1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * linux/fs/hfsplus/dir.c 4 * 5 * Copyright (C) 2001 6 * Brad Boyer (flar@allandria.com) 7 * (C) 2003 Ardis Technologies <roman@ardistech.com> 8 * 9 * Handling of directories 10 */ 11 12 #include <linux/errno.h> 13 #include <linux/fs.h> 14 #include <linux/slab.h> 15 #include <linux/random.h> 16 #include <linux/nls.h> 17 18 #include "hfsplus_fs.h" 19 #include "hfsplus_raw.h" 20 #include "xattr.h" 21 22 static inline void hfsplus_instantiate(struct dentry *dentry, 23 struct inode *inode, u32 cnid) 24 { 25 dentry->d_fsdata = (void *)(unsigned long)cnid; 26 d_instantiate(dentry, inode); 27 } 28 29 /* Find the entry inside dir named dentry->d_name */ 30 static struct dentry *hfsplus_lookup(struct inode *dir, struct dentry *dentry, 31 unsigned int flags) 32 { 33 struct inode *inode = NULL; 34 struct hfs_find_data fd; 35 struct super_block *sb; 36 hfsplus_cat_entry entry; 37 int err; 38 u32 cnid, linkid = 0; 39 u16 type; 40 41 sb = dir->i_sb; 42 43 dentry->d_fsdata = NULL; 44 err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd); 45 if (err) 46 return ERR_PTR(err); 47 err = hfsplus_cat_build_key(sb, fd.search_key, dir->i_ino, 48 &dentry->d_name); 49 if (unlikely(err < 0)) 50 goto fail; 51 again: 52 err = hfs_brec_read(&fd, &entry, sizeof(entry)); 53 if (err) { 54 if (err == -ENOENT) { 55 hfs_find_exit(&fd); 56 /* No such entry */ 57 inode = NULL; 58 goto out; 59 } 60 goto fail; 61 } 62 type = be16_to_cpu(entry.type); 63 if (type == HFSPLUS_FOLDER) { 64 if (fd.entrylength < sizeof(struct hfsplus_cat_folder)) { 65 err = -EIO; 66 goto fail; 67 } 68 cnid = be32_to_cpu(entry.folder.id); 69 dentry->d_fsdata = (void *)(unsigned long)cnid; 70 } else if (type == HFSPLUS_FILE) { 71 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) { 72 err = -EIO; 73 goto fail; 74 } 75 cnid = be32_to_cpu(entry.file.id); 76 if (entry.file.user_info.fdType == 77 cpu_to_be32(HFSP_HARDLINK_TYPE) && 78 entry.file.user_info.fdCreator == 79 cpu_to_be32(HFSP_HFSPLUS_CREATOR) && 80 HFSPLUS_SB(sb)->hidden_dir && 81 (entry.file.create_date == 82 HFSPLUS_I(HFSPLUS_SB(sb)->hidden_dir)-> 83 create_date || 84 entry.file.create_date == 85 HFSPLUS_I(d_inode(sb->s_root))-> 86 create_date)) { 87 struct qstr str; 88 char name[32]; 89 90 if (dentry->d_fsdata) { 91 /* 92 * We found a link pointing to another link, 93 * so ignore it and treat it as regular file. 94 */ 95 cnid = (unsigned long)dentry->d_fsdata; 96 linkid = 0; 97 } else { 98 dentry->d_fsdata = (void *)(unsigned long)cnid; 99 linkid = 100 be32_to_cpu(entry.file.permissions.dev); 101 str.len = sprintf(name, "iNode%d", linkid); 102 str.name = name; 103 err = hfsplus_cat_build_key(sb, fd.search_key, 104 HFSPLUS_SB(sb)->hidden_dir->i_ino, 105 &str); 106 if (unlikely(err < 0)) 107 goto fail; 108 goto again; 109 } 110 } else if (!dentry->d_fsdata) 111 dentry->d_fsdata = (void *)(unsigned long)cnid; 112 } else { 113 pr_err("invalid catalog entry type in lookup\n"); 114 err = -EIO; 115 goto fail; 116 } 117 hfs_find_exit(&fd); 118 inode = hfsplus_iget(dir->i_sb, cnid); 119 if (IS_ERR(inode)) 120 return ERR_CAST(inode); 121 if (S_ISREG(inode->i_mode)) 122 HFSPLUS_I(inode)->linkid = linkid; 123 out: 124 return d_splice_alias(inode, dentry); 125 fail: 126 hfs_find_exit(&fd); 127 return ERR_PTR(err); 128 } 129 130 static int hfsplus_readdir(struct file *file, struct dir_context *ctx) 131 { 132 struct inode *inode = file_inode(file); 133 struct super_block *sb = inode->i_sb; 134 int len, err; 135 char *strbuf; 136 hfsplus_cat_entry entry; 137 struct hfs_find_data fd; 138 struct hfsplus_readdir_data *rd; 139 u16 type; 140 141 if (file->f_pos >= inode->i_size) 142 return 0; 143 144 err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd); 145 if (err) 146 return err; 147 strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN + 1, GFP_KERNEL); 148 if (!strbuf) { 149 err = -ENOMEM; 150 goto out; 151 } 152 hfsplus_cat_build_key_with_cnid(sb, fd.search_key, inode->i_ino); 153 err = hfs_brec_find(&fd, hfs_find_rec_by_key); 154 if (err) 155 goto out; 156 157 if (ctx->pos == 0) { 158 /* This is completely artificial... */ 159 if (!dir_emit_dot(file, ctx)) 160 goto out; 161 ctx->pos = 1; 162 } 163 if (ctx->pos == 1) { 164 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) { 165 err = -EIO; 166 goto out; 167 } 168 169 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, 170 fd.entrylength); 171 if (be16_to_cpu(entry.type) != HFSPLUS_FOLDER_THREAD) { 172 pr_err("bad catalog folder thread\n"); 173 err = -EIO; 174 goto out; 175 } 176 if (fd.entrylength < HFSPLUS_MIN_THREAD_SZ) { 177 pr_err("truncated catalog thread\n"); 178 err = -EIO; 179 goto out; 180 } 181 if (!dir_emit(ctx, "..", 2, 182 be32_to_cpu(entry.thread.parentID), DT_DIR)) 183 goto out; 184 ctx->pos = 2; 185 } 186 if (ctx->pos >= inode->i_size) 187 goto out; 188 err = hfs_brec_goto(&fd, ctx->pos - 1); 189 if (err) 190 goto out; 191 for (;;) { 192 if (be32_to_cpu(fd.key->cat.parent) != inode->i_ino) { 193 pr_err("walked past end of dir\n"); 194 err = -EIO; 195 goto out; 196 } 197 198 if (fd.entrylength > sizeof(entry) || fd.entrylength < 0) { 199 err = -EIO; 200 goto out; 201 } 202 203 hfs_bnode_read(fd.bnode, &entry, fd.entryoffset, 204 fd.entrylength); 205 type = be16_to_cpu(entry.type); 206 len = NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN; 207 err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len); 208 if (err) 209 goto out; 210 if (type == HFSPLUS_FOLDER) { 211 if (fd.entrylength < 212 sizeof(struct hfsplus_cat_folder)) { 213 pr_err("small dir entry\n"); 214 err = -EIO; 215 goto out; 216 } 217 if (HFSPLUS_SB(sb)->hidden_dir && 218 HFSPLUS_SB(sb)->hidden_dir->i_ino == 219 be32_to_cpu(entry.folder.id)) 220 goto next; 221 if (!dir_emit(ctx, strbuf, len, 222 be32_to_cpu(entry.folder.id), DT_DIR)) 223 break; 224 } else if (type == HFSPLUS_FILE) { 225 u16 mode; 226 unsigned type = DT_UNKNOWN; 227 228 if (fd.entrylength < sizeof(struct hfsplus_cat_file)) { 229 pr_err("small file entry\n"); 230 err = -EIO; 231 goto out; 232 } 233 234 mode = be16_to_cpu(entry.file.permissions.mode); 235 if (S_ISREG(mode)) 236 type = DT_REG; 237 else if (S_ISLNK(mode)) 238 type = DT_LNK; 239 else if (S_ISFIFO(mode)) 240 type = DT_FIFO; 241 else if (S_ISCHR(mode)) 242 type = DT_CHR; 243 else if (S_ISBLK(mode)) 244 type = DT_BLK; 245 else if (S_ISSOCK(mode)) 246 type = DT_SOCK; 247 248 if (!dir_emit(ctx, strbuf, len, 249 be32_to_cpu(entry.file.id), type)) 250 break; 251 } else { 252 pr_err("bad catalog entry type\n"); 253 err = -EIO; 254 goto out; 255 } 256 next: 257 ctx->pos++; 258 if (ctx->pos >= inode->i_size) 259 goto out; 260 err = hfs_brec_goto(&fd, 1); 261 if (err) 262 goto out; 263 } 264 rd = file->private_data; 265 if (!rd) { 266 rd = kmalloc(sizeof(struct hfsplus_readdir_data), GFP_KERNEL); 267 if (!rd) { 268 err = -ENOMEM; 269 goto out; 270 } 271 file->private_data = rd; 272 rd->file = file; 273 spin_lock(&HFSPLUS_I(inode)->open_dir_lock); 274 list_add(&rd->list, &HFSPLUS_I(inode)->open_dir_list); 275 spin_unlock(&HFSPLUS_I(inode)->open_dir_lock); 276 } 277 /* 278 * Can be done after the list insertion; exclusion with 279 * hfsplus_delete_cat() is provided by directory lock. 280 */ 281 memcpy(&rd->key, fd.key, sizeof(struct hfsplus_cat_key)); 282 out: 283 kfree(strbuf); 284 hfs_find_exit(&fd); 285 return err; 286 } 287 288 static int hfsplus_dir_release(struct inode *inode, struct file *file) 289 { 290 struct hfsplus_readdir_data *rd = file->private_data; 291 if (rd) { 292 spin_lock(&HFSPLUS_I(inode)->open_dir_lock); 293 list_del(&rd->list); 294 spin_unlock(&HFSPLUS_I(inode)->open_dir_lock); 295 kfree(rd); 296 } 297 return 0; 298 } 299 300 static int hfsplus_link(struct dentry *src_dentry, struct inode *dst_dir, 301 struct dentry *dst_dentry) 302 { 303 struct hfsplus_sb_info *sbi = HFSPLUS_SB(dst_dir->i_sb); 304 struct inode *inode = d_inode(src_dentry); 305 struct inode *src_dir = d_inode(src_dentry->d_parent); 306 struct qstr str; 307 char name[32]; 308 u32 cnid, id; 309 int res; 310 311 if (HFSPLUS_IS_RSRC(inode)) 312 return -EPERM; 313 if (!S_ISREG(inode->i_mode)) 314 return -EPERM; 315 316 mutex_lock(&sbi->vh_mutex); 317 if (inode->i_ino == (u32)(unsigned long)src_dentry->d_fsdata) { 318 for (;;) { 319 get_random_bytes(&id, sizeof(cnid)); 320 id &= 0x3fffffff; 321 str.name = name; 322 str.len = sprintf(name, "iNode%d", id); 323 res = hfsplus_rename_cat(inode->i_ino, 324 src_dir, &src_dentry->d_name, 325 sbi->hidden_dir, &str); 326 if (!res) 327 break; 328 if (res != -EEXIST) 329 goto out; 330 } 331 HFSPLUS_I(inode)->linkid = id; 332 cnid = sbi->next_cnid++; 333 src_dentry->d_fsdata = (void *)(unsigned long)cnid; 334 res = hfsplus_create_cat(cnid, src_dir, 335 &src_dentry->d_name, inode); 336 if (res) 337 /* panic? */ 338 goto out; 339 sbi->file_count++; 340 } 341 cnid = sbi->next_cnid++; 342 res = hfsplus_create_cat(cnid, dst_dir, &dst_dentry->d_name, inode); 343 if (res) 344 goto out; 345 346 inc_nlink(inode); 347 hfsplus_instantiate(dst_dentry, inode, cnid); 348 ihold(inode); 349 inode->i_ctime = current_time(inode); 350 mark_inode_dirty(inode); 351 sbi->file_count++; 352 hfsplus_mark_mdb_dirty(dst_dir->i_sb); 353 out: 354 mutex_unlock(&sbi->vh_mutex); 355 return res; 356 } 357 358 static int hfsplus_unlink(struct inode *dir, struct dentry *dentry) 359 { 360 struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb); 361 struct inode *inode = d_inode(dentry); 362 struct qstr str; 363 char name[32]; 364 u32 cnid; 365 int res; 366 367 if (HFSPLUS_IS_RSRC(inode)) 368 return -EPERM; 369 370 mutex_lock(&sbi->vh_mutex); 371 cnid = (u32)(unsigned long)dentry->d_fsdata; 372 if (inode->i_ino == cnid && 373 atomic_read(&HFSPLUS_I(inode)->opencnt)) { 374 str.name = name; 375 str.len = sprintf(name, "temp%lu", inode->i_ino); 376 res = hfsplus_rename_cat(inode->i_ino, 377 dir, &dentry->d_name, 378 sbi->hidden_dir, &str); 379 if (!res) { 380 inode->i_flags |= S_DEAD; 381 drop_nlink(inode); 382 } 383 goto out; 384 } 385 res = hfsplus_delete_cat(cnid, dir, &dentry->d_name); 386 if (res) 387 goto out; 388 389 if (inode->i_nlink > 0) 390 drop_nlink(inode); 391 if (inode->i_ino == cnid) 392 clear_nlink(inode); 393 if (!inode->i_nlink) { 394 if (inode->i_ino != cnid) { 395 sbi->file_count--; 396 if (!atomic_read(&HFSPLUS_I(inode)->opencnt)) { 397 res = hfsplus_delete_cat(inode->i_ino, 398 sbi->hidden_dir, 399 NULL); 400 if (!res) 401 hfsplus_delete_inode(inode); 402 } else 403 inode->i_flags |= S_DEAD; 404 } else 405 hfsplus_delete_inode(inode); 406 } else 407 sbi->file_count--; 408 inode->i_ctime = current_time(inode); 409 mark_inode_dirty(inode); 410 out: 411 mutex_unlock(&sbi->vh_mutex); 412 return res; 413 } 414 415 static int hfsplus_rmdir(struct inode *dir, struct dentry *dentry) 416 { 417 struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb); 418 struct inode *inode = d_inode(dentry); 419 int res; 420 421 if (inode->i_size != 2) 422 return -ENOTEMPTY; 423 424 mutex_lock(&sbi->vh_mutex); 425 res = hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name); 426 if (res) 427 goto out; 428 clear_nlink(inode); 429 inode->i_ctime = current_time(inode); 430 hfsplus_delete_inode(inode); 431 mark_inode_dirty(inode); 432 out: 433 mutex_unlock(&sbi->vh_mutex); 434 return res; 435 } 436 437 static int hfsplus_symlink(struct user_namespace *mnt_userns, struct inode *dir, 438 struct dentry *dentry, const char *symname) 439 { 440 struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb); 441 struct inode *inode; 442 int res = -ENOMEM; 443 444 mutex_lock(&sbi->vh_mutex); 445 inode = hfsplus_new_inode(dir->i_sb, dir, S_IFLNK | S_IRWXUGO); 446 if (!inode) 447 goto out; 448 449 res = page_symlink(inode, symname, strlen(symname) + 1); 450 if (res) 451 goto out_err; 452 453 res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode); 454 if (res) 455 goto out_err; 456 457 res = hfsplus_init_security(inode, dir, &dentry->d_name); 458 if (res == -EOPNOTSUPP) 459 res = 0; /* Operation is not supported. */ 460 else if (res) { 461 /* Try to delete anyway without error analysis. */ 462 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name); 463 goto out_err; 464 } 465 466 hfsplus_instantiate(dentry, inode, inode->i_ino); 467 mark_inode_dirty(inode); 468 goto out; 469 470 out_err: 471 clear_nlink(inode); 472 hfsplus_delete_inode(inode); 473 iput(inode); 474 out: 475 mutex_unlock(&sbi->vh_mutex); 476 return res; 477 } 478 479 static int hfsplus_mknod(struct user_namespace *mnt_userns, struct inode *dir, 480 struct dentry *dentry, umode_t mode, dev_t rdev) 481 { 482 struct hfsplus_sb_info *sbi = HFSPLUS_SB(dir->i_sb); 483 struct inode *inode; 484 int res = -ENOMEM; 485 486 mutex_lock(&sbi->vh_mutex); 487 inode = hfsplus_new_inode(dir->i_sb, dir, mode); 488 if (!inode) 489 goto out; 490 491 if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISFIFO(mode) || S_ISSOCK(mode)) 492 init_special_inode(inode, mode, rdev); 493 494 res = hfsplus_create_cat(inode->i_ino, dir, &dentry->d_name, inode); 495 if (res) 496 goto failed_mknod; 497 498 res = hfsplus_init_security(inode, dir, &dentry->d_name); 499 if (res == -EOPNOTSUPP) 500 res = 0; /* Operation is not supported. */ 501 else if (res) { 502 /* Try to delete anyway without error analysis. */ 503 hfsplus_delete_cat(inode->i_ino, dir, &dentry->d_name); 504 goto failed_mknod; 505 } 506 507 hfsplus_instantiate(dentry, inode, inode->i_ino); 508 mark_inode_dirty(inode); 509 goto out; 510 511 failed_mknod: 512 clear_nlink(inode); 513 hfsplus_delete_inode(inode); 514 iput(inode); 515 out: 516 mutex_unlock(&sbi->vh_mutex); 517 return res; 518 } 519 520 static int hfsplus_create(struct user_namespace *mnt_userns, struct inode *dir, 521 struct dentry *dentry, umode_t mode, bool excl) 522 { 523 return hfsplus_mknod(&init_user_ns, dir, dentry, mode, 0); 524 } 525 526 static int hfsplus_mkdir(struct user_namespace *mnt_userns, struct inode *dir, 527 struct dentry *dentry, umode_t mode) 528 { 529 return hfsplus_mknod(&init_user_ns, dir, dentry, mode | S_IFDIR, 0); 530 } 531 532 static int hfsplus_rename(struct user_namespace *mnt_userns, 533 struct inode *old_dir, struct dentry *old_dentry, 534 struct inode *new_dir, struct dentry *new_dentry, 535 unsigned int flags) 536 { 537 int res; 538 539 if (flags & ~RENAME_NOREPLACE) 540 return -EINVAL; 541 542 /* Unlink destination if it already exists */ 543 if (d_really_is_positive(new_dentry)) { 544 if (d_is_dir(new_dentry)) 545 res = hfsplus_rmdir(new_dir, new_dentry); 546 else 547 res = hfsplus_unlink(new_dir, new_dentry); 548 if (res) 549 return res; 550 } 551 552 res = hfsplus_rename_cat((u32)(unsigned long)old_dentry->d_fsdata, 553 old_dir, &old_dentry->d_name, 554 new_dir, &new_dentry->d_name); 555 if (!res) 556 new_dentry->d_fsdata = old_dentry->d_fsdata; 557 return res; 558 } 559 560 const struct inode_operations hfsplus_dir_inode_operations = { 561 .lookup = hfsplus_lookup, 562 .create = hfsplus_create, 563 .link = hfsplus_link, 564 .unlink = hfsplus_unlink, 565 .mkdir = hfsplus_mkdir, 566 .rmdir = hfsplus_rmdir, 567 .symlink = hfsplus_symlink, 568 .mknod = hfsplus_mknod, 569 .rename = hfsplus_rename, 570 .getattr = hfsplus_getattr, 571 .listxattr = hfsplus_listxattr, 572 }; 573 574 const struct file_operations hfsplus_dir_operations = { 575 .fsync = hfsplus_file_fsync, 576 .read = generic_read_dir, 577 .iterate_shared = hfsplus_readdir, 578 .unlocked_ioctl = hfsplus_ioctl, 579 .llseek = generic_file_llseek, 580 .release = hfsplus_dir_release, 581 }; 582