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_set_ctime_current(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_set_ctime_current(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_set_ctime_current(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 mnt_idmap *idmap, 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 mnt_idmap *idmap, 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 mnt_idmap *idmap, struct inode *dir,
521 struct dentry *dentry, umode_t mode, bool excl)
522 {
523 return hfsplus_mknod(&nop_mnt_idmap, dir, dentry, mode, 0);
524 }
525
526 static int hfsplus_mkdir(struct mnt_idmap *idmap, struct inode *dir,
527 struct dentry *dentry, umode_t mode)
528 {
529 return hfsplus_mknod(&nop_mnt_idmap, dir, dentry, mode | S_IFDIR, 0);
530 }
531
532 static int hfsplus_rename(struct mnt_idmap *idmap,
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 .fileattr_get = hfsplus_fileattr_get,
573 .fileattr_set = hfsplus_fileattr_set,
574 };
575
576 const struct file_operations hfsplus_dir_operations = {
577 .fsync = hfsplus_file_fsync,
578 .read = generic_read_dir,
579 .iterate_shared = hfsplus_readdir,
580 .unlocked_ioctl = hfsplus_ioctl,
581 .llseek = generic_file_llseek,
582 .release = hfsplus_dir_release,
583 };
584
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