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, real_size, aligned_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 real_size = data_size + sizeof(struct NTFS_DE);
57 aligned_size = ALIGN(data_size, 8) + sizeof(struct NTFS_DE);
58 if (aligned_size > real_size)
59 memset((char *)buf + real_size, 0, aligned_size - real_size);
60
61 e->size = cpu_to_le16(aligned_size);
62 e->key_size = cpu_to_le16(data_size);
63 e->flags = 0;
64 e->res = 0;
65
66 return 0;
67 }
68
69 /*
70 * ntfs_lookup - inode_operations::lookup
71 */
ntfs_lookup(struct inode * dir,struct dentry * dentry,u32 flags)72 static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
73 u32 flags)
74 {
75 struct ntfs_inode *ni = ntfs_i(dir);
76 struct cpu_str *uni = kmalloc(PATH_MAX, GFP_KERNEL);
77 struct inode *inode;
78 int err;
79
80 if (!uni)
81 return ERR_PTR(-ENOMEM);
82
83 err = ntfs_nls_to_utf16(ni->mi.sbi, dentry->d_name.name,
84 dentry->d_name.len, uni, NTFS_NAME_LEN,
85 UTF16_HOST_ENDIAN);
86
87 if (err < 0) {
88 kfree(uni);
89 return ERR_PTR(err);
90 }
91
92 ni_lock_dir(ni);
93 inode = dir_search_flags(dir, uni, NULL, flags);
94 ni_unlock(ni);
95
96 kfree(uni);
97
98 /*
99 * Check for a null pointer
100 * If the MFT record of ntfs inode is not a base record, inode->i_op can be NULL.
101 * This causes null pointer dereference in d_splice_alias().
102 */
103 if (!IS_ERR_OR_NULL(inode) && !inode->i_op) {
104 iput(inode);
105 return ERR_PTR(-EINVAL);
106 }
107
108 return d_splice_alias(inode, dentry);
109 }
110
111 /*
112 * ntfs_create - inode_operations::create
113 */
ntfs_create(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)114 static int ntfs_create(struct mnt_idmap *idmap, struct inode *dir,
115 struct dentry *dentry, umode_t mode)
116 {
117 return ntfs_create_inode(idmap, dir, dentry, NULL, S_IFREG | mode, 0,
118 NULL, 0, NULL);
119 }
120
121 /*
122 * ntfs_mknod - inode_operations::mknod
123 */
ntfs_mknod(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)124 static int ntfs_mknod(struct mnt_idmap *idmap, struct inode *dir,
125 struct dentry *dentry, umode_t mode, dev_t rdev)
126 {
127 return ntfs_create_inode(idmap, dir, dentry, NULL, mode, rdev, NULL, 0,
128 NULL);
129 }
130
131 /*
132 * ntfs_link - inode_operations::link
133 */
ntfs_link(struct dentry * ode,struct inode * dir,struct dentry * de)134 static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
135 {
136 int err;
137 struct inode *inode = d_inode(ode);
138 struct ntfs_inode *ni = ntfs_i(inode);
139
140 if (S_ISDIR(inode->i_mode))
141 return -EPERM;
142
143 if (inode->i_nlink >= NTFS_LINK_MAX)
144 return -EMLINK;
145
146 ni_lock_dir(ntfs_i(dir));
147 if (inode != dir)
148 ni_lock(ni);
149
150 inc_nlink(inode);
151 ihold(inode);
152
153 err = ntfs_link_inode(inode, de);
154
155 if (!err) {
156 inode_set_ctime_current(inode);
157 inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir));
158 mark_inode_dirty(inode);
159 mark_inode_dirty(dir);
160 d_instantiate(de, inode);
161 } else {
162 drop_nlink(inode);
163 iput(inode);
164 }
165
166 if (inode != dir)
167 ni_unlock(ni);
168 ni_unlock(ntfs_i(dir));
169
170 return err;
171 }
172
173 /*
174 * ntfs_unlink - inode_operations::unlink
175 */
ntfs_unlink(struct inode * dir,struct dentry * dentry)176 static int ntfs_unlink(struct inode *dir, struct dentry *dentry)
177 {
178 struct ntfs_inode *dir_ni = ntfs_i(dir);
179 struct inode *inode = d_inode(dentry);
180 struct ntfs_inode *ni = ntfs_i(inode);
181 int err;
182
183 /* Avoid any operation if inode is bad. */
184 if (unlikely(is_bad_ni(ni)))
185 return -EINVAL;
186
187 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
188 return -EIO;
189
190 if (likely(is_ni_base(ni))) {
191 ni_lock_dir(dir_ni);
192 /* Remove general file/dir. */
193 err = ntfs_unlink_inode(dir, dentry);
194 ni_unlock(dir_ni);
195 } else {
196 ni_lock(ni);
197 /* Remove ADS. */
198 err = ni_remove_attr(ni, ATTR_DATA, ni->file.ads.name,
199 ni->file.ads.len, false, NULL);
200 ni_unlock(ni);
201
202 if (!err)
203 drop_nlink(inode);
204 }
205
206 return err;
207 }
208
209 /*
210 * ntfs_symlink - inode_operations::symlink
211 */
ntfs_symlink(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,const char * symname)212 static int ntfs_symlink(struct mnt_idmap *idmap, struct inode *dir,
213 struct dentry *dentry, const char *symname)
214 {
215 u32 size = strlen(symname);
216
217 /* Avoid any operation if inode is bad. */
218 if (unlikely(is_bad_ni(ntfs_i(dir))))
219 return -EINVAL;
220
221 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
222 return -EIO;
223
224 return ntfs_create_inode(idmap, dir, dentry, NULL, S_IFLNK | 0777, 0,
225 symname, size, NULL);
226 }
227
228 /*
229 * ntfs_mkdir - inode_operations::mkdir
230 */
ntfs_mkdir(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,umode_t mode)231 static struct dentry *ntfs_mkdir(struct mnt_idmap *idmap, struct inode *dir,
232 struct dentry *dentry, umode_t mode)
233 {
234 return ERR_PTR(ntfs_create_inode(idmap, dir, dentry, NULL,
235 mode, 0, NULL, 0, NULL));
236 }
237
238 /*
239 * ntfs_rmdir - inode_operations::rmdir
240 */
ntfs_rmdir(struct inode * dir,struct dentry * dentry)241 static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
242 {
243 struct ntfs_inode *ni = ntfs_i(dir);
244 int err;
245
246 /* Avoid any operation if inode is bad. */
247 if (unlikely(is_bad_ni(ni)))
248 return -EINVAL;
249
250 if (unlikely(ntfs3_forced_shutdown(dir->i_sb)))
251 return -EIO;
252
253 ni_lock_dir(ni);
254
255 err = ntfs_unlink_inode(dir, dentry);
256
257 ni_unlock(ni);
258
259 return err;
260 }
261
262 /*
263 * ntfs_rename - inode_operations::rename
264 */
ntfs_rename(struct mnt_idmap * idmap,struct inode * dir,struct dentry * dentry,struct inode * new_dir,struct dentry * new_dentry,u32 flags)265 static int ntfs_rename(struct mnt_idmap *idmap, struct inode *dir,
266 struct dentry *dentry, struct inode *new_dir,
267 struct dentry *new_dentry, u32 flags)
268 {
269 int err;
270 struct super_block *sb = dir->i_sb;
271 struct ntfs_sb_info *sbi = sb->s_fs_info;
272 struct ntfs_inode *dir_ni = ntfs_i(dir);
273 struct ntfs_inode *new_dir_ni = ntfs_i(new_dir);
274 struct inode *inode = d_inode(dentry);
275 struct ntfs_inode *ni = ntfs_i(inode);
276 struct inode *new_inode = d_inode(new_dentry);
277 struct NTFS_DE *de, *new_de;
278 bool is_same;
279 /*
280 * de - memory of PATH_MAX bytes:
281 * [0-1024) - original name (dentry->d_name)
282 * [1024-2048) - paired to original name, usually DOS variant of dentry->d_name
283 * [2048-3072) - new name (new_dentry->d_name)
284 */
285 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
286 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
287 1024);
288 static_assert(PATH_MAX >= 4 * 1024);
289
290 if (!is_ni_base(ni)) {
291 /* No rename for ADS. */
292 return -EOPNOTSUPP;
293 }
294
295 /* Avoid any operation if inode is bad. */
296 if (unlikely(is_bad_ni(ni)))
297 return -EINVAL;
298
299 if (unlikely(ntfs3_forced_shutdown(sb)))
300 return -EIO;
301
302 if (flags & ~RENAME_NOREPLACE)
303 return -EINVAL;
304
305 is_same = dentry->d_name.len == new_dentry->d_name.len &&
306 !memcmp(dentry->d_name.name, new_dentry->d_name.name,
307 dentry->d_name.len);
308
309 if (is_same && dir == new_dir) {
310 /* Nothing to do. */
311 return 0;
312 }
313
314 if (ntfs_is_meta_file(sbi, inode->i_ino)) {
315 /* Should we print an error? */
316 return -EINVAL;
317 }
318
319 if (new_inode) {
320 /* Target name exists. Unlink it. */
321 dget(new_dentry);
322 ni_lock_dir(new_dir_ni);
323 err = ntfs_unlink_inode(new_dir, new_dentry);
324 ni_unlock(new_dir_ni);
325 dput(new_dentry);
326 if (err)
327 return err;
328 }
329
330 de = kmalloc(PATH_MAX, GFP_KERNEL);
331 if (!de)
332 return -ENOMEM;
333
334 /* Translate dentry->d_name into unicode form. */
335 err = fill_name_de(sbi, de, &dentry->d_name, NULL);
336 if (err < 0)
337 goto out;
338
339 if (is_same) {
340 /* Reuse 'de'. */
341 new_de = de;
342 } else {
343 /* Translate new_dentry->d_name into unicode form. */
344 new_de = Add2Ptr(de, 2048);
345 err = fill_name_de(sbi, new_de, &new_dentry->d_name, NULL);
346 if (err < 0)
347 goto out;
348 }
349
350 ni_lock_dir(dir_ni);
351 ni_lock(ni);
352 if (dir_ni != new_dir_ni)
353 ni_lock_dir2(new_dir_ni);
354
355 err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de);
356 if (!err) {
357 simple_rename_timestamp(dir, dentry, new_dir, new_dentry);
358 mark_inode_dirty(inode);
359 mark_inode_dirty(dir);
360 if (dir != new_dir)
361 mark_inode_dirty(new_dir);
362
363 if (IS_DIRSYNC(dir))
364 ntfs_sync_inode(dir);
365
366 if (IS_DIRSYNC(new_dir))
367 ntfs_sync_inode(new_dir);
368 }
369
370 if (dir_ni != new_dir_ni)
371 ni_unlock(new_dir_ni);
372 ni_unlock(ni);
373 ni_unlock(dir_ni);
374 out:
375 kfree(de);
376 return err;
377 }
378
ntfs3_get_parent(struct dentry * child)379 struct dentry *ntfs3_get_parent(struct dentry *child)
380 {
381 struct inode *inode = d_inode(child);
382 struct ntfs_inode *ni = ntfs_i(inode);
383
384 struct ATTR_LIST_ENTRY *le = NULL;
385 struct ATTRIB *attr = NULL;
386 struct ATTR_FILE_NAME *fname;
387
388 while ((attr = ni_find_attr(ni, attr, &le, ATTR_NAME, NULL, 0, NULL,
389 NULL))) {
390 fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
391 if (!fname)
392 continue;
393
394 return d_obtain_alias(
395 ntfs_iget5(inode->i_sb, &fname->home, NULL));
396 }
397
398 return ERR_PTR(-ENOENT);
399 }
400
401 /*
402 * dentry_operations::d_hash
403 */
ntfs_d_hash(const struct dentry * dentry,struct qstr * name)404 static int ntfs_d_hash(const struct dentry *dentry, struct qstr *name)
405 {
406 struct ntfs_sb_info *sbi;
407 const char *n = name->name;
408 unsigned int len = name->len;
409 unsigned long hash;
410 struct cpu_str *uni;
411 unsigned int c;
412 int err;
413
414 /* First try fast implementation. */
415 hash = init_name_hash(dentry);
416
417 for (;;) {
418 if (!len--) {
419 name->hash = end_name_hash(hash);
420 return 0;
421 }
422
423 c = *n++;
424 if (c >= 0x80)
425 break;
426
427 hash = partial_name_hash(toupper(c), hash);
428 }
429
430 /*
431 * Try slow way with current upcase table
432 */
433 uni = kmalloc(PATH_MAX, GFP_NOWAIT);
434 if (!uni)
435 return -ENOMEM;
436
437 sbi = dentry->d_sb->s_fs_info;
438
439 err = ntfs_nls_to_utf16(sbi, name->name, name->len, uni, NTFS_NAME_LEN,
440 UTF16_HOST_ENDIAN);
441 if (err < 0)
442 goto out;
443
444 if (!err) {
445 err = -EINVAL;
446 goto out;
447 }
448
449 hash = ntfs_names_hash(uni->name, uni->len, sbi->upcase,
450 init_name_hash(dentry));
451 name->hash = end_name_hash(hash);
452 err = 0;
453
454 out:
455 kfree(uni);
456 return err;
457 }
458
459 /*
460 * dentry_operations::d_compare
461 */
ntfs_d_compare(const struct dentry * dentry,unsigned int len1,const char * str,const struct qstr * name)462 static int ntfs_d_compare(const struct dentry *dentry, unsigned int len1,
463 const char *str, const struct qstr *name)
464 {
465 struct ntfs_sb_info *sbi;
466 int ret;
467 const char *n1 = str;
468 const char *n2 = name->name;
469 unsigned int len2 = name->len;
470 unsigned int lm = min(len1, len2);
471 unsigned char c1, c2;
472 struct cpu_str *uni1;
473 struct le_str *uni2;
474
475 /* First try fast implementation. */
476 for (;;) {
477 if (!lm--)
478 return len1 != len2;
479
480 if ((c1 = *n1++) == (c2 = *n2++))
481 continue;
482
483 if (c1 >= 0x80 || c2 >= 0x80)
484 break;
485
486 if (toupper(c1) != toupper(c2))
487 return 1;
488 }
489
490 /*
491 * Try slow way with current upcase table
492 */
493 sbi = dentry->d_sb->s_fs_info;
494 uni1 = kmalloc(PATH_MAX, GFP_NOWAIT);
495 if (!uni1)
496 return -ENOMEM;
497
498 ret = ntfs_nls_to_utf16(sbi, str, len1, uni1, NTFS_NAME_LEN,
499 UTF16_HOST_ENDIAN);
500 if (ret < 0)
501 goto out;
502
503 if (!ret) {
504 ret = -EINVAL;
505 goto out;
506 }
507
508 uni2 = Add2Ptr(uni1, 2048);
509
510 ret = ntfs_nls_to_utf16(sbi, name->name, name->len,
511 (struct cpu_str *)uni2, NTFS_NAME_LEN,
512 UTF16_LITTLE_ENDIAN);
513 if (ret < 0)
514 goto out;
515
516 if (!ret) {
517 ret = -EINVAL;
518 goto out;
519 }
520
521 ret = !ntfs_cmp_names_cpu(uni1, uni2, sbi->upcase, false) ? 0 : 1;
522
523 out:
524 kfree(uni1);
525 return ret;
526 }
527
528 // clang-format off
529 const struct inode_operations ntfs_dir_inode_operations = {
530 .lookup = ntfs_lookup,
531 .create = ntfs_create,
532 .link = ntfs_link,
533 .unlink = ntfs_unlink,
534 .symlink = ntfs_symlink,
535 .mkdir = ntfs_mkdir,
536 .rmdir = ntfs_rmdir,
537 .mknod = ntfs_mknod,
538 .rename = ntfs_rename,
539 .get_acl = ntfs_get_acl,
540 .set_acl = ntfs_set_acl,
541 .setattr = ntfs_setattr,
542 .getattr = ntfs_getattr,
543 .listxattr = ntfs_listxattr,
544 .fiemap = ntfs_fiemap,
545 .fileattr_get = ntfs_fileattr_get,
546 .fileattr_set = ntfs_fileattr_set,
547 };
548
549 const struct inode_operations ntfs_special_inode_operations = {
550 .setattr = ntfs_setattr,
551 .getattr = ntfs_getattr,
552 .listxattr = ntfs_listxattr,
553 .get_acl = ntfs_get_acl,
554 .set_acl = ntfs_set_acl,
555 .fileattr_get = ntfs_fileattr_get,
556 .fileattr_set = ntfs_fileattr_set,
557 };
558
559 const struct dentry_operations ntfs_dentry_ops = {
560 .d_hash = ntfs_d_hash,
561 .d_compare = ntfs_d_compare,
562 };
563
564 // clang-format on
565