Commit 72ea15f0 authored by Eric Biggers's avatar Eric Biggers
Browse files

fsverity: pass pos and size to ->write_merkle_tree_block 



fsverity_operations::write_merkle_tree_block is passed the index of the
block to write and the log base 2 of the block size.  However, all
implementations of it use these parameters only to calculate the
position and the size of the block, in bytes.

Therefore, make ->write_merkle_tree_block take 'pos' and 'size'
parameters instead of 'index' and 'log_blocksize'.

Suggested-by: default avatarDave Chinner <david@fromorbit.com>
Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
Acked-by: default avatarDave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20221214224304.145712-5-ebiggers@kernel.org
parent 9642946c

fs/btrfs/verity.c

+7 −12
Original line number Diff line number Diff line
@@ -784,29 +784,24 @@ static struct page *btrfs_read_merkle_tree_page(struct inode *inode, 
 * fsverity op that writes a Merkle tree block into the btree.

 *

 * @inode:	inode to write a Merkle tree block for

 * @buf:            Merkle tree data block to write

 * @index:          index of the block in the Merkle tree

 * @log_blocksize:  log base 2 of the Merkle tree block size

 *

 * Note that the block size could be different from the page size, so it is not

 * safe to assume that index is a page index.

 * @buf:	Merkle tree block to write

 * @pos:	the position of the block in the Merkle tree (in bytes)

 * @size:	the Merkle tree block size (in bytes)

 *

 * Returns 0 on success or negative error code on failure

 */

static int btrfs_write_merkle_tree_block(struct inode *inode, const void *buf,

					u64 index, int log_blocksize)

					 u64 pos, unsigned int size)

{

	u64 off = index << log_blocksize;

	u64 len = 1ULL << log_blocksize;

	loff_t merkle_pos = merkle_file_pos(inode);



	if (merkle_pos < 0)

		return merkle_pos;

	if (merkle_pos > inode->i_sb->s_maxbytes - off - len)

	if (merkle_pos > inode->i_sb->s_maxbytes - pos - size)

		return -EFBIG;



	return write_key_bytes(BTRFS_I(inode), BTRFS_VERITY_MERKLE_ITEM_KEY,

			       off, buf, len);

			       pos, buf, size);

}



const struct fsverity_operations btrfs_verityops = {

fs/ext4/verity.c

+3 −3
Original line number Diff line number Diff line
@@ -381,11 +381,11 @@ static struct page *ext4_read_merkle_tree_page(struct inode *inode, 
}



static int ext4_write_merkle_tree_block(struct inode *inode, const void *buf,

					u64 index, int log_blocksize)

					u64 pos, unsigned int size)

{

	loff_t pos = ext4_verity_metadata_pos(inode) + (index << log_blocksize);

	pos += ext4_verity_metadata_pos(inode);



	return pagecache_write(inode, buf, 1 << log_blocksize, pos);

	return pagecache_write(inode, buf, size, pos);

}



const struct fsverity_operations ext4_verityops = {

fs/f2fs/verity.c

+3 −3
Original line number Diff line number Diff line
@@ -276,11 +276,11 @@ static struct page *f2fs_read_merkle_tree_page(struct inode *inode, 
}



static int f2fs_write_merkle_tree_block(struct inode *inode, const void *buf,

					u64 index, int log_blocksize)

					u64 pos, unsigned int size)

{

	loff_t pos = f2fs_verity_metadata_pos(inode) + (index << log_blocksize);

	pos += f2fs_verity_metadata_pos(inode);



	return pagecache_write(inode, buf, 1 << log_blocksize, pos);

	return pagecache_write(inode, buf, size, pos);

}



const struct fsverity_operations f2fs_verityops = {

fs/verity/enable.c

+2 −2
Original line number Diff line number Diff line
@@ -120,8 +120,8 @@ static int build_merkle_tree_level(struct file *filp, unsigned int level, 
			       params->block_size - pending_size);

			err = vops->write_merkle_tree_block(inode,

					pending_hashes,

					dst_block_num,

					params->log_blocksize);

					dst_block_num << params->log_blocksize,

					params->block_size);

			if (err) {

				fsverity_err(inode,

					     "Error %d writing Merkle tree block %llu",

include/linux/fsverity.h

+4 −4
Original line number Diff line number Diff line
@@ -109,9 +109,9 @@ struct fsverity_operations { 
	 * Write a Merkle tree block to the given inode.

	 *

	 * @inode: the inode for which the Merkle tree is being built

	 * @buf: block to write

	 * @index: 0-based index of the block within the Merkle tree

	 * @log_blocksize: log base 2 of the Merkle tree block size

	 * @buf: the Merkle tree block to write

	 * @pos: the position of the block in the Merkle tree (in bytes)

	 * @size: the Merkle tree block size (in bytes)

	 *

	 * This is only called between ->begin_enable_verity() and

	 * ->end_enable_verity().
@@ -119,7 +119,7 @@ struct fsverity_operations { 
	 * Return: 0 on success, -errno on failure

	 */

	int (*write_merkle_tree_block)(struct inode *inode, const void *buf,

				       u64 index, int log_blocksize);

				       u64 pos, unsigned int size);

};



#ifdef CONFIG_FS_VERITY