fs/hfsplus/xattr.c

   1 /*
   2  * linux/fs/hfsplus/xattr.c
   3  *
   4  * Vyacheslav Dubeyko <slava@dubeyko.com>
   5  *
   6  * Logic of processing extended attributes
   7  */
   8
   9 #include "hfsplus_fs.h"
  10 #include <linux/posix_acl_xattr.h>
  11 #include <linux/nls.h>
  12 #include "xattr.h"
  13 #include "acl.h"
  14
  15 static int hfsplus_removexattr(struct inode *inode, const char *name);
  16
  17 const struct xattr_handler *hfsplus_xattr_handlers[] = {
  18         &hfsplus_xattr_osx_handler,
  19         &hfsplus_xattr_user_handler,
  20         &hfsplus_xattr_trusted_handler,
  21 #ifdef CONFIG_HFSPLUS_FS_POSIX_ACL
  22         &posix_acl_access_xattr_handler,
  23         &posix_acl_default_xattr_handler,
  24 #endif
  25         &hfsplus_xattr_security_handler,
  26         NULL
  27 };
  28
  29 static int strcmp_xattr_finder_info(const char *name)
  30 {
  31         if (name) {
  32                 return strncmp(name, HFSPLUS_XATTR_FINDER_INFO_NAME,
  33                                 sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME));
  34         }
  35         return -1;
  36 }
  37
  38 static int strcmp_xattr_acl(const char *name)
  39 {
  40         if (name) {
  41                 return strncmp(name, HFSPLUS_XATTR_ACL_NAME,
  42                                 sizeof(HFSPLUS_XATTR_ACL_NAME));
  43         }
  44         return -1;
  45 }
  46
  47 static inline int is_known_namespace(const char *name)
  48 {
  49         if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) &&
  50             strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) &&
  51             strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
  52             strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN))
  53                 return false;
  54
  55         return true;
  56 }
  57
  58 static void hfsplus_init_header_node(struct inode *attr_file,
  59                                         u32 clump_size,
  60                                         char *buf, u16 node_size)
  61 {
  62         struct hfs_bnode_desc *desc;
  63         struct hfs_btree_header_rec *head;
  64         u16 offset;
  65         __be16 *rec_offsets;
  66         u32 hdr_node_map_rec_bits;
  67         char *bmp;
  68         u32 used_nodes;
  69         u32 used_bmp_bytes;
  70         u64 tmp;
  71
  72         hfs_dbg(ATTR_MOD, "init_hdr_attr_file: clump %u, node_size %u\n",
  73                 clump_size, node_size);
  74
  75         /* The end of the node contains list of record offsets */
  76         rec_offsets = (__be16 *)(buf + node_size);
  77
  78         desc = (struct hfs_bnode_desc *)buf;
  79         desc->type = HFS_NODE_HEADER;
  80         desc->num_recs = cpu_to_be16(HFSPLUS_BTREE_HDR_NODE_RECS_COUNT);
  81         offset = sizeof(struct hfs_bnode_desc);
  82         *--rec_offsets = cpu_to_be16(offset);
  83
  84         head = (struct hfs_btree_header_rec *)(buf + offset);
  85         head->node_size = cpu_to_be16(node_size);
  86         tmp = i_size_read(attr_file);
  87         do_div(tmp, node_size);
  88         head->node_count = cpu_to_be32(tmp);
  89         head->free_nodes = cpu_to_be32(be32_to_cpu(head->node_count) - 1);
  90         head->clump_size = cpu_to_be32(clump_size);
  91         head->attributes |= cpu_to_be32(HFS_TREE_BIGKEYS | HFS_TREE_VARIDXKEYS);
  92         head->max_key_len = cpu_to_be16(HFSPLUS_ATTR_KEYLEN - sizeof(u16));
  93         offset += sizeof(struct hfs_btree_header_rec);
  94         *--rec_offsets = cpu_to_be16(offset);
  95         offset += HFSPLUS_BTREE_HDR_USER_BYTES;
  96         *--rec_offsets = cpu_to_be16(offset);
  97
  98         hdr_node_map_rec_bits = 8 * (node_size - offset - (4 * sizeof(u16)));
  99         if (be32_to_cpu(head->node_count) > hdr_node_map_rec_bits) {
 100                 u32 map_node_bits;
 101                 u32 map_nodes;
 102
 103                 desc->next = cpu_to_be32(be32_to_cpu(head->leaf_tail) + 1);
 104                 map_node_bits = 8 * (node_size - sizeof(struct hfs_bnode_desc) -
 105                                         (2 * sizeof(u16)) - 2);
 106                 map_nodes = (be32_to_cpu(head->node_count) -
 107                                 hdr_node_map_rec_bits +
 108                                 (map_node_bits - 1)) / map_node_bits;
 109                 be32_add_cpu(&head->free_nodes, 0 - map_nodes);
 110         }
 111
 112         bmp = buf + offset;
 113         used_nodes =
 114                 be32_to_cpu(head->node_count) - be32_to_cpu(head->free_nodes);
 115         used_bmp_bytes = used_nodes / 8;
 116         if (used_bmp_bytes) {
 117                 memset(bmp, 0xFF, used_bmp_bytes);
 118                 bmp += used_bmp_bytes;
 119                 used_nodes %= 8;
 120         }
 121         *bmp = ~(0xFF >> used_nodes);
 122         offset += hdr_node_map_rec_bits / 8;
 123         *--rec_offsets = cpu_to_be16(offset);
 124 }
 125
 126 static int hfsplus_create_attributes_file(struct super_block *sb)
 127 {
 128         int err = 0;
 129         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 130         struct inode *attr_file;
 131         struct hfsplus_inode_info *hip;
 132         u32 clump_size;
 133         u16 node_size = HFSPLUS_ATTR_TREE_NODE_SIZE;
 134         char *buf;
 135         int index, written;
 136         struct address_space *mapping;
 137         struct page *page;
 138         int old_state = HFSPLUS_EMPTY_ATTR_TREE;
 139
 140         hfs_dbg(ATTR_MOD, "create_attr_file: ino %d\n", HFSPLUS_ATTR_CNID);
 141
 142 check_attr_tree_state_again:
 143         switch (atomic_read(&sbi->attr_tree_state)) {
 144         case HFSPLUS_EMPTY_ATTR_TREE:
 145                 if (old_state != atomic_cmpxchg(&sbi->attr_tree_state,
 146                                                 old_state,
 147                                                 HFSPLUS_CREATING_ATTR_TREE))
 148                         goto check_attr_tree_state_again;
 149                 break;
 150         case HFSPLUS_CREATING_ATTR_TREE:
 151                 /*
 152                  * This state means that another thread is in process
 153                  * of AttributesFile creation. Theoretically, it is
 154                  * possible to be here. But really __setxattr() method
 155                  * first of all calls hfs_find_init() for lookup in
 156                  * B-tree of CatalogFile. This method locks mutex of
 157                  * CatalogFile's B-tree. As a result, if some thread
 158                  * is inside AttributedFile creation operation then
 159                  * another threads will be waiting unlocking of
 160                  * CatalogFile's B-tree's mutex. However, if code will
 161                  * change then we will return error code (-EAGAIN) from
 162                  * here. Really, it means that first try to set of xattr
 163                  * fails with error but second attempt will have success.
 164                  */
 165                 return -EAGAIN;
 166         case HFSPLUS_VALID_ATTR_TREE:
 167                 return 0;
 168         case HFSPLUS_FAILED_ATTR_TREE:
 169                 return -EOPNOTSUPP;
 170         default:
 171                 BUG();
 172         }
 173
 174         attr_file = hfsplus_iget(sb, HFSPLUS_ATTR_CNID);
 175         if (IS_ERR(attr_file)) {
 176                 pr_err("failed to load attributes file\n");
 177                 return PTR_ERR(attr_file);
 178         }
 179
 180         BUG_ON(i_size_read(attr_file) != 0);
 181
 182         hip = HFSPLUS_I(attr_file);
 183
 184         clump_size = hfsplus_calc_btree_clump_size(sb->s_blocksize,
 185                                                     node_size,
 186                                                     sbi->sect_count,
 187                                                     HFSPLUS_ATTR_CNID);
 188
 189         mutex_lock(&hip->extents_lock);
 190         hip->clump_blocks = clump_size >> sbi->alloc_blksz_shift;
 191         mutex_unlock(&hip->extents_lock);
 192
 193         if (sbi->free_blocks <= (hip->clump_blocks << 1)) {
 194                 err = -ENOSPC;
 195                 goto end_attr_file_creation;
 196         }
 197
 198         while (hip->alloc_blocks < hip->clump_blocks) {
 199                 err = hfsplus_file_extend(attr_file, false);
 200                 if (unlikely(err)) {
 201                         pr_err("failed to extend attributes file\n");
 202                         goto end_attr_file_creation;
 203                 }
 204                 hip->phys_size = attr_file->i_size =
 205                         (loff_t)hip->alloc_blocks << sbi->alloc_blksz_shift;
 206                 hip->fs_blocks = hip->alloc_blocks << sbi->fs_shift;
 207                 inode_set_bytes(attr_file, attr_file->i_size);
 208         }
 209
 210         buf = kzalloc(node_size, GFP_NOFS);
 211         if (!buf) {
 212                 pr_err("failed to allocate memory for header node\n");
 213                 err = -ENOMEM;
 214                 goto end_attr_file_creation;
 215         }
 216
 217         hfsplus_init_header_node(attr_file, clump_size, buf, node_size);
 218
 219         mapping = attr_file->i_mapping;
 220
 221         index = 0;
 222         written = 0;
 223         for (; written < node_size; index++, written += PAGE_CACHE_SIZE) {
 224                 void *kaddr;
 225
 226                 page = read_mapping_page(mapping, index, NULL);
 227                 if (IS_ERR(page)) {
 228                         err = PTR_ERR(page);
 229                         goto failed_header_node_init;
 230                 }
 231
 232                 kaddr = kmap_atomic(page);
 233                 memcpy(kaddr, buf + written,
 234                         min_t(size_t, PAGE_CACHE_SIZE, node_size - written));
 235                 kunmap_atomic(kaddr);
 236
 237                 set_page_dirty(page);
 238                 page_cache_release(page);
 239         }
 240
 241         hfsplus_mark_inode_dirty(attr_file, HFSPLUS_I_ATTR_DIRTY);
 242
 243         sbi->attr_tree = hfs_btree_open(sb, HFSPLUS_ATTR_CNID);
 244         if (!sbi->attr_tree)
 245                 pr_err("failed to load attributes file\n");
 246
 247 failed_header_node_init:
 248         kfree(buf);
 249
 250 end_attr_file_creation:
 251         iput(attr_file);
 252
 253         if (!err)
 254                 atomic_set(&sbi->attr_tree_state, HFSPLUS_VALID_ATTR_TREE);
 255         else if (err == -ENOSPC)
 256                 atomic_set(&sbi->attr_tree_state, HFSPLUS_EMPTY_ATTR_TREE);
 257         else
 258                 atomic_set(&sbi->attr_tree_state, HFSPLUS_FAILED_ATTR_TREE);
 259
 260         return err;
 261 }
 262
 263 int __hfsplus_setxattr(struct inode *inode, const char *name,
 264                         const void *value, size_t size, int flags)
 265 {
 266         int err = 0;
 267         struct hfs_find_data cat_fd;
 268         hfsplus_cat_entry entry;
 269         u16 cat_entry_flags, cat_entry_type;
 270         u16 folder_finderinfo_len = sizeof(struct DInfo) +
 271                                         sizeof(struct DXInfo);
 272         u16 file_finderinfo_len = sizeof(struct FInfo) +
 273                                         sizeof(struct FXInfo);
 274
 275         if ((!S_ISREG(inode->i_mode) &&
 276                         !S_ISDIR(inode->i_mode)) ||
 277                                 HFSPLUS_IS_RSRC(inode))
 278                 return -EOPNOTSUPP;
 279
 280         if (value == NULL)
 281                 return hfsplus_removexattr(inode, name);
 282
 283         err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
 284         if (err) {
 285                 pr_err("can't init xattr find struct\n");
 286                 return err;
 287         }
 288
 289         err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
 290         if (err) {
 291                 pr_err("catalog searching failed\n");
 292                 goto end_setxattr;
 293         }
 294
 295         if (!strcmp_xattr_finder_info(name)) {
 296                 if (flags & XATTR_CREATE) {
 297                         pr_err("xattr exists yet\n");
 298                         err = -EOPNOTSUPP;
 299                         goto end_setxattr;
 300                 }
 301                 hfs_bnode_read(cat_fd.bnode, &entry, cat_fd.entryoffset,
 302                                         sizeof(hfsplus_cat_entry));
 303                 if (be16_to_cpu(entry.type) == HFSPLUS_FOLDER) {
 304                         if (size == folder_finderinfo_len) {
 305                                 memcpy(&entry.folder.user_info, value,
 306                                                 folder_finderinfo_len);
 307                                 hfs_bnode_write(cat_fd.bnode, &entry,
 308                                         cat_fd.entryoffset,
 309                                         sizeof(struct hfsplus_cat_folder));
 310                                 hfsplus_mark_inode_dirty(inode,
 311                                                 HFSPLUS_I_CAT_DIRTY);
 312                         } else {
 313                                 err = -ERANGE;
 314                                 goto end_setxattr;
 315                         }
 316                 } else if (be16_to_cpu(entry.type) == HFSPLUS_FILE) {
 317                         if (size == file_finderinfo_len) {
 318                                 memcpy(&entry.file.user_info, value,
 319                                                 file_finderinfo_len);
 320                                 hfs_bnode_write(cat_fd.bnode, &entry,
 321                                         cat_fd.entryoffset,
 322                                         sizeof(struct hfsplus_cat_file));
 323                                 hfsplus_mark_inode_dirty(inode,
 324                                                 HFSPLUS_I_CAT_DIRTY);
 325                         } else {
 326                                 err = -ERANGE;
 327                                 goto end_setxattr;
 328                         }
 329                 } else {
 330                         err = -EOPNOTSUPP;
 331                         goto end_setxattr;
 332                 }
 333                 goto end_setxattr;
 334         }
 335
 336         if (!HFSPLUS_SB(inode->i_sb)->attr_tree) {
 337                 err = hfsplus_create_attributes_file(inode->i_sb);
 338                 if (unlikely(err))
 339                         goto end_setxattr;
 340         }
 341
 342         if (hfsplus_attr_exists(inode, name)) {
 343                 if (flags & XATTR_CREATE) {
 344                         pr_err("xattr exists yet\n");
 345                         err = -EOPNOTSUPP;
 346                         goto end_setxattr;
 347                 }
 348                 err = hfsplus_delete_attr(inode, name);
 349                 if (err)
 350                         goto end_setxattr;
 351                 err = hfsplus_create_attr(inode, name, value, size);
 352                 if (err)
 353                         goto end_setxattr;
 354         } else {
 355                 if (flags & XATTR_REPLACE) {
 356                         pr_err("cannot replace xattr\n");
 357                         err = -EOPNOTSUPP;
 358                         goto end_setxattr;
 359                 }
 360                 err = hfsplus_create_attr(inode, name, value, size);
 361                 if (err)
 362                         goto end_setxattr;
 363         }
 364
 365         cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
 366         if (cat_entry_type == HFSPLUS_FOLDER) {
 367                 cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
 368                                     cat_fd.entryoffset +
 369                                     offsetof(struct hfsplus_cat_folder, flags));
 370                 cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
 371                 if (!strcmp_xattr_acl(name))
 372                         cat_entry_flags |= HFSPLUS_ACL_EXISTS;
 373                 hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 374                                 offsetof(struct hfsplus_cat_folder, flags),
 375                                 cat_entry_flags);
 376                 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 377         } else if (cat_entry_type == HFSPLUS_FILE) {
 378                 cat_entry_flags = hfs_bnode_read_u16(cat_fd.bnode,
 379                                     cat_fd.entryoffset +
 380                                     offsetof(struct hfsplus_cat_file, flags));
 381                 cat_entry_flags |= HFSPLUS_XATTR_EXISTS;
 382                 if (!strcmp_xattr_acl(name))
 383                         cat_entry_flags |= HFSPLUS_ACL_EXISTS;
 384                 hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 385                                     offsetof(struct hfsplus_cat_file, flags),
 386                                     cat_entry_flags);
 387                 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 388         } else {
 389                 pr_err("invalid catalog entry type\n");
 390                 err = -EIO;
 391                 goto end_setxattr;
 392         }
 393
 394 end_setxattr:
 395         hfs_find_exit(&cat_fd);
 396         return err;
 397 }
 398
 399 static int name_len(const char *xattr_name, int xattr_name_len)
 400 {
 401         int len = xattr_name_len + 1;
 402
 403         if (!is_known_namespace(xattr_name))
 404                 len += XATTR_MAC_OSX_PREFIX_LEN;
 405
 406         return len;
 407 }
 408
 409 static int copy_name(char *buffer, const char *xattr_name, int name_len)
 410 {
 411         int len = name_len;
 412         int offset = 0;
 413
 414         if (!is_known_namespace(xattr_name)) {
 415                 strncpy(buffer, XATTR_MAC_OSX_PREFIX, XATTR_MAC_OSX_PREFIX_LEN);
 416                 offset += XATTR_MAC_OSX_PREFIX_LEN;
 417                 len += XATTR_MAC_OSX_PREFIX_LEN;
 418         }
 419
 420         strncpy(buffer + offset, xattr_name, name_len);
 421         memset(buffer + offset + name_len, 0, 1);
 422         len += 1;
 423
 424         return len;
 425 }
 426
 427 static ssize_t hfsplus_getxattr_finder_info(struct inode *inode,
 428                                                 void *value, size_t size)
 429 {
 430         ssize_t res = 0;
 431         struct hfs_find_data fd;
 432         u16 entry_type;
 433         u16 folder_rec_len = sizeof(struct DInfo) + sizeof(struct DXInfo);
 434         u16 file_rec_len = sizeof(struct FInfo) + sizeof(struct FXInfo);
 435         u16 record_len = max(folder_rec_len, file_rec_len);
 436         u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
 437         u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
 438
 439         if (size >= record_len) {
 440                 res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 441                 if (res) {
 442                         pr_err("can't init xattr find struct\n");
 443                         return res;
 444                 }
 445                 res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 446                 if (res)
 447                         goto end_getxattr_finder_info;
 448                 entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
 449
 450                 if (entry_type == HFSPLUS_FOLDER) {
 451                         hfs_bnode_read(fd.bnode, folder_finder_info,
 452                                 fd.entryoffset +
 453                                 offsetof(struct hfsplus_cat_folder, user_info),
 454                                 folder_rec_len);
 455                         memcpy(value, folder_finder_info, folder_rec_len);
 456                         res = folder_rec_len;
 457                 } else if (entry_type == HFSPLUS_FILE) {
 458                         hfs_bnode_read(fd.bnode, file_finder_info,
 459                                 fd.entryoffset +
 460                                 offsetof(struct hfsplus_cat_file, user_info),
 461                                 file_rec_len);
 462                         memcpy(value, file_finder_info, file_rec_len);
 463                         res = file_rec_len;
 464                 } else {
 465                         res = -EOPNOTSUPP;
 466                         goto end_getxattr_finder_info;
 467                 }
 468         } else
 469                 res = size ? -ERANGE : record_len;
 470
 471 end_getxattr_finder_info:
 472         if (size >= record_len)
 473                 hfs_find_exit(&fd);
 474         return res;
 475 }
 476
 477 ssize_t __hfsplus_getxattr(struct inode *inode, const char *name,
 478                          void *value, size_t size)
 479 {
 480         struct hfs_find_data fd;
 481         hfsplus_attr_entry *entry;
 482         __be32 xattr_record_type;
 483         u32 record_type;
 484         u16 record_length = 0;
 485         ssize_t res = 0;
 486
 487         if ((!S_ISREG(inode->i_mode) &&
 488                         !S_ISDIR(inode->i_mode)) ||
 489                                 HFSPLUS_IS_RSRC(inode))
 490                 return -EOPNOTSUPP;
 491
 492         if (!strcmp_xattr_finder_info(name))
 493                 return hfsplus_getxattr_finder_info(inode, value, size);
 494
 495         if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 496                 return -EOPNOTSUPP;
 497
 498         entry = hfsplus_alloc_attr_entry();
 499         if (!entry) {
 500                 pr_err("can't allocate xattr entry\n");
 501                 return -ENOMEM;
 502         }
 503
 504         res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
 505         if (res) {
 506                 pr_err("can't init xattr find struct\n");
 507                 goto failed_getxattr_init;
 508         }
 509
 510         res = hfsplus_find_attr(inode->i_sb, inode->i_ino, name, &fd);
 511         if (res) {
 512                 if (res == -ENOENT)
 513                         res = -ENODATA;
 514                 else
 515                         pr_err("xattr searching failed\n");
 516                 goto out;
 517         }
 518
 519         hfs_bnode_read(fd.bnode, &xattr_record_type,
 520                         fd.entryoffset, sizeof(xattr_record_type));
 521         record_type = be32_to_cpu(xattr_record_type);
 522         if (record_type == HFSPLUS_ATTR_INLINE_DATA) {
 523                 record_length = hfs_bnode_read_u16(fd.bnode,
 524                                 fd.entryoffset +
 525                                 offsetof(struct hfsplus_attr_inline_data,
 526                                 length));
 527                 if (record_length > HFSPLUS_MAX_INLINE_DATA_SIZE) {
 528                         pr_err("invalid xattr record size\n");
 529                         res = -EIO;
 530                         goto out;
 531                 }
 532         } else if (record_type == HFSPLUS_ATTR_FORK_DATA ||
 533                         record_type == HFSPLUS_ATTR_EXTENTS) {
 534                 pr_err("only inline data xattr are supported\n");
 535                 res = -EOPNOTSUPP;
 536                 goto out;
 537         } else {
 538                 pr_err("invalid xattr record\n");
 539                 res = -EIO;
 540                 goto out;
 541         }
 542
 543         if (size) {
 544                 hfs_bnode_read(fd.bnode, entry, fd.entryoffset,
 545                                 offsetof(struct hfsplus_attr_inline_data,
 546                                         raw_bytes) + record_length);
 547         }
 548
 549         if (size >= record_length) {
 550                 memcpy(value, entry->inline_data.raw_bytes, record_length);
 551                 res = record_length;
 552         } else
 553                 res = size ? -ERANGE : record_length;
 554
 555 out:
 556         hfs_find_exit(&fd);
 557
 558 failed_getxattr_init:
 559         hfsplus_destroy_attr_entry(entry);
 560         return res;
 561 }
 562
 563 static inline int can_list(const char *xattr_name)
 564 {
 565         if (!xattr_name)
 566                 return 0;
 567
 568         return strncmp(xattr_name, XATTR_TRUSTED_PREFIX,
 569                         XATTR_TRUSTED_PREFIX_LEN) ||
 570                                 capable(CAP_SYS_ADMIN);
 571 }
 572
 573 static ssize_t hfsplus_listxattr_finder_info(struct dentry *dentry,
 574                                                 char *buffer, size_t size)
 575 {
 576         ssize_t res = 0;
 577         struct inode *inode = dentry->d_inode;
 578         struct hfs_find_data fd;
 579         u16 entry_type;
 580         u8 folder_finder_info[sizeof(struct DInfo) + sizeof(struct DXInfo)];
 581         u8 file_finder_info[sizeof(struct FInfo) + sizeof(struct FXInfo)];
 582         unsigned long len, found_bit;
 583         int xattr_name_len, symbols_count;
 584
 585         res = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
 586         if (res) {
 587                 pr_err("can't init xattr find struct\n");
 588                 return res;
 589         }
 590
 591         res = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
 592         if (res)
 593                 goto end_listxattr_finder_info;
 594
 595         entry_type = hfs_bnode_read_u16(fd.bnode, fd.entryoffset);
 596         if (entry_type == HFSPLUS_FOLDER) {
 597                 len = sizeof(struct DInfo) + sizeof(struct DXInfo);
 598                 hfs_bnode_read(fd.bnode, folder_finder_info,
 599                                 fd.entryoffset +
 600                                 offsetof(struct hfsplus_cat_folder, user_info),
 601                                 len);
 602                 found_bit = find_first_bit((void *)folder_finder_info, len*8);
 603         } else if (entry_type == HFSPLUS_FILE) {
 604                 len = sizeof(struct FInfo) + sizeof(struct FXInfo);
 605                 hfs_bnode_read(fd.bnode, file_finder_info,
 606                                 fd.entryoffset +
 607                                 offsetof(struct hfsplus_cat_file, user_info),
 608                                 len);
 609                 found_bit = find_first_bit((void *)file_finder_info, len*8);
 610         } else {
 611                 res = -EOPNOTSUPP;
 612                 goto end_listxattr_finder_info;
 613         }
 614
 615         if (found_bit >= (len*8))
 616                 res = 0;
 617         else {
 618                 symbols_count = sizeof(HFSPLUS_XATTR_FINDER_INFO_NAME) - 1;
 619                 xattr_name_len =
 620                         name_len(HFSPLUS_XATTR_FINDER_INFO_NAME, symbols_count);
 621                 if (!buffer || !size) {
 622                         if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME))
 623                                 res = xattr_name_len;
 624                 } else if (can_list(HFSPLUS_XATTR_FINDER_INFO_NAME)) {
 625                         if (size < xattr_name_len)
 626                                 res = -ERANGE;
 627                         else {
 628                                 res = copy_name(buffer,
 629                                                 HFSPLUS_XATTR_FINDER_INFO_NAME,
 630                                                 symbols_count);
 631                         }
 632                 }
 633         }
 634
 635 end_listxattr_finder_info:
 636         hfs_find_exit(&fd);
 637
 638         return res;
 639 }
 640
 641 ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
 642 {
 643         ssize_t err;
 644         ssize_t res = 0;
 645         struct inode *inode = dentry->d_inode;
 646         struct hfs_find_data fd;
 647         u16 key_len = 0;
 648         struct hfsplus_attr_key attr_key;
 649         char *strbuf;
 650         int xattr_name_len;
 651
 652         if ((!S_ISREG(inode->i_mode) &&
 653                         !S_ISDIR(inode->i_mode)) ||
 654                                 HFSPLUS_IS_RSRC(inode))
 655                 return -EOPNOTSUPP;
 656
 657         res = hfsplus_listxattr_finder_info(dentry, buffer, size);
 658         if (res < 0)
 659                 return res;
 660         else if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 661                 return (res == 0) ? -EOPNOTSUPP : res;
 662
 663         err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->attr_tree, &fd);
 664         if (err) {
 665                 pr_err("can't init xattr find struct\n");
 666                 return err;
 667         }
 668
 669         strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN +
 670                         XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
 671         if (!strbuf) {
 672                 res = -ENOMEM;
 673                 goto out;
 674         }
 675
 676         err = hfsplus_find_attr(inode->i_sb, inode->i_ino, NULL, &fd);
 677         if (err) {
 678                 if (err == -ENOENT) {
 679                         if (res == 0)
 680                                 res = -ENODATA;
 681                         goto end_listxattr;
 682                 } else {
 683                         res = err;
 684                         goto end_listxattr;
 685                 }
 686         }
 687
 688         for (;;) {
 689                 key_len = hfs_bnode_read_u16(fd.bnode, fd.keyoffset);
 690                 if (key_len == 0 || key_len > fd.tree->max_key_len) {
 691                         pr_err("invalid xattr key length: %d\n", key_len);
 692                         res = -EIO;
 693                         goto end_listxattr;
 694                 }
 695
 696                 hfs_bnode_read(fd.bnode, &attr_key,
 697                                 fd.keyoffset, key_len + sizeof(key_len));
 698
 699                 if (be32_to_cpu(attr_key.cnid) != inode->i_ino)
 700                         goto end_listxattr;
 701
 702                 xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
 703                 if (hfsplus_uni2asc(inode->i_sb,
 704                         (const struct hfsplus_unistr *)&fd.key->attr.key_name,
 705                                         strbuf, &xattr_name_len)) {
 706                         pr_err("unicode conversion failed\n");
 707                         res = -EIO;
 708                         goto end_listxattr;
 709                 }
 710
 711                 if (!buffer || !size) {
 712                         if (can_list(strbuf))
 713                                 res += name_len(strbuf, xattr_name_len);
 714                 } else if (can_list(strbuf)) {
 715                         if (size < (res + name_len(strbuf, xattr_name_len))) {
 716                                 res = -ERANGE;
 717                                 goto end_listxattr;
 718                         } else
 719                                 res += copy_name(buffer + res,
 720                                                 strbuf, xattr_name_len);
 721                 }
 722
 723                 if (hfs_brec_goto(&fd, 1))
 724                         goto end_listxattr;
 725         }
 726
 727 end_listxattr:
 728         kfree(strbuf);
 729 out:
 730         hfs_find_exit(&fd);
 731         return res;
 732 }
 733
 734 static int hfsplus_removexattr(struct inode *inode, const char *name)
 735 {
 736         int err = 0;
 737         struct hfs_find_data cat_fd;
 738         u16 flags;
 739         u16 cat_entry_type;
 740         int is_xattr_acl_deleted = 0;
 741         int is_all_xattrs_deleted = 0;
 742
 743         if (!HFSPLUS_SB(inode->i_sb)->attr_tree)
 744                 return -EOPNOTSUPP;
 745
 746         if (!strcmp_xattr_finder_info(name))
 747                 return -EOPNOTSUPP;
 748
 749         err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &cat_fd);
 750         if (err) {
 751                 pr_err("can't init xattr find struct\n");
 752                 return err;
 753         }
 754
 755         err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &cat_fd);
 756         if (err) {
 757                 pr_err("catalog searching failed\n");
 758                 goto end_removexattr;
 759         }
 760
 761         err = hfsplus_delete_attr(inode, name);
 762         if (err)
 763                 goto end_removexattr;
 764
 765         is_xattr_acl_deleted = !strcmp_xattr_acl(name);
 766         is_all_xattrs_deleted = !hfsplus_attr_exists(inode, NULL);
 767
 768         if (!is_xattr_acl_deleted && !is_all_xattrs_deleted)
 769                 goto end_removexattr;
 770
 771         cat_entry_type = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset);
 772
 773         if (cat_entry_type == HFSPLUS_FOLDER) {
 774                 flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
 775                                 offsetof(struct hfsplus_cat_folder, flags));
 776                 if (is_xattr_acl_deleted)
 777                         flags &= ~HFSPLUS_ACL_EXISTS;
 778                 if (is_all_xattrs_deleted)
 779                         flags &= ~HFSPLUS_XATTR_EXISTS;
 780                 hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 781                                 offsetof(struct hfsplus_cat_folder, flags),
 782                                 flags);
 783                 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 784         } else if (cat_entry_type == HFSPLUS_FILE) {
 785                 flags = hfs_bnode_read_u16(cat_fd.bnode, cat_fd.entryoffset +
 786                                 offsetof(struct hfsplus_cat_file, flags));
 787                 if (is_xattr_acl_deleted)
 788                         flags &= ~HFSPLUS_ACL_EXISTS;
 789                 if (is_all_xattrs_deleted)
 790                         flags &= ~HFSPLUS_XATTR_EXISTS;
 791                 hfs_bnode_write_u16(cat_fd.bnode, cat_fd.entryoffset +
 792                                 offsetof(struct hfsplus_cat_file, flags),
 793                                 flags);
 794                 hfsplus_mark_inode_dirty(inode, HFSPLUS_I_CAT_DIRTY);
 795         } else {
 796                 pr_err("invalid catalog entry type\n");
 797                 err = -EIO;
 798                 goto end_removexattr;
 799         }
 800
 801 end_removexattr:
 802         hfs_find_exit(&cat_fd);
 803         return err;
 804 }
 805
 806 static int hfsplus_osx_getxattr(struct dentry *dentry, const char *name,
 807                                         void *buffer, size_t size, int type)
 808 {
 809         char *xattr_name;
 810         int res;
 811
 812         if (!strcmp(name, ""))
 813                 return -EINVAL;
 814
 815         /*
 816          * Don't allow retrieving properly prefixed attributes
 817          * by prepending them with "osx."
 818          */
 819         if (is_known_namespace(name))
 820                 return -EOPNOTSUPP;
 821         xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN
 822                 + XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
 823         if (!xattr_name)
 824                 return -ENOMEM;
 825         strcpy(xattr_name, XATTR_MAC_OSX_PREFIX);
 826         strcpy(xattr_name + XATTR_MAC_OSX_PREFIX_LEN, name);
 827
 828         res = hfsplus_getxattr(dentry, xattr_name, buffer, size);
 829         kfree(xattr_name);
 830         return res;
 831 }
 832
 833 static int hfsplus_osx_setxattr(struct dentry *dentry, const char *name,
 834                 const void *buffer, size_t size, int flags, int type)
 835 {
 836         char *xattr_name;
 837         int res;
 838
 839         if (!strcmp(name, ""))
 840                 return -EINVAL;
 841
 842         /*
 843          * Don't allow setting properly prefixed attributes
 844          * by prepending them with "osx."
 845          */
 846         if (is_known_namespace(name))
 847                 return -EOPNOTSUPP;
 848         xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN
 849                 + XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
 850         if (!xattr_name)
 851                 return -ENOMEM;
 852         strcpy(xattr_name, XATTR_MAC_OSX_PREFIX);
 853         strcpy(xattr_name + XATTR_MAC_OSX_PREFIX_LEN, name);
 854
 855         res = hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
 856         kfree(xattr_name);
 857         return res;
 858 }
 859
 860 static size_t hfsplus_osx_listxattr(struct dentry *dentry, char *list,
 861                 size_t list_size, const char *name, size_t name_len, int type)
 862 {
 863         /*
 864          * This method is not used.
 865          * It is used hfsplus_listxattr() instead of generic_listxattr().
 866          */
 867         return -EOPNOTSUPP;
 868 }
 869
 870 const struct xattr_handler hfsplus_xattr_osx_handler = {
 871         .prefix = XATTR_MAC_OSX_PREFIX,
 872         .list   = hfsplus_osx_listxattr,
 873         .get    = hfsplus_osx_getxattr,
 874         .set    = hfsplus_osx_setxattr,
 875 };