Fixed MTP to work with TWRP

fs/hfsplus/xattr.c

@@ -0,0 +1,865 @@
+/*
+ * linux/fs/hfsplus/xattr.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Logic of processing extended attributes
+ */
+
+#include "hfsplus_fs.h"
+#include <linux/posix_acl_xattr.h>
+#include <linux/nls.h>
+#include "xattr.h"
+#include "acl.h"
+
+static int hfsplus_removexattr(struct inode *inode, const char *name);
+
+const struct xattr_handler *hfsplus_xattr_handlers[] = {
+	&hfsplus_xattr_osx_handler,
+	&hfsplus_xattr_user_handler,
+	&hfsplus_xattr_trusted_handler,
+#ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
+	&posix_acl_access_xattr_handler,
+	&posix_acl_default_xattr_handler,
+#endif
+	&hfsplus_xattr_security_handler,
+	NULL
+};
+
+static int strcmp_xattr_finder_info(const char *name)
+{
+	if (name) {
+		return strncmp(name, HFSPLUS_XATTR_FINDER_INFO_NAME,
+				sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME));
+	}
+	return -1;
+}
+
+static int strcmp_xattr_acl(const char *name)
+{
+	if (name) {
+		return strncmp(name, HFSPLUS_XATTR_ACL_NAME,
+				sizeof(HFSPLUS_XATTR_ACL_NAME));
+	}
+	return -1;
+}
+
+static inline int is_known_namespace(const char *name)
+{
+	if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
+	    strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
+	    strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
+	    strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
+		return false;
+
+	return true;
+}
+
+static void hfsplus_init_header_node(struct inode *attr_file,
+					u32 clump_size,
+					char *buf, u16 node_size)
+{
+	struct hfs_bnode_desc *desc;
+	struct hfs_btree_header_rec *head;
+	u16 offset;
+	__be16 *rec_offsets;
+	u32 hdr_node_map_rec_bits;
+	char *bmp;
+	u32 used_nodes;
+	u32 used_bmp_bytes;
+	u64 tmp;
+
+	hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %u\n",
+		clump_size, node_size);
+
+	/* The end of the node contains list of record offsets */
+	rec_offsets = (__be16 *)(buf + node_size);
+
+	desc = (struct hfs_bnode_desc *)buf;
+	desc->type = HFS_NODE_HEADER;
+	desc->num_recs = cpu_to_be16(HFSPLUS_BTREE_HDR_NODE_RECS_COUNT);
+	offset = sizeof(struct hfs_bnode_desc);
+	*--rec_offsets = cpu_to_be16(offset);
+
+	head = (struct hfs_btree_header_rec *)(buf + offset);
+	head->node_size = cpu_to_be16(node_size);
+	tmp = i_size_read(attr_file);
+	do_div(tmp, node_size);
+	head->node_count = cpu_to_be32(tmp);
+	head->free_nodes = cpu_to_be32(be32_to_cpu(head->node_count) - 1);
+	head->clump_size = cpu_to_be32(clump_size);
+	head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);
+	head->max_key_len = cpu_to_be16(HFSPLUS_ATTR_KEYLEN - sizeof(u16));
+	offset += sizeof(struct hfs_btree_header_rec);
+	*--rec_offsets = cpu_to_be16(offset);
+	offset += HFSPLUS_BTREE_HDR_USER_BYTES;
+	*--rec_offsets = cpu_to_be16(offset);
+
+	hdr_node_map_rec_bits = 8 * (node_size - offset - (4 * sizeof(u16)));
+	if (be32_to_cpu(head->node_count) > hdr_node_map_rec_bits) {
+		u32 map_node_bits;
+		u32 map_nodes;
+
+		desc->next = cpu_to_be32(be32_to_cpu(head->leaf_tail) + 1);
+		map_node_bits = 8 * (node_size - sizeof(struct hfs_bnode_desc) -
+					(2 * sizeof(u16)) - 2);
+		map_nodes = (be32_to_cpu(head->node_count) -
+				hdr_node_map_rec_bits +
+				(map_node_bits - 1)) / map_node_bits;
+		be32_add_cpu(&head->free_nodes, 0 - map_nodes);
+	}
+
+	bmp = buf + offset;
+	used_nodes =
+		be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
+	used_bmp_bytes = used_nodes / 8;
+	if (used_bmp_bytes) {
+		memset(bmp, 0xFF, used_bmp_bytes);
+		bmp += used_bmp_bytes;
+		used_nodes %= 8;
+	}
+	*bmp = ~(0xFF >> used_nodes);
+	offset += hdr_node_map_rec_bits / 8;
+	*--rec_offsets = cpu_to_be16(offset);
+}
+
+static int hfsplus_create_attributes_file(struct super_block *sb)
+{
+	int err = 0;
+	struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
+	struct inode *attr_file;
+	struct hfsplus_inode_info *hip;
+	u32 clump_size;
+	u16 node_size = HFSPLUS_ATTR_TREE_NODE_SIZE;
+	char *buf;
+	int index, written;
+	struct address_space *mapping;
+	struct page *page;
+	int old_state = HFSPLUS_EMPTY_ATTR_TREE;
+
+	hfs_dbg(ATTR_MOD, "create_attr_file: ino %d\n", HFSPLUS_ATTR_CNID);
+
+check_attr_tree_state_again:
+	switch (atomic_read(&sbi->attr_tree_state)) {
+	case HFSPLUS_EMPTY_ATTR_TREE:
+		if (old_state != atomic_cmpxchg(&sbi->attr_tree_state,
+						old_state,
+						HFSPLUS_CREATING_ATTR_TREE))
+			goto check_attr_tree_state_again;
+		break;
+	case HFSPLUS_CREATING_ATTR_TREE:
+		/*
+		 * This state means that another thread is in process
+		 * of AttributesFile creation. Theoretically, it is
+		 * possible to be here. But really __setxattr() method
+		 * first of all calls hfs_find_init() for lookup in
+		 * B-tree of CatalogFile. This method locks mutex of
+		 * CatalogFile's B-tree. As a result, if some thread
+		 * is inside AttributedFile creation operation then
+		 * another threads will be waiting unlocking of
+		 * CatalogFile's B-tree's mutex. However, if code will
+		 * change then we will return error code (-EAGAIN) from
+		 * here. Really, it means that first try to set of xattr
+		 * fails with error but second attempt will have success.
+		 */
+		return -EAGAIN;
+	case HFSPLUS_VALID_ATTR_TREE:
+		return 0;
+	case HFSPLUS_FAILED_ATTR_TREE:
+		return -EOPNOTSUPP;
+	default:
+		BUG();
+	}
+
+	attr_file = hfsplus_iget(sb, HFSPLUS_ATTR_CNID);
+	if (IS_ERR(attr_file)) {
+		pr_err("failed to load attributes file\n");
+		return PTR_ERR(attr_file);
+	}
+
+	BUG_ON(i_size_read(attr_file) != 0);
+
+	hip = HFSPLUS_I(attr_file);
+
+	clump_size = hfsplus_calc_btree_clump_size(sb->s_blocksize,
+						    node_size,
+						    sbi->sect_count,
+						    HFSPLUS_ATTR_CNID);
+
+	mutex_lock(&hip->extents_lock);
+	hip->clump_blocks = clump_size >> sbi->alloc_blksz_shift;
+	mutex_unlock(&hip->extents_lock);
+
+	if (sbi->free_blocks <= (hip->clump_blocks << 1)) {
+		err = -ENOSPC;
+		goto end_attr_file_creation;
+	}
+
+	while (hip->alloc_blocks < hip->clump_blocks) {
+		err = hfsplus_file_extend(attr_file, false);
+		if (unlikely(err)) {
+			pr_err("failed to extend attributes file\n");
+			goto end_attr_file_creation;
+		}
+		hip->phys_size = attr_file->i_size =
+			(loff_t)hip->alloc_blocks << sbi->alloc_blksz_shift;
+		hip->fs_blocks = hip->alloc_blocks << sbi->fs_shift;
+		inode_set_bytes(attr_file, attr_file->i_size);
+	}
+
+	buf = kzalloc(node_size, GFP_NOFS);
+	if (!buf) {
+		pr_err("failed to allocate memory for header node\n");
+		err = -ENOMEM;
+		goto end_attr_file_creation;
+	}
+
+	hfsplus_init_header_node(attr_file, clump_size, buf, node_size);
+
+	mapping = attr_file->i_mapping;
+
+	index = 0;
+	written = 0;
+	for (; written < node_size; index++, written += PAGE_CACHE_SIZE) {
+		void *kaddr;
+
+		page = read_mapping_page(mapping, index, NULL);
+		if (IS_ERR(page)) {
+			err = PTR_ERR(page);
+			goto failed_header_node_init;
+		}
+
+		kaddr = kmap_atomic(page);
+		memcpy(kaddr, buf + written,
+			min_t(size_t, PAGE_CACHE_SIZE, node_size - written));
+		kunmap_atomic(kaddr);
+
+		set_page_dirty(page);
+		page_cache_release(page);
+	}
+
+	hfsplus_mark_inode_dirty(attr_file, HFSPLUS_I_ATTR_DIRTY);
+
+	sbi->attr_tree = hfs_btree_open(sb, HFSPLUS_ATTR_CNID);
+	if (!sbi->attr_tree)
+		pr_err("failed to load attributes file\n");
+
+failed_header_node_init:
+	kfree(buf);
+
+end_attr_file_creation:
+	iput(attr_file);
+
+	if (!err)
+		atomic_set(&sbi->attr_tree_state, HFSPLUS_VALID_ATTR_TREE);
+	else if (err == -ENOSPC)
+		atomic_set(&sbi->attr_tree_state, HFSPLUS_EMPTY_ATTR_TREE);
+	else
+		atomic_set(&sbi->attr_tree_state, HFSPLUS_FAILED_ATTR_TREE);
+
+	return err;
+}
+
+int __hfsplus_setxattr(struct inode *inode, const char *name,
+			const void *value, size_t size, int flags)
+{
+	int err = 0;
+	struct hfs_find_data cat_fd;
+	hfsplus_cat_entry entry;
+	u16 cat_entry_flags, cat_entry_type;
+	u16 folder_finderinfo_len = sizeof(struct DInfo) +
+					sizeof(struct DXInfo);
+	u16 file_finderinfo_len = sizeof(struct FInfo) +
+					sizeof(struct FXInfo);
+
+	if ((!S_ISREG(inode->i_mode) &&
+			!S_ISDIR(inode->i_mode)) ||
+				HFSPLUS_IS_RSRC(inode))
+		return -EOPNOTSUPP;
+
+	if (value == NULL)
+		return hfsplus_removexattr(inode, name);
+
+	err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
+	if (err) {
+		pr_err("can't init xattr find struct\n");
+		return err;
+	}
+
+	err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
+	if (err) {
+		pr_err("catalog searching failed\n");
+		goto end_setxattr;
+	}
+
+	if (!strcmp_xattr_finder_info(name)) {
+		if (flags & XATTR_CREATE) {
+			pr_err("xattr exists yet\n");
+			err = -EOPNOTSUPP;
+			goto end_setxattr;
+		}
+		hfs_bnode_read(cat_fd.bnode, &entry, cat_fd.entryoffset,
+					sizeof(hfsplus_cat_entry));
+		if (be16_to_cpu(entry.type) == HFSPLUS_FOLDER) {
+			if (size == folder_finderinfo_len) {
+				memcpy(&entry.folder.user_info, value,
+						folder_finderinfo_len);
+				hfs_bnode_write(cat_fd.bnode, &entry,
+					cat_fd.entryoffset,
+					sizeof(struct hfsplus_cat_folder));
+				hfsplus_mark_inode_dirty(inode,
+						HFSPLUS_I_CAT_DIRTY);
+			} else {
+				err = -ERANGE;
+				goto end_setxattr;
+			}
+		} else if (be16_to_cpu(entry.type) == HFSPLUS_FILE) {
+			if (size == file_finderinfo_len) {
+				memcpy(&entry.file.user_info, value,
+						file_finderinfo_len);
+				hfs_bnode_write(cat_fd.bnode, &entry,
+					cat_fd.entryoffset,
+					sizeof(struct hfsplus_cat_file));
+				hfsplus_mark_inode_dirty(inode,
+						HFSPLUS_I_CAT_DIRTY);
+			} else {
+				err = -ERANGE;
+				goto end_setxattr;
+			}
+		} else {
+			err = -EOPNOTSUPP;
+			goto end_setxattr;
+		}
+		goto end_setxattr;
+	}
+
+	if (!HFSPLUS_SB(inode->i_sb)->attr_tree) {
+		err = hfsplus_create_attributes_file(inode->i_sb);
+		if (unlikely(err))
+			goto end_setxattr;
+	}
+
+	if (hfsplus_attr_exists(inode, name)) {
+		if (flags & XATTR_CREATE) {
+			pr_err("xattr exists yet\n");
+			err = -EOPNOTSUPP;
+			goto end_setxattr;
+		}
+		err = hfsplus_delete_attr(inode, name);
+		if (err)
+			goto end_setxattr;
+		err = hfsplus_create_attr(inode, name, value, size);
+		if (err)
+			goto end_setxattr;
+	} else {
+		if (flags & XATTR_REPLACE) {
+			pr_err("cannot replace xattr\n");
+			err = -EOPNOTSUPP;
+			goto end_setxattr;
+		}
+		err = hfsplus_create_attr(inode, name, value, size);
+		if (err)
+			goto end_setxattr;
+	}
+
+	cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
+	if (cat_entry_type == HFSPLUS_FOLDER) {
+		cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
+				    cat_fd.entryoffset +
+				    offsetof(struct hfsplus_cat_folder, flags));
+		cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
+		if (!strcmp_xattr_acl(name))
+			cat_entry_flags |= HFSPLUS_ACL_EXISTS;
+		hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+				offsetof(struct hfsplus_cat_folder, flags),
+				cat_entry_flags);
+		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+	} else if (cat_entry_type == HFSPLUS_FILE) {
+		cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
+				    cat_fd.entryoffset +
+				    offsetof(struct hfsplus_cat_file, flags));
+		cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
+		if (!strcmp_xattr_acl(name))
+			cat_entry_flags |= HFSPLUS_ACL_EXISTS;
+		hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+				    offsetof(struct hfsplus_cat_file, flags),
+				    cat_entry_flags);
+		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+	} else {
+		pr_err("invalid catalog entry type\n");
+		err = -EIO;
+		goto end_setxattr;
+	}
+
+end_setxattr:
+	hfs_find_exit(&cat_fd);
+	return err;
+}
+
+static int name_len(const char *xattr_name, int xattr_name_len)
+{
+	int len = xattr_name_len + 1;
+
+	if (!is_known_namespace(xattr_name))
+		len += XATTR_MAC_OSX_PREFIX_LEN;
+
+	return len;
+}
+
+static int copy_name(char *buffer, const char *xattr_name, int name_len)
+{
+	int len = name_len;
+	int offset = 0;
+
+	if (!is_known_namespace(xattr_name)) {
+		strncpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
+		offset += XATTR_MAC_OSX_PREFIX_LEN;
+		len += XATTR_MAC_OSX_PREFIX_LEN;
+	}
+
+	strncpy(buffer + offset, xattr_name, name_len);
+	memset(buffer + offset + name_len, 0, 1);
+	len += 1;
+
+	return len;
+}
+
+static ssize_t hfsplus_getxattr_finder_info(struct inode *inode,
+						void *value, size_t size)
+{
+	ssize_t res = 0;
+	struct hfs_find_data fd;
+	u16 entry_type;
+	u16 folder_rec_len = sizeof(struct DInfo) + sizeof(struct DXInfo);
+	u16 file_rec_len = sizeof(struct FInfo) + sizeof(struct FXInfo);
+	u16 record_len = max(folder_rec_len, file_rec_len);
+	u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
+	u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
+
+	if (size >= record_len) {
+		res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
+		if (res) {
+			pr_err("can't init xattr find struct\n");
+			return res;
+		}
+		res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
+		if (res)
+			goto end_getxattr_finder_info;
+		entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
+
+		if (entry_type == HFSPLUS_FOLDER) {
+			hfs_bnode_read(fd.bnode, folder_finder_info,
+				fd.entryoffset +
+				offsetof(struct hfsplus_cat_folder, user_info),
+				folder_rec_len);
+			memcpy(value, folder_finder_info, folder_rec_len);
+			res = folder_rec_len;
+		} else if (entry_type == HFSPLUS_FILE) {
+			hfs_bnode_read(fd.bnode, file_finder_info,
+				fd.entryoffset +
+				offsetof(struct hfsplus_cat_file, user_info),
+				file_rec_len);
+			memcpy(value, file_finder_info, file_rec_len);
+			res = file_rec_len;
+		} else {
+			res = -EOPNOTSUPP;
+			goto end_getxattr_finder_info;
+		}
+	} else
+		res = size ? -ERANGE : record_len;
+
+end_getxattr_finder_info:
+	if (size >= record_len)
+		hfs_find_exit(&fd);
+	return res;
+}
+
+ssize_t __hfsplus_getxattr(struct inode *inode, const char *name,
+			 void *value, size_t size)
+{
+	struct hfs_find_data fd;
+	hfsplus_attr_entry *entry;
+	__be32 xattr_record_type;
+	u32 record_type;
+	u16 record_length = 0;
+	ssize_t res = 0;
+
+	if ((!S_ISREG(inode->i_mode) &&
+			!S_ISDIR(inode->i_mode)) ||
+				HFSPLUS_IS_RSRC(inode))
+		return -EOPNOTSUPP;
+
+	if (!strcmp_xattr_finder_info(name))
+		return hfsplus_getxattr_finder_info(inode, value, size);
+
+	if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+		return -EOPNOTSUPP;
+
+	entry = hfsplus_alloc_attr_entry();
+	if (!entry) {
+		pr_err("can't allocate xattr entry\n");
+		return -ENOMEM;
+	}
+
+	res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
+	if (res) {
+		pr_err("can't init xattr find struct\n");
+		goto failed_getxattr_init;
+	}
+
+	res = hfsplus_find_attr(inode->i_sb, inode->i_ino, name, &fd);
+	if (res) {
+		if (res == -ENOENT)
+			res = -ENODATA;
+		else
+			pr_err("xattr searching failed\n");
+		goto out;
+	}
+
+	hfs_bnode_read(fd.bnode, &xattr_record_type,
+			fd.entryoffset, sizeof(xattr_record_type));
+	record_type = be32_to_cpu(xattr_record_type);
+	if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
+		record_length = hfs_bnode_read_u16(fd.bnode,
+				fd.entryoffset +
+				offsetof(struct hfsplus_attr_inline_data,
+				length));
+		if (record_length > HFSPLUS_MAX_INLINE_DATA_SIZE) {
+			pr_err("invalid xattr record size\n");
+			res = -EIO;
+			goto out;
+		}
+	} else if (record_type == HFSPLUS_ATTR_FORK_DATA ||
+			record_type == HFSPLUS_ATTR_EXTENTS) {
+		pr_err("only inline data xattr are supported\n");
+		res = -EOPNOTSUPP;
+		goto out;
+	} else {
+		pr_err("invalid xattr record\n");
+		res = -EIO;
+		goto out;
+	}
+
+	if (size) {
+		hfs_bnode_read(fd.bnode, entry, fd.entryoffset,
+				offsetof(struct hfsplus_attr_inline_data,
+					raw_bytes) + record_length);
+	}
+
+	if (size >= record_length) {
+		memcpy(value, entry->inline_data.raw_bytes, record_length);
+		res = record_length;
+	} else
+		res = size ? -ERANGE : record_length;
+
+out:
+	hfs_find_exit(&fd);
+
+failed_getxattr_init:
+	hfsplus_destroy_attr_entry(entry);
+	return res;
+}
+
+static inline int can_list(const char *xattr_name)
+{
+	if (!xattr_name)
+		return 0;
+
+	return strncmp(xattr_name, XATTR_TRUSTED_PREFIX,
+			XATTR_TRUSTED_PREFIX_LEN) ||
+				capable(CAP_SYS_ADMIN);
+}
+
+static ssize_t hfsplus_listxattr_finder_info(struct dentry *dentry,
+						char *buffer, size_t size)
+{
+	ssize_t res = 0;
+	struct inode *inode = dentry->d_inode;
+	struct hfs_find_data fd;
+	u16 entry_type;
+	u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
+	u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
+	unsigned long len, found_bit;
+	int xattr_name_len, symbols_count;
+
+	res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
+	if (res) {
+		pr_err("can't init xattr find struct\n");
+		return res;
+	}
+
+	res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
+	if (res)
+		goto end_listxattr_finder_info;
+
+	entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
+	if (entry_type == HFSPLUS_FOLDER) {
+		len = sizeof(struct DInfo) + sizeof(struct DXInfo);
+		hfs_bnode_read(fd.bnode, folder_finder_info,
+				fd.entryoffset +
+				offsetof(struct hfsplus_cat_folder, user_info),
+				len);
+		found_bit = find_first_bit((void *)folder_finder_info, len*8);
+	} else if (entry_type == HFSPLUS_FILE) {
+		len = sizeof(struct FInfo) + sizeof(struct FXInfo);
+		hfs_bnode_read(fd.bnode, file_finder_info,
+				fd.entryoffset +
+				offsetof(struct hfsplus_cat_file, user_info),
+				len);
+		found_bit = find_first_bit((void *)file_finder_info, len*8);
+	} else {
+		res = -EOPNOTSUPP;
+		goto end_listxattr_finder_info;
+	}
+
+	if (found_bit >= (len*8))
+		res = 0;
+	else {
+		symbols_count = sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME) - 1;
+		xattr_name_len =
+			name_len(HFSPLUS_XATTR_FINDER_INFO_NAME, symbols_count);
+		if (!buffer || !size) {
+			if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME))
+				res = xattr_name_len;
+		} else if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME)) {
+			if (size < xattr_name_len)
+				res = -ERANGE;
+			else {
+				res = copy_name(buffer,
+						HFSPLUS_XATTR_FINDER_INFO_NAME,
+						symbols_count);
+			}
+		}
+	}
+
+end_listxattr_finder_info:
+	hfs_find_exit(&fd);
+
+	return res;
+}
+
+ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+	ssize_t err;
+	ssize_t res = 0;
+	struct inode *inode = dentry->d_inode;
+	struct hfs_find_data fd;
+	u16 key_len = 0;
+	struct hfsplus_attr_key attr_key;
+	char *strbuf;
+	int xattr_name_len;
+
+	if ((!S_ISREG(inode->i_mode) &&
+			!S_ISDIR(inode->i_mode)) ||
+				HFSPLUS_IS_RSRC(inode))
+		return -EOPNOTSUPP;
+
+	res = hfsplus_listxattr_finder_info(dentry, buffer, size);
+	if (res < 0)
+		return res;
+	else if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+		return (res == 0) ? -EOPNOTSUPP : res;
+
+	err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
+	if (err) {
+		pr_err("can't init xattr find struct\n");
+		return err;
+	}
+
+	strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN +
+			XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
+	if (!strbuf) {
+		res = -ENOMEM;
+		goto out;
+	}
+
+	err = hfsplus_find_attr(inode->i_sb, inode->i_ino, NULL, &fd);
+	if (err) {
+		if (err == -ENOENT) {
+			if (res == 0)
+				res = -ENODATA;
+			goto end_listxattr;
+		} else {
+			res = err;
+			goto end_listxattr;
+		}
+	}
+
+	for (;;) {
+		key_len = hfs_bnode_read_u16(fd.bnode, fd.keyoffset);
+		if (key_len == 0 || key_len > fd.tree->max_key_len) {
+			pr_err("invalid xattr key length: %d\n", key_len);
+			res = -EIO;
+			goto end_listxattr;
+		}
+
+		hfs_bnode_read(fd.bnode, &attr_key,
+				fd.keyoffset, key_len + sizeof(key_len));
+
+		if (be32_to_cpu(attr_key.cnid) != inode->i_ino)
+			goto end_listxattr;
+
+		xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
+		if (hfsplus_uni2asc(inode->i_sb,
+			(const struct hfsplus_unistr *)&fd.key->attr.key_name,
+					strbuf, &xattr_name_len)) {
+			pr_err("unicode conversion failed\n");
+			res = -EIO;
+			goto end_listxattr;
+		}
+
+		if (!buffer || !size) {
+			if (can_list(strbuf))
+				res += name_len(strbuf, xattr_name_len);
+		} else if (can_list(strbuf)) {
+			if (size < (res + name_len(strbuf, xattr_name_len))) {
+				res = -ERANGE;
+				goto end_listxattr;
+			} else
+				res += copy_name(buffer + res,
+						strbuf, xattr_name_len);
+		}
+
+		if (hfs_brec_goto(&fd, 1))
+			goto end_listxattr;
+	}
+
+end_listxattr:
+	kfree(strbuf);
+out:
+	hfs_find_exit(&fd);
+	return res;
+}
+
+static int hfsplus_removexattr(struct inode *inode, const char *name)
+{
+	int err = 0;
+	struct hfs_find_data cat_fd;
+	u16 flags;
+	u16 cat_entry_type;
+	int is_xattr_acl_deleted = 0;
+	int is_all_xattrs_deleted = 0;
+
+	if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
+		return -EOPNOTSUPP;
+
+	if (!strcmp_xattr_finder_info(name))
+		return -EOPNOTSUPP;
+
+	err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
+	if (err) {
+		pr_err("can't init xattr find struct\n");
+		return err;
+	}
+
+	err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
+	if (err) {
+		pr_err("catalog searching failed\n");
+		goto end_removexattr;
+	}
+
+	err = hfsplus_delete_attr(inode, name);
+	if (err)
+		goto end_removexattr;
+
+	is_xattr_acl_deleted = !strcmp_xattr_acl(name);
+	is_all_xattrs_deleted = !hfsplus_attr_exists(inode, NULL);
+
+	if (!is_xattr_acl_deleted && !is_all_xattrs_deleted)
+		goto end_removexattr;
+
+	cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
+
+	if (cat_entry_type == HFSPLUS_FOLDER) {
+		flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
+				offsetof(struct hfsplus_cat_folder, flags));
+		if (is_xattr_acl_deleted)
+			flags &= ~HFSPLUS_ACL_EXISTS;
+		if (is_all_xattrs_deleted)
+			flags &= ~HFSPLUS_XATTR_EXISTS;
+		hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+				offsetof(struct hfsplus_cat_folder, flags),
+				flags);
+		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+	} else if (cat_entry_type == HFSPLUS_FILE) {
+		flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
+				offsetof(struct hfsplus_cat_file, flags));
+		if (is_xattr_acl_deleted)
+			flags &= ~HFSPLUS_ACL_EXISTS;
+		if (is_all_xattrs_deleted)
+			flags &= ~HFSPLUS_XATTR_EXISTS;
+		hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
+				offsetof(struct hfsplus_cat_file, flags),
+				flags);
+		hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
+	} else {
+		pr_err("invalid catalog entry type\n");
+		err = -EIO;
+		goto end_removexattr;
+	}
+
+end_removexattr:
+	hfs_find_exit(&cat_fd);
+	return err;
+}
+
+static int hfsplus_osx_getxattr(struct dentry *dentry, const char *name,
+					void *buffer, size_t size, int type)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	/*
+	 * Don't allow retrieving properly prefixed attributes
+	 * by prepending them with "osx."
+	 */
+	if (is_known_namespace(name))
+		return -EOPNOTSUPP;
+
+	/*
+	 * osx is the namespace we use to indicate an unprefixed
+	 * attribute on the filesystem (like the ones that OS X
+	 * creates), so we pass the name through unmodified (after
+	 * ensuring it doesn't conflict with another namespace).
+	 */
+	return hfsplus_getxattr(dentry, name, buffer, size);
+}
+
+static int hfsplus_osx_setxattr(struct dentry *dentry, const char *name,
+		const void *buffer, size_t size, int flags, int type)
+{
+	if (!strcmp(name, ""))
+		return -EINVAL;
+
+	/*
+	 * Don't allow setting properly prefixed attributes
+	 * by prepending them with "osx."
+	 */
+	if (is_known_namespace(name))
+		return -EOPNOTSUPP;
+
+	/*
+	 * osx is the namespace we use to indicate an unprefixed
+	 * attribute on the filesystem (like the ones that OS X
+	 * creates), so we pass the name through unmodified (after
+	 * ensuring it doesn't conflict with another namespace).
+	 */
+	return hfsplus_setxattr(dentry, name, buffer, size, flags);
+}
+
+static size_t hfsplus_osx_listxattr(struct dentry *dentry, char *list,
+		size_t list_size, const char *name, size_t name_len, int type)
+{
+	/*
+	 * This method is not used.
+	 * It is used hfsplus_listxattr() instead of generic_listxattr().
+	 */
+	return -EOPNOTSUPP;
+}
+
+const struct xattr_handler hfsplus_xattr_osx_handler = {
+	.prefix	= XATTR_MAC_OSX_PREFIX,
+	.list	= hfsplus_osx_listxattr,
+	.get	= hfsplus_osx_getxattr,
+	.set	= hfsplus_osx_setxattr,
+};