_get_extent_inline_ref_type(const struct extent_buffer *eb, return BTRFS_REF_TYPE_INVALID; } -static u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset) +u64 hash_extent_data_ref(u64 root_objectid, u64 owner, u64 offset) { u32 high_crc = ~(u32)0; u32 low_crc = ~(u32)0; diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index 0a56616bef9a..9645389a1187 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -1187,6 +1187,51 @@ static int check_simple_keyed_refs(struct extent_buffer *leaf, return 0; } +static int check_extent_data_ref(struct extent_buffer *leaf, + struct btrfs_key *key, int slot) +{ + struct btrfs_extent_data_ref *dref; + unsigned long ptr = btrfs_item_ptr_offset(leaf, slot); + const unsigned long end = ptr + btrfs_item_size_nr(leaf, slot); + + if (btrfs_item_size_nr(leaf, slot) % sizeof(*dref) != 0) { + generic_err(leaf, slot, + "invalid item size, have %u expect aligned to %zu for key type %u", + btrfs_item_size_nr(leaf, slot), + sizeof(*dref), key->type); + } + if (!IS_ALIGNED(key->objectid, leaf->fs_info->sectorsize)) { + generic_err(leaf, slot, +"invalid key objectid for shared block ref, have %llu expect aligned to %u", + key->objectid, leaf->fs_info->sectorsize); + return -EUCLEAN; + } + for (; ptr < end; ptr += sizeof(*dref)) { + u64 root_objectid; + u64 owner; + u64 offset; + u64 hash; + + dref = (struct btrfs_extent_data_ref *)ptr; + root_objectid = btrfs_extent_data_ref_root(leaf, dref); + owner = btrfs_extent_data_ref_objectid(leaf, dref); + offset = btrfs_extent_data_ref_offset(leaf, dref); + hash = hash_extent_data_ref(root_objectid, owner, offset); + if (hash != key->offset) { + extent_err(leaf, slot, + "invalid extent data ref hash, item has 0x%016llx key has 0x%016llx", + hash, key->offset); + return -EUCLEAN; + } + if (!IS_ALIGNED(offset, leaf->fs_info->sectorsize)) { + extent_err(leaf, slot, + "invalid extent data backref offset, have %llu expect aligned to %u", + offset, leaf->fs_info->sectorsize); + } + } + return 0; +} + /* * Common point to switch the item-specific validation. */ @@ -1234,6 +1279,9 @@ static int check_leaf_item(struct extent_buffer *leaf, case BTRFS_SHARED_BLOCK_REF_KEY: ret = check_simple_keyed_refs(leaf, key, slot); break; + case BTRFS_EXTENT_DATA_REF_KEY: + ret = check_extent_data_ref(leaf, key, slot); + break; } return ret; }