4.9-stable review patch. If anyone has any objections, please let me know.
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From: Qu Wenruo quwenruo.btrfs@gmx.com
commit 4b865cab96fe2a30ed512cf667b354bd291b3b0a upstream.
EXTENT_CSUM checker is a relatively easy one, only needs to check:
1) Objectid Fixed to BTRFS_EXTENT_CSUM_OBJECTID
2) Key offset alignment Must be aligned to sectorsize
3) Item size alignedment Must be aligned to csum size
Signed-off-by: Qu Wenruo quwenruo.btrfs@gmx.com Reviewed-by: Nikolay Borisov nborisov@suse.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com [bwh: Backported to 4.9: Use root->sectorsize instead of root->fs_info->sectorsize] Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/disk-io.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
--- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -621,6 +621,27 @@ static int check_extent_data_item(struct return 0; }
+static int check_csum_item(struct btrfs_root *root, struct extent_buffer *leaf, + struct btrfs_key *key, int slot) +{ + u32 sectorsize = root->sectorsize; + u32 csumsize = btrfs_super_csum_size(root->fs_info->super_copy); + + if (key->objectid != BTRFS_EXTENT_CSUM_OBJECTID) { + CORRUPT("invalid objectid for csum item", leaf, root, slot); + return -EUCLEAN; + } + if (!IS_ALIGNED(key->offset, sectorsize)) { + CORRUPT("unaligned key offset for csum item", leaf, root, slot); + return -EUCLEAN; + } + if (!IS_ALIGNED(btrfs_item_size_nr(leaf, slot), csumsize)) { + CORRUPT("unaligned csum item size", leaf, root, slot); + return -EUCLEAN; + } + return 0; +} + /* * Common point to switch the item-specific validation. */ @@ -634,6 +655,9 @@ static int check_leaf_item(struct btrfs_ case BTRFS_EXTENT_DATA_KEY: ret = check_extent_data_item(root, leaf, key, slot); break; + case BTRFS_EXTENT_CSUM_KEY: + ret = check_csum_item(root, leaf, key, slot); + break; } return ret; }