3 files changed, 296 insertions, 98 deletions

diff --git a/fs/verity/fsverity_private.h b/fs/verity/fsverity_private.h
index 23ded939d649..d34dcc033d72 100644
--- a/fs/verity/fsverity_private.h
+++ b/fs/verity/fsverity_private.h
@@ -42,9 +42,11 @@ struct merkle_tree_params {
 	unsigned int digest_size;	/* same as hash_alg->digest_size */
 	unsigned int block_size;	/* size of data and tree blocks */
 	unsigned int hashes_per_block;	/* number of hashes per tree block */
+	unsigned int blocks_per_page;	/* PAGE_SIZE / block_size */
 	u8 log_digestsize;		/* log2(digest_size) */
 	u8 log_blocksize;		/* log2(block_size) */
 	u8 log_arity;			/* log2(hashes_per_block) */
+	u8 log_blocks_per_page;		/* log2(blocks_per_page) */
 	unsigned int num_levels;	/* number of levels in Merkle tree */
 	u64 tree_size;			/* Merkle tree size in bytes */
 	unsigned long tree_pages;	/* Merkle tree size in pages */
@@ -70,9 +72,10 @@ struct fsverity_info {
 	u8 root_hash[FS_VERITY_MAX_DIGEST_SIZE];
 	u8 file_digest[FS_VERITY_MAX_DIGEST_SIZE];
 	const struct inode *inode;
+	unsigned long *hash_block_verified;
+	spinlock_t hash_page_init_lock;
 };
 
-
 #define FS_VERITY_MAX_SIGNATURE_SIZE	(FS_VERITY_MAX_DESCRIPTOR_SIZE - \
 					 sizeof(struct fsverity_descriptor))
 
diff --git a/fs/verity/open.c b/fs/verity/open.c
index 09512daa22db..9366b441d01c 100644
--- a/fs/verity/open.c
+++ b/fs/verity/open.c
@@ -56,7 +56,23 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params,
 		goto out_err;
 	}
 
-	if (log_blocksize != PAGE_SHIFT) {
+	/*
+	 * fs/verity/ directly assumes that the Merkle tree block size is a
+	 * power of 2 less than or equal to PAGE_SIZE.  Another restriction
+	 * arises from the interaction between fs/verity/ and the filesystems
+	 * themselves: filesystems expect to be able to verify a single
+	 * filesystem block of data at a time.  Therefore, the Merkle tree block
+	 * size must also be less than or equal to the filesystem block size.
+	 *
+	 * The above are the only hard limitations, so in theory the Merkle tree
+	 * block size could be as small as twice the digest size.  However,
+	 * that's not useful, and it would result in some unusually deep and
+	 * large Merkle trees.  So we currently require that the Merkle tree
+	 * block size be at least 1024 bytes.  That's small enough to test the
+	 * sub-page block case on systems with 4K pages, but not too small.
+	 */
+	if (log_blocksize < 10 || log_blocksize > PAGE_SHIFT ||
+	    log_blocksize > inode->i_blkbits) {
 		fsverity_warn(inode, "Unsupported log_blocksize: %u",
 			      log_blocksize);
 		err = -EINVAL;
@@ -64,6 +80,8 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params,
 	}
 	params->log_blocksize = log_blocksize;
 	params->block_size = 1 << log_blocksize;
+	params->log_blocks_per_page = PAGE_SHIFT - log_blocksize;
+	params->blocks_per_page = 1 << params->log_blocks_per_page;
 
 	if (WARN_ON(!is_power_of_2(params->digest_size))) {
 		err = -EINVAL;
@@ -108,11 +126,19 @@ int fsverity_init_merkle_tree_params(struct merkle_tree_params *params,
 	}
 
 	/*
-	 * Since the data, and thus also the Merkle tree, cannot have more than
-	 * ULONG_MAX pages, hash block indices can always fit in an
-	 * 'unsigned long'.  To be safe, explicitly check for it too.
+	 * With block_size != PAGE_SIZE, an in-memory bitmap will need to be
+	 * allocated to track the "verified" status of hash blocks.  Don't allow
+	 * this bitmap to get too large.  For now, limit it to 1 MiB, which
+	 * limits the file size to about 4.4 TB with SHA-256 and 4K blocks.
+	 *
+	 * Together with the fact that the data, and thus also the Merkle tree,
+	 * cannot have more than ULONG_MAX pages, this implies that hash block
+	 * indices can always fit in an 'unsigned long'.  But to be safe, we
+	 * explicitly check for that too.  Note, this is only for hash block
+	 * indices; data block indices might not fit in an 'unsigned long'.
 	 */
-	if (offset > ULONG_MAX) {
+	if ((params->block_size != PAGE_SIZE && offset > 1 << 23) ||
+	    offset > ULONG_MAX) {
 		fsverity_err(inode, "Too many blocks in Merkle tree");
 		err = -EFBIG;
 		goto out_err;
@@ -170,7 +196,7 @@ struct fsverity_info *fsverity_create_info(const struct inode *inode,
 		fsverity_err(inode,
 			     "Error %d initializing Merkle tree parameters",
 			     err);
-		goto out;
+		goto fail;
 	}
 
 	memcpy(vi->root_hash, desc->root_hash, vi->tree_params.digest_size);
@@ -179,17 +205,48 @@ struct fsverity_info *fsverity_create_info(const struct inode *inode,
 				  vi->file_digest);
 	if (err) {
 		fsverity_err(inode, "Error %d computing file digest", err);
-		goto out;
+		goto fail;
 	}
 
 	err = fsverity_verify_signature(vi, desc->signature,
 					le32_to_cpu(desc->sig_size));
-out:
-	if (err) {
-		fsverity_free_info(vi);
-		vi = ERR_PTR(err);
+	if (err)
+		goto fail;
+
+	if (vi->tree_params.block_size != PAGE_SIZE) {
+		/*
+		 * When the Merkle tree block size and page size differ, we use
+		 * a bitmap to keep track of which hash blocks have been
+		 * verified.  This bitmap must contain one bit per hash block,
+		 * including alignment to a page boundary at the end.
+		 *
+		 * Eventually, to support extremely large files in an efficient
+		 * way, it might be necessary to make pages of this bitmap
+		 * reclaimable.  But for now, simply allocating the whole bitmap
+		 * is a simple solution that works well on the files on which
+		 * fsverity is realistically used.  E.g., with SHA-256 and 4K
+		 * blocks, a 100MB file only needs a 24-byte bitmap, and the
+		 * bitmap for any file under 17GB fits in a 4K page.
+		 */
+		unsigned long num_bits =
+			vi->tree_params.tree_pages <<
+			vi->tree_params.log_blocks_per_page;
+
+		vi->hash_block_verified = kvcalloc(BITS_TO_LONGS(num_bits),
+						   sizeof(unsigned long),
+						   GFP_KERNEL);
+		if (!vi->hash_block_verified) {
+			err = -ENOMEM;
+			goto fail;
+		}
+		spin_lock_init(&vi->hash_page_init_lock);
 	}
+
 	return vi;
+
+fail:
+	fsverity_free_info(vi);
+	return ERR_PTR(err);
 }
 
 void fsverity_set_info(struct inode *inode, struct fsverity_info *vi)
@@ -216,6 +273,7 @@ void fsverity_free_info(struct fsverity_info *vi)
 	if (!vi)
 		return;
 	kfree(vi->tree_params.hashstate);
+	kvfree(vi->hash_block_verified);
 	kmem_cache_free(fsverity_info_cachep, vi);
 }
 
diff --git a/fs/verity/verify.c b/fs/verity/verify.c
index 44df06ddcc60..e59ef9d0e21c 100644
--- a/fs/verity/verify.c
+++ b/fs/verity/verify.c
@@ -12,35 +12,9 @@
 
 static struct workqueue_struct *fsverity_read_workqueue;
 
-/**
- * hash_at_level() - compute the location of the block's hash at the given level
- *
- * @params:	(in) the Merkle tree parameters
- * @dindex:	(in) the index of the data block being verified
- * @level:	(in) the level of hash we want (0 is leaf level)
- * @hindex:	(out) the index of the hash block containing the wanted hash
- * @hoffset:	(out) the byte offset to the wanted hash within the hash block
- */
-static void hash_at_level(const struct merkle_tree_params *params,
-			  pgoff_t dindex, unsigned int level, pgoff_t *hindex,
-			  unsigned int *hoffset)
-{
-	pgoff_t position;
-
-	/* Offset of the hash within the level's region, in hashes */
-	position = dindex >> (level * params->log_arity);
-
-	/* Index of the hash block in the tree overall */
-	*hindex = params->level_start[level] + (position >> params->log_arity);
-
-	/* Offset of the wanted hash (in bytes) within the hash block */
-	*hoffset = (position & ((1 << params->log_arity) - 1)) <<
-		   params->log_digestsize;
-}
-
 static inline int cmp_hashes(const struct fsverity_info *vi,
 			     const u8 *want_hash, const u8 *real_hash,
-			     pgoff_t index, int level)
+			     u64 data_pos, int level)
 {
 	const unsigned int hsize = vi->tree_params.digest_size;
 
@@ -48,148 +22,310 @@ static inline int cmp_hashes(const struct fsverity_info *vi,
 		return 0;
 
 	fsverity_err(vi->inode,
-		     "FILE CORRUPTED! index=%lu, level=%d, want_hash=%s:%*phN, real_hash=%s:%*phN",
-		     index, level,
+		     "FILE CORRUPTED! pos=%llu, level=%d, want_hash=%s:%*phN, real_hash=%s:%*phN",
+		     data_pos, level,
 		     vi->tree_params.hash_alg->name, hsize, want_hash,
 		     vi->tree_params.hash_alg->name, hsize, real_hash);
 	return -EBADMSG;
 }
 
+static bool data_is_zeroed(struct inode *inode, struct page *page,
+			   unsigned int len, unsigned int offset)
+{
+	void *virt = kmap_local_page(page);
+
+	if (memchr_inv(virt + offset, 0, len)) {
+		kunmap_local(virt);
+		fsverity_err(inode,
+			     "FILE CORRUPTED!  Data past EOF is not zeroed");
+		return false;
+	}
+	kunmap_local(virt);
+	return true;
+}
+
+/*
+ * Returns true if the hash block with index @hblock_idx in the tree, located in
+ * @hpage, has already been verified.
+ */
+static bool is_hash_block_verified(struct fsverity_info *vi, struct page *hpage,
+				   unsigned long hblock_idx)
+{
+	bool verified;
+	unsigned int blocks_per_page;
+	unsigned int i;
+
+	/*
+	 * When the Merkle tree block size and page size are the same, then the
+	 * ->hash_block_verified bitmap isn't allocated, and we use PG_checked
+	 * to directly indicate whether the page's block has been verified.
+	 *
+	 * Using PG_checked also guarantees that we re-verify hash pages that
+	 * get evicted and re-instantiated from the backing storage, as new
+	 * pages always start out with PG_checked cleared.
+	 */
+	if (!vi->hash_block_verified)
+		return PageChecked(hpage);
+
+	/*
+	 * When the Merkle tree block size and page size differ, we use a bitmap
+	 * to indicate whether each hash block has been verified.
+	 *
+	 * However, we still need to ensure that hash pages that get evicted and
+	 * re-instantiated from the backing storage are re-verified.  To do
+	 * this, we use PG_checked again, but now it doesn't really mean
+	 * "checked".  Instead, now it just serves as an indicator for whether
+	 * the hash page is newly instantiated or not.
+	 *
+	 * The first thread that sees PG_checked=0 must clear the corresponding
+	 * bitmap bits, then set PG_checked=1.  This requires a spinlock.  To
+	 * avoid having to take this spinlock in the common case of
+	 * PG_checked=1, we start with an opportunistic lockless read.
+	 */
+	if (PageChecked(hpage)) {
+		/*
+		 * A read memory barrier is needed here to give ACQUIRE
+		 * semantics to the above PageChecked() test.
+		 */
+		smp_rmb();
+		return test_bit(hblock_idx, vi->hash_block_verified);
+	}
+	spin_lock(&vi->hash_page_init_lock);
+	if (PageChecked(hpage)) {
+		verified = test_bit(hblock_idx, vi->hash_block_verified);
+	} else {
+		blocks_per_page = vi->tree_params.blocks_per_page;
+		hblock_idx = round_down(hblock_idx, blocks_per_page);
+		for (i = 0; i < blocks_per_page; i++)
+			clear_bit(hblock_idx + i, vi->hash_block_verified);
+		/*
+		 * A write memory barrier is needed here to give RELEASE
+		 * semantics to the below SetPageChecked() operation.
+		 */
+		smp_wmb();
+		SetPageChecked(hpage);
+		verified = false;
+	}
+	spin_unlock(&vi->hash_page_init_lock);
+	return verified;
+}
+
 /*
- * Verify a single data page against the file's Merkle tree.
+ * Verify a single data block against the file's Merkle tree.
  *
  * In principle, we need to verify the entire path to the root node.  However,
- * for efficiency the filesystem may cache the hash pages.  Therefore we need
- * only ascend the tree until an already-verified page is seen, as indicated by
- * the PageChecked bit being set; then verify the path to that page.
+ * for efficiency the filesystem may cache the hash blocks.  Therefore we need
+ * only ascend the tree until an already-verified hash block is seen, and then
+ * verify the path to that block.
  *
- * This code currently only supports the case where the verity block size is
- * equal to PAGE_SIZE.  Doing otherwise would be possible but tricky, since we
- * wouldn't be able to use the PageChecked bit.
- *
- * Note that multiple processes may race to verify a hash page and mark it
- * Checked, but it doesn't matter; the result will be the same either way.
- *
- * Return: true if the page is valid, else false.
+ * Return: %true if the data block is valid, else %false.
  */
-static bool verify_page(struct inode *inode, const struct fsverity_info *vi,
-			struct ahash_request *req, struct page *data_page,
-			unsigned long max_ra_pages)
+static bool
+verify_data_block(struct inode *inode, struct fsverity_info *vi,
+		  struct ahash_request *req, struct page *data_page,
+		  u64 data_pos, unsigned int dblock_offset_in_page,
+		  unsigned long max_ra_pages)
 {
 	const struct merkle_tree_params *params = &vi->tree_params;
 	const unsigned int hsize = params->digest_size;
-	const pgoff_t index = data_page->index;
 	int level;
 	u8 _want_hash[FS_VERITY_MAX_DIGEST_SIZE];
 	const u8 *want_hash;
 	u8 real_hash[FS_VERITY_MAX_DIGEST_SIZE];
-	struct page *hpages[FS_VERITY_MAX_LEVELS];
-	unsigned int hoffsets[FS_VERITY_MAX_LEVELS];
+	/* The hash blocks that are traversed, indexed by level */
+	struct {
+		/* Page containing the hash block */
+		struct page *page;
+		/* Index of the hash block in the tree overall */
+		unsigned long index;
+		/* Byte offset of the hash block within @page */
+		unsigned int offset_in_page;
+		/* Byte offset of the wanted hash within @page */
+		unsigned int hoffset;
+	} hblocks[FS_VERITY_MAX_LEVELS];
+	/*
+	 * The index of the previous level's block within that level; also the
+	 * index of that block's hash within the current level.
+	 */
+	u64 hidx = data_pos >> params->log_blocksize;
 	int err;
 
-	if (WARN_ON_ONCE(!PageLocked(data_page) || PageUptodate(data_page)))
-		return false;
+	if (unlikely(data_pos >= inode->i_size)) {
+		/*
+		 * This can happen in the data page spanning EOF when the Merkle
+		 * tree block size is less than the page size.  The Merkle tree
+		 * doesn't cover data blocks fully past EOF.  But the entire
+		 * page spanning EOF can be visible to userspace via a mmap, and
+		 * any part past EOF should be all zeroes.  Therefore, we need
+		 * to verify that any data blocks fully past EOF are all zeroes.
+		 */
+		return data_is_zeroed(inode, data_page, params->block_size,
+				      dblock_offset_in_page);
+	}
 
 	/*
-	 * Starting at the leaf level, ascend the tree saving hash pages along
-	 * the way until we find a verified hash page, indicated by PageChecked;
-	 * or until we reach the root.
+	 * Starting at the leaf level, ascend the tree saving hash blocks along
+	 * the way until we find a hash block that has already been verified, or
+	 * until we reach the root.
 	 */
 	for (level = 0; level < params->num_levels; level++) {
-		pgoff_t hindex;
+		unsigned long next_hidx;
+		unsigned long hblock_idx;
+		pgoff_t hpage_idx;
+		unsigned int hblock_offset_in_page;
 		unsigned int hoffset;
 		struct page *hpage;
 
-		hash_at_level(params, index, level, &hindex, &hoffset);
+		/*
+		 * The index of the block in the current level; also the index
+		 * of that block's hash within the next level.
+		 */
+		next_hidx = hidx >> params->log_arity;
+
+		/* Index of the hash block in the tree overall */
+		hblock_idx = params->level_start[level] + next_hidx;
+
+		/* Index of the hash page in the tree overall */
+		hpage_idx = hblock_idx >> params->log_blocks_per_page;
+
+		/* Byte offset of the hash block within the page */
+		hblock_offset_in_page =
+			(hblock_idx << params->log_blocksize) & ~PAGE_MASK;
+
+		/* Byte offset of the hash within the page */
+		hoffset = hblock_offset_in_page +
+			  ((hidx << params->log_digestsize) &
+			   (params->block_size - 1));
 
-		hpage = inode->i_sb->s_vop->read_merkle_tree_page(inode, hindex,
-				level == 0 ? min(max_ra_pages,
-					params->tree_pages - hindex) : 0);
+		hpage = inode->i_sb->s_vop->read_merkle_tree_page(inode,
+				hpage_idx, level == 0 ? min(max_ra_pages,
+					params->tree_pages - hpage_idx) : 0);
 		if (IS_ERR(hpage)) {
 			err = PTR_ERR(hpage);
 			fsverity_err(inode,
 				     "Error %d reading Merkle tree page %lu",
-				     err, hindex);
+				     err, hpage_idx);
 			goto out;
 		}
-
-		if (PageChecked(hpage)) {
+		if (is_hash_block_verified(vi, hpage, hblock_idx)) {
 			memcpy_from_page(_want_hash, hpage, hoffset, hsize);
 			want_hash = _want_hash;
 			put_page(hpage);
 			goto descend;
 		}
-		hpages[level] = hpage;
-		hoffsets[level] = hoffset;
+		hblocks[level].page = hpage;
+		hblocks[level].index = hblock_idx;
+		hblocks[level].offset_in_page = hblock_offset_in_page;
+		hblocks[level].hoffset = hoffset;
+		hidx = next_hidx;
 	}
 
 	want_hash = vi->root_hash;
 descend:
 	/* Descend the tree verifying hash blocks. */
 	for (; level > 0; level--) {
-		struct page *hpage = hpages[level - 1];
-		unsigned int hoffset = hoffsets[level - 1];
-
-		err = fsverity_hash_block(params, inode, req, hpage, 0,
-					  real_hash);
+		struct page *hpage = hblocks[level - 1].page;
+		unsigned long hblock_idx = hblocks[level - 1].index;
+		unsigned int hblock_offset_in_page =
+			hblocks[level - 1].offset_in_page;
+		unsigned int hoffset = hblocks[level - 1].hoffset;
+
+		err = fsverity_hash_block(params, inode, req, hpage,
+					  hblock_offset_in_page, real_hash);
 		if (err)
 			goto out;
-		err = cmp_hashes(vi, want_hash, real_hash, index, level - 1);
+		err = cmp_hashes(vi, want_hash, real_hash, data_pos, level - 1);
 		if (err)
 			goto out;
-		SetPageChecked(hpage);
+		/*
+		 * Mark the hash block as verified.  This must be atomic and
+		 * idempotent, as the same hash block might be verified by
+		 * multiple threads concurrently.
+		 */
+		if (vi->hash_block_verified)
+			set_bit(hblock_idx, vi->hash_block_verified);
+		else
+			SetPageChecked(hpage);
 		memcpy_from_page(_want_hash, hpage, hoffset, hsize);
 		want_hash = _want_hash;
 		put_page(hpage);
 	}
 
 	/* Finally, verify the data block. */
-	err = fsverity_hash_block(params, inode, req, data_page, 0, real_hash);
+	err = fsverity_hash_block(params, inode, req, data_page,
+				  dblock_offset_in_page, real_hash);
 	if (err)
 		goto out;
-	err = cmp_hashes(vi, want_hash, real_hash, index, -1);
+	err = cmp_hashes(vi, want_hash, real_hash, data_pos, -1);
 out:
 	for (; level > 0; level--)
-		put_page(hpages[level - 1]);
+		put_page(hblocks[level - 1].page);
 
 	return err == 0;
 }
 
+static bool
+verify_data_blocks(struct inode *inode, struct fsverity_info *vi,
+		   struct ahash_request *req, struct page *data_page,
+		   unsigned int len, unsigned int offset,
+		   unsigned long max_ra_pages)
+{
+	const unsigned int block_size = vi->tree_params.block_size;
+	u64 pos = (u64)data_page->index << PAGE_SHIFT;
+
+	if (WARN_ON_ONCE(len <= 0 || !IS_ALIGNED(len | offset, block_size)))
+		return false;
+	if (WARN_ON_ONCE(!PageLocked(data_page) || PageUptodate(data_page)))
+		return false;
+	do {
+		if (!verify_data_block(inode, vi, req, data_page,
+				       pos + offset, offset, max_ra_pages))
+			return false;
+		offset += block_size;
+		len -= block_size;
+	} while (len);
+	return true;
+}
+
 /**
- * fsverity_verify_page() - verify a data page
- * @page: the page to verity
+ * fsverity_verify_blocks() - verify data in a page
+ * @page: the page containing the data to verify
+ * @len: the length of the data to verify in the page
+ * @offset: the offset of the data to verify in the page
  *
- * Verify a page that has just been read from a verity file.  The page must be a
- * pagecache page that is still locked and not yet uptodate.
+ * Verify data that has just been read from a verity file.  The data must be
+ * located in a pagecache page that is still locked and not yet uptodate.  The
+ * length and offset of the data must be Merkle tree block size aligned.
  *
- * Return: true if the page is valid, else false.
+ * Return: %true if the data is valid, else %false.
  */
-bool fsverity_verify_page(struct page *page)
+bool fsverity_verify_blocks(struct page *page, unsigned int len,
+			    unsigned int offset)
 {
 	struct inode *inode = page->mapping->host;
-	const struct fsverity_info *vi = inode->i_verity_info;
+	struct fsverity_info *vi = inode->i_verity_info;
 	struct ahash_request *req;
 	bool valid;
 
 	/* This allocation never fails, since it's mempool-backed. */
 	req = fsverity_alloc_hash_request(vi->tree_params.hash_alg, GFP_NOFS);
 
-	valid = verify_page(inode, vi, req, page, 0);
+	valid = verify_data_blocks(inode, vi, req, page, len, offset, 0);
 
 	fsverity_free_hash_request(vi->tree_params.hash_alg, req);
 
 	return valid;
 }
-EXPORT_SYMBOL_GPL(fsverity_verify_page);
+EXPORT_SYMBOL_GPL(fsverity_verify_blocks);
 
 #ifdef CONFIG_BLOCK
 /**
  * fsverity_verify_bio() - verify a 'read' bio that has just completed
  * @bio: the bio to verify
  *
- * Verify a set of pages that have just been read from a verity file.  The pages
- * must be pagecache pages that are still locked and not yet uptodate.  If a
- * page fails verification, then bio->bi_status is set to an error status.
+ * Verify the bio's data against the file's Merkle tree.  All bio data segments
+ * must be aligned to the file's Merkle tree block size.  If any data fails
+ * verification, then bio->bi_status is set to an error status.
  *
  * This is a helper function for use by the ->readahead() method of filesystems
  * that issue bios to read data directly into the page cache.  Filesystems that
@@ -200,7 +336,7 @@ EXPORT_SYMBOL_GPL(fsverity_verify_page);
 void fsverity_verify_bio(struct bio *bio)
 {
 	struct inode *inode = bio_first_page_all(bio)->mapping->host;
-	const struct fsverity_info *vi = inode->i_verity_info;
+	struct fsverity_info *vi = inode->i_verity_info;
 	struct ahash_request *req;
 	struct bio_vec *bv;
 	struct bvec_iter_all iter_all;
@@ -223,7 +359,8 @@ void fsverity_verify_bio(struct bio *bio)
 	}
 
 	bio_for_each_segment_all(bv, bio, iter_all) {
-		if (!verify_page(inode, vi, req, bv->bv_page, max_ra_pages)) {
+		if (!verify_data_blocks(inode, vi, req, bv->bv_page, bv->bv_len,
+					bv->bv_offset, max_ra_pages)) {
 			bio->bi_status = BLK_STS_IOERR;
 			break;
 		}