1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 *
4 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5 *
6 */
7
8 #include <linux/fs.h>
9 #include <linux/nls.h>
10 #include <linux/ctype.h>
11 #include <linux/posix_acl.h>
12
13 #include "debug.h"
14 #include "ntfs.h"
15 #include "ntfs_fs.h"
16
17 /*
18 * fill_name_de - Format NTFS_DE in @buf.
19 */
fill_name_de(struct ntfs_sb_info * sbi,void * buf,const struct qstr * name,const struct cpu_str * uni)20 int fill_name_de(struct ntfs_sb_info *sbi, void *buf, const struct qstr *name,
21 const struct cpu_str *uni)
22 {
23 int err;
24 struct NTFS_DE *e = buf;
25 u16 data_size;
26 struct ATTR_FILE_NAME *fname = (struct ATTR_FILE_NAME *)(e + 1);
27
28 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
29 e->ref.high = fname->home.high = 0;
30 #endif
31 if (uni) {
32 #ifdef __BIG_ENDIAN
33 int ulen = uni->len;
34 __le16 *uname = fname->name;
35 const u16 *name_cpu = uni->name;
36
37 while (ulen--)
38 *uname++ = cpu_to_le16(*name_cpu++);
39 #else
40 memcpy(fname->name, uni->name, uni->len * sizeof(u16));
41 #endif
42 fname->name_len = uni->len;
43
44 } else {
45 /* Convert input string to unicode. */
46 err = ntfs_nls_to_utf16(sbi, name->name, name->len,
47 (struct cpu_str *)&fname->name_len,
48 NTFS_NAME_LEN, UTF16_LITTLE_ENDIAN);
49 if (err < 0)
50 return err;
51 }
52
53 fname->type = FILE_NAME_POSIX;
54 data_size = fname_full_size(fname);
55
56 e->size = cpu_to_le16(ALIGN(data_size, 8) + sizeof(struct NTFS_DE));
57 e->key_size = cpu_to_le16(data_size);
58 e->flags = 0;
59 e->res = 0;
60
61 return 0;
62 }
63
64 /*
65 * ntfs_lookup - inode_operations::lookup
66 */
ntfs_lookup(struct inode * dir,struct dentry * dentry,u32 flags)67 static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
68 u32 flags)
69 {
70 struct ntfs_inode *ni = ntfs_i(dir);
71 struct cpu_str *uni = __getname();
72 struct inode *inode;
73 int err;
74
75 if (!uni)
76 inode = ERR_PTR(-ENOMEM);
77 else {
78 err = ntfs_nls_to_utf16(ni->mi.sbi, dentry->d_name.name,
79 dentry->d_name.len, uni, NTFS_NAME_LEN,
80 UTF16_HOST_ENDIAN);
81 if (err < 0)
82 inode = ERR_PTR(err);
83 else {
84 ni_lock(ni);
85 inode = dir_search_u(dir, uni, NULL);
86 ni_unlock(ni);
87 }
88 __putname(uni);
89 }
90
91 /*
92 * Check for a null pointer
93 * If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL.
94 * This causes null pointer dereference in d_splice_alias().
95 */
96 if (!IS_ERR_OR_NULL(inode) && !inode->i_op) {
97 iput(inode);
98 inode = ERR_PTR(-EINVAL);
99 }
100
101 return d_splice_alias(inode, dentry);
102 }
103
104 /*
105 * ntfs_create - inode_operations::create
106 */
ntfs_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,bool excl)107 static int ntfs_create(struct mnt_idmap *idmap, struct inode *dir,
108 struct dentry *dentry, umode_t mode, bool excl)
109 {
110 struct inode *inode;
111
112 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFREG | mode, 0,
113 NULL, 0, NULL);
114
115 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
116 }
117
118 /*
119 * ntfs_mknod
120 *
121 * inode_operations::mknod
122 */
ntfs_mknod(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)123 static int ntfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
124 struct dentry *dentry, umode_t mode, dev_t rdev)
125 {
126 struct inode *inode;
127
128 inode = ntfs_create_inode(idmap, dir, dentry, NULL, mode, rdev, NULL, 0,
129 NULL);
130
131 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
132 }
133
134 /*
135 * ntfs_link - inode_operations::link
136 */
ntfs_link(struct dentry * ode,struct inode * dir,struct dentry * de)137 static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
138 {
139 int err;
140 struct inode *inode = d_inode(ode);
141 struct ntfs_inode *ni = ntfs_i(inode);
142
143 if (S_ISDIR(inode->i_mode))
144 return -EPERM;
145
146 if (inode->i_nlink >= NTFS_LINK_MAX)
147 return -EMLINK;
148
149 ni_lock_dir(ntfs_i(dir));
150 if (inode != dir)
151 ni_lock(ni);
152
153 inc_nlink(inode);
154 ihold(inode);
155
156 err = ntfs_link_inode(inode, de);
157
158 if (!err) {
159 dir->i_mtime = inode_set_ctime_to_ts(
160 inode, inode_set_ctime_current(dir));
161 mark_inode_dirty(inode);
162 mark_inode_dirty(dir);
163 d_instantiate(de, inode);
164 } else {
165 drop_nlink(inode);
166 iput(inode);
167 }
168
169 if (inode != dir)
170 ni_unlock(ni);
171 ni_unlock(ntfs_i(dir));
172
173 return err;
174 }
175
176 /*
177 * ntfs_unlink - inode_operations::unlink
178 */
ntfs_unlink(struct inode * dir,struct dentry * dentry)179 static int ntfs_unlink(struct inode *dir, struct dentry *dentry)
180 {
181 struct ntfs_inode *ni = ntfs_i(dir);
182 int err;
183
184 ni_lock_dir(ni);
185
186 err = ntfs_unlink_inode(dir, dentry);
187
188 ni_unlock(ni);
189
190 return err;
191 }
192
193 /*
194 * ntfs_symlink - inode_operations::symlink
195 */
ntfs_symlink(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const char * symname)196 static int ntfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
197 struct dentry *dentry, const char *symname)
198 {
199 u32 size = strlen(symname);
200 struct inode *inode;
201
202 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFLNK | 0777, 0,
203 symname, size, NULL);
204
205 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
206 }
207
208 /*
209 * ntfs_mkdir- inode_operations::mkdir
210 */
ntfs_mkdir(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)211 static int ntfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
212 struct dentry *dentry, umode_t mode)
213 {
214 struct inode *inode;
215
216 inode = ntfs_create_inode(idmap, dir, dentry, NULL, S_IFDIR | mode, 0,
217 NULL, 0, NULL);
218
219 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
220 }
221
222 /*
223 * ntfs_rmdir - inode_operations::rmdir
224 */
ntfs_rmdir(struct inode * dir,struct dentry * dentry)225 static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
226 {
227 struct ntfs_inode *ni = ntfs_i(dir);
228 int err;
229
230 ni_lock_dir(ni);
231
232 err = ntfs_unlink_inode(dir, dentry);
233
234 ni_unlock(ni);
235
236 return err;
237 }
238
239 /*
240 * ntfs_rename - inode_operations::rename
241 */
ntfs_rename(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,struct inode * new_dir,struct dentry * new_dentry,u32 flags)242 static int ntfs_rename(struct mnt_idmap *idmap, struct inode *dir,
243 struct dentry *dentry, struct inode *new_dir,
244 struct dentry *new_dentry, u32 flags)
245 {
246 int err;
247 struct super_block *sb = dir->i_sb;
248 struct ntfs_sb_info *sbi = sb->s_fs_info;
249 struct ntfs_inode *dir_ni = ntfs_i(dir);
250 struct ntfs_inode *new_dir_ni = ntfs_i(new_dir);
251 struct inode *inode = d_inode(dentry);
252 struct ntfs_inode *ni = ntfs_i(inode);
253 struct inode *new_inode = d_inode(new_dentry);
254 struct NTFS_DE *de, *new_de;
255 bool is_same, is_bad;
256 /*
257 * de - memory of PATH_MAX bytes:
258 * [0-1024) - original name (dentry->d_name)
259 * [1024-2048) - paired to original name, usually DOS variant of dentry->d_name
260 * [2048-3072) - new name (new_dentry->d_name)
261 */
262 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
263 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
264 1024);
265 static_assert(PATH_MAX >= 4 * 1024);
266
267 if (flags & ~RENAME_NOREPLACE)
268 return -EINVAL;
269
270 is_same = dentry->d_name.len == new_dentry->d_name.len &&
271 !memcmp(dentry->d_name.name, new_dentry->d_name.name,
272 dentry->d_name.len);
273
274 if (is_same && dir == new_dir) {
275 /* Nothing to do. */
276 return 0;
277 }
278
279 if (ntfs_is_meta_file(sbi, inode->i_ino)) {
280 /* Should we print an error? */
281 return -EINVAL;
282 }
283
284 if (new_inode) {
285 /* Target name exists. Unlink it. */
286 dget(new_dentry);
287 ni_lock_dir(new_dir_ni);
288 err = ntfs_unlink_inode(new_dir, new_dentry);
289 ni_unlock(new_dir_ni);
290 dput(new_dentry);
291 if (err)
292 return err;
293 }
294
295 /* Allocate PATH_MAX bytes. */
296 de = __getname();
297 if (!de)
298 return -ENOMEM;
299
300 /* Translate dentry->d_name into unicode form. */
301 err = fill_name_de(sbi, de, &dentry->d_name, NULL);
302 if (err < 0)
303 goto out;
304
305 if (is_same) {
306 /* Reuse 'de'. */
307 new_de = de;
308 } else {
309 /* Translate new_dentry->d_name into unicode form. */
310 new_de = Add2Ptr(de, 2048);
311 err = fill_name_de(sbi, new_de, &new_dentry->d_name, NULL);
312 if (err < 0)
313 goto out;
314 }
315
316 ni_lock_dir(dir_ni);
317 ni_lock(ni);
318 if (dir_ni != new_dir_ni)
319 ni_lock_dir2(new_dir_ni);
320
321 is_bad = false;
322 err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de, &is_bad);
323 if (is_bad) {
324 /* Restore after failed rename failed too. */
325 _ntfs_bad_inode(inode);
326 } else if (!err) {
327 simple_rename_timestamp(dir, dentry, new_dir, new_dentry);
328 mark_inode_dirty(inode);
329 mark_inode_dirty(dir);
330 if (dir != new_dir)
331 mark_inode_dirty(new_dir);
332
333 if (IS_DIRSYNC(dir))
334 ntfs_sync_inode(dir);
335
336 if (IS_DIRSYNC(new_dir))
337 ntfs_sync_inode(inode);
338 }
339
340 if (dir_ni != new_dir_ni)
341 ni_unlock(new_dir_ni);
342 ni_unlock(ni);
343 ni_unlock(dir_ni);
344 out:
345 __putname(de);
346 return err;
347 }
348
349 /*
350 * ntfs_atomic_open
351 *
352 * inode_operations::atomic_open
353 */
ntfs_atomic_open(struct inode * dir,struct dentry * dentry,struct file * file,u32 flags,umode_t mode)354 static int ntfs_atomic_open(struct inode *dir, struct dentry *dentry,
355 struct file *file, u32 flags, umode_t mode)
356 {
357 int err;
358 struct inode *inode;
359 struct ntfs_fnd *fnd = NULL;
360 struct ntfs_inode *ni = ntfs_i(dir);
361 struct dentry *d = NULL;
362 struct cpu_str *uni = __getname();
363 bool locked = false;
364
365 if (!uni)
366 return -ENOMEM;
367
368 err = ntfs_nls_to_utf16(ni->mi.sbi, dentry->d_name.name,
369 dentry->d_name.len, uni, NTFS_NAME_LEN,
370 UTF16_HOST_ENDIAN);
371 if (err < 0)
372 goto out;
373
374 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
375 if (IS_POSIXACL(dir)) {
376 /*
377 * Load in cache current acl to avoid ni_lock(dir):
378 * ntfs_create_inode -> ntfs_init_acl -> posix_acl_create ->
379 * ntfs_get_acl -> ntfs_get_acl_ex -> ni_lock
380 */
381 struct posix_acl *p = get_inode_acl(dir, ACL_TYPE_DEFAULT);
382
383 if (IS_ERR(p)) {
384 err = PTR_ERR(p);
385 goto out;
386 }
387 posix_acl_release(p);
388 }
389 #endif
390
391 if (d_in_lookup(dentry)) {
392 ni_lock_dir(ni);
393 locked = true;
394 fnd = fnd_get();
395 if (!fnd) {
396 err = -ENOMEM;
397 goto out1;
398 }
399
400 d = d_splice_alias(dir_search_u(dir, uni, fnd), dentry);
401 if (IS_ERR(d)) {
402 err = PTR_ERR(d);
403 d = NULL;
404 goto out2;
405 }
406
407 if (d)
408 dentry = d;
409 }
410
411 if (!(flags & O_CREAT) || d_really_is_positive(dentry)) {
412 err = finish_no_open(file, d);
413 goto out2;
414 }
415
416 file->f_mode |= FMODE_CREATED;
417
418 /*
419 * fnd contains tree's path to insert to.
420 * If fnd is not NULL then dir is locked.
421 */
422 inode = ntfs_create_inode(mnt_idmap(file->f_path.mnt), dir, dentry, uni,
423 mode, 0, NULL, 0, fnd);
424 err = IS_ERR(inode) ? PTR_ERR(inode) :
425 finish_open(file, dentry, ntfs_file_open);
426 dput(d);
427
428 out2:
429 fnd_put(fnd);
430 out1:
431 if (locked)
432 ni_unlock(ni);
433 out:
434 __putname(uni);
435 return err;
436 }
437
ntfs3_get_parent(struct dentry * child)438 struct dentry *ntfs3_get_parent(struct dentry *child)
439 {
440 struct inode *inode = d_inode(child);
441 struct ntfs_inode *ni = ntfs_i(inode);
442
443 struct ATTR_LIST_ENTRY *le = NULL;
444 struct ATTRIB *attr = NULL;
445 struct ATTR_FILE_NAME *fname;
446
447 while ((attr = ni_find_attr(ni, attr, &le, ATTR_NAME, NULL, 0, NULL,
448 NULL))) {
449 fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
450 if (!fname)
451 continue;
452
453 return d_obtain_alias(
454 ntfs_iget5(inode->i_sb, &fname->home, NULL));
455 }
456
457 return ERR_PTR(-ENOENT);
458 }
459
460 /*
461 * dentry_operations::d_hash
462 */
ntfs_d_hash(const struct dentry * dentry,struct qstr * name)463 static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name)
464 {
465 struct ntfs_sb_info *sbi;
466 const char *n = name->name;
467 unsigned int len = name->len;
468 unsigned long hash;
469 struct cpu_str *uni;
470 unsigned int c;
471 int err;
472
473 /* First try fast implementation. */
474 hash = init_name_hash(dentry);
475
476 for (;;) {
477 if (!len--) {
478 name->hash = end_name_hash(hash);
479 return 0;
480 }
481
482 c = *n++;
483 if (c >= 0x80)
484 break;
485
486 hash = partial_name_hash(toupper(c), hash);
487 }
488
489 /*
490 * Try slow way with current upcase table
491 */
492 uni = __getname();
493 if (!uni)
494 return -ENOMEM;
495
496 sbi = dentry->d_sb->s_fs_info;
497
498 err = ntfs_nls_to_utf16(sbi, name->name, name->len, uni, NTFS_NAME_LEN,
499 UTF16_HOST_ENDIAN);
500 if (err < 0)
501 goto out;
502
503 if (!err) {
504 err = -EINVAL;
505 goto out;
506 }
507
508 hash = ntfs_names_hash(uni->name, uni->len, sbi->upcase,
509 init_name_hash(dentry));
510 name->hash = end_name_hash(hash);
511 err = 0;
512
513 out:
514 __putname(uni);
515 return err;
516 }
517
518 /*
519 * dentry_operations::d_compare
520 */
ntfs_d_compare(const struct dentry * dentry,unsigned int len1,const char * str,const struct qstr * name)521 static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
522 const char *str, const struct qstr *name)
523 {
524 struct ntfs_sb_info *sbi;
525 int ret;
526 const char *n1 = str;
527 const char *n2 = name->name;
528 unsigned int len2 = name->len;
529 unsigned int lm = min(len1, len2);
530 unsigned char c1, c2;
531 struct cpu_str *uni1;
532 struct le_str *uni2;
533
534 /* First try fast implementation. */
535 for (;;) {
536 if (!lm--)
537 return len1 != len2;
538
539 if ((c1 = *n1++) == (c2 = *n2++))
540 continue;
541
542 if (c1 >= 0x80 || c2 >= 0x80)
543 break;
544
545 if (toupper(c1) != toupper(c2))
546 return 1;
547 }
548
549 /*
550 * Try slow way with current upcase table
551 */
552 sbi = dentry->d_sb->s_fs_info;
553 uni1 = __getname();
554 if (!uni1)
555 return -ENOMEM;
556
557 ret = ntfs_nls_to_utf16(sbi, str, len1, uni1, NTFS_NAME_LEN,
558 UTF16_HOST_ENDIAN);
559 if (ret < 0)
560 goto out;
561
562 if (!ret) {
563 ret = -EINVAL;
564 goto out;
565 }
566
567 uni2 = Add2Ptr(uni1, 2048);
568
569 ret = ntfs_nls_to_utf16(sbi, name->name, name->len,
570 (struct cpu_str *)uni2, NTFS_NAME_LEN,
571 UTF16_LITTLE_ENDIAN);
572 if (ret < 0)
573 goto out;
574
575 if (!ret) {
576 ret = -EINVAL;
577 goto out;
578 }
579
580 ret = !ntfs_cmp_names_cpu(uni1, uni2, sbi->upcase, false) ? 0 : 1;
581
582 out:
583 __putname(uni1);
584 return ret;
585 }
586
587 // clang-format off
588 const struct inode_operations ntfs_dir_inode_operations = {
589 .lookup = ntfs_lookup,
590 .create = ntfs_create,
591 .link = ntfs_link,
592 .unlink = ntfs_unlink,
593 .symlink = ntfs_symlink,
594 .mkdir = ntfs_mkdir,
595 .rmdir = ntfs_rmdir,
596 .mknod = ntfs_mknod,
597 .rename = ntfs_rename,
598 .get_acl = ntfs_get_acl,
599 .set_acl = ntfs_set_acl,
600 .setattr = ntfs3_setattr,
601 .getattr = ntfs_getattr,
602 .listxattr = ntfs_listxattr,
603 .atomic_open = ntfs_atomic_open,
604 .fiemap = ntfs_fiemap,
605 };
606
607 const struct inode_operations ntfs_special_inode_operations = {
608 .setattr = ntfs3_setattr,
609 .getattr = ntfs_getattr,
610 .listxattr = ntfs_listxattr,
611 .get_acl = ntfs_get_acl,
612 .set_acl = ntfs_set_acl,
613 };
614
615 const struct dentry_operations ntfs_dentry_ops = {
616 .d_hash = ntfs_d_hash,
617 .d_compare = ntfs_d_compare,
618 };
619
620 // clang-format on
621
