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