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/posix_acl.h>
10 #include <linux/posix_acl_xattr.h>
11 #include <linux/xattr.h>
12
13 #include "debug.h"
14 #include "ntfs.h"
15 #include "ntfs_fs.h"
16
17 // clang-format off
18 #define SYSTEM_DOS_ATTRIB "system.dos_attrib"
19 #define SYSTEM_NTFS_ATTRIB "system.ntfs_attrib"
20 #define SYSTEM_NTFS_SECURITY "system.ntfs_security"
21 // clang-format on
22
unpacked_ea_size(const struct EA_FULL * ea)23 static inline size_t unpacked_ea_size(const struct EA_FULL *ea)
24 {
25 return ea->size ? le32_to_cpu(ea->size)
26 : ALIGN(struct_size(ea, name,
27 1 + ea->name_len +
28 le16_to_cpu(ea->elength)),
29 4);
30 }
31
packed_ea_size(const struct EA_FULL * ea)32 static inline size_t packed_ea_size(const struct EA_FULL *ea)
33 {
34 return struct_size(ea, name,
35 1 + ea->name_len + le16_to_cpu(ea->elength)) -
36 offsetof(struct EA_FULL, flags);
37 }
38
39 /*
40 * find_ea
41 *
42 * Assume there is at least one xattr in the list.
43 */
find_ea(const struct EA_FULL * ea_all,u32 bytes,const char * name,u8 name_len,u32 * off)44 static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
45 const char *name, u8 name_len, u32 *off)
46 {
47 *off = 0;
48
49 if (!ea_all || !bytes)
50 return false;
51
52 for (;;) {
53 const struct EA_FULL *ea = Add2Ptr(ea_all, *off);
54 u32 next_off = *off + unpacked_ea_size(ea);
55
56 if (next_off > bytes)
57 return false;
58
59 if (ea->name_len == name_len &&
60 !memcmp(ea->name, name, name_len))
61 return true;
62
63 *off = next_off;
64 if (next_off >= bytes)
65 return false;
66 }
67 }
68
69 /*
70 * ntfs_read_ea - Read all extended attributes.
71 * @ea: New allocated memory.
72 * @info: Pointer into resident data.
73 */
ntfs_read_ea(struct ntfs_inode * ni,struct EA_FULL ** ea,size_t add_bytes,const struct EA_INFO ** info)74 static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
75 size_t add_bytes, const struct EA_INFO **info)
76 {
77 int err;
78 struct ntfs_sb_info *sbi = ni->mi.sbi;
79 struct ATTR_LIST_ENTRY *le = NULL;
80 struct ATTRIB *attr_info, *attr_ea;
81 void *ea_p;
82 u32 size;
83
84 static_assert(le32_to_cpu(ATTR_EA_INFO) < le32_to_cpu(ATTR_EA));
85
86 *ea = NULL;
87 *info = NULL;
88
89 attr_info =
90 ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, NULL);
91 attr_ea =
92 ni_find_attr(ni, attr_info, &le, ATTR_EA, NULL, 0, NULL, NULL);
93
94 if (!attr_ea || !attr_info)
95 return 0;
96
97 *info = resident_data_ex(attr_info, sizeof(struct EA_INFO));
98 if (!*info)
99 return -EINVAL;
100
101 /* Check Ea limit. */
102 size = le32_to_cpu((*info)->size);
103 if (size > sbi->ea_max_size)
104 return -EFBIG;
105
106 if (attr_size(attr_ea) > sbi->ea_max_size)
107 return -EFBIG;
108
109 /* Allocate memory for packed Ea. */
110 ea_p = kmalloc(size + add_bytes, GFP_NOFS);
111 if (!ea_p)
112 return -ENOMEM;
113
114 if (!size) {
115 ;
116 } else if (attr_ea->non_res) {
117 struct runs_tree run;
118
119 run_init(&run);
120
121 err = attr_load_runs(attr_ea, ni, &run, NULL);
122 if (!err)
123 err = ntfs_read_run_nb(sbi, &run, 0, ea_p, size, NULL);
124 run_close(&run);
125
126 if (err)
127 goto out;
128 } else {
129 void *p = resident_data_ex(attr_ea, size);
130
131 if (!p) {
132 err = -EINVAL;
133 goto out;
134 }
135 memcpy(ea_p, p, size);
136 }
137
138 memset(Add2Ptr(ea_p, size), 0, add_bytes);
139 *ea = ea_p;
140 return 0;
141
142 out:
143 kfree(ea_p);
144 *ea = NULL;
145 return err;
146 }
147
148 /*
149 * ntfs_list_ea
150 *
151 * Copy a list of xattrs names into the buffer
152 * provided, or compute the buffer size required.
153 *
154 * Return:
155 * * Number of bytes used / required on
156 * * -ERRNO - on failure
157 */
ntfs_list_ea(struct ntfs_inode * ni,char * buffer,size_t bytes_per_buffer)158 static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
159 size_t bytes_per_buffer)
160 {
161 const struct EA_INFO *info;
162 struct EA_FULL *ea_all = NULL;
163 const struct EA_FULL *ea;
164 u32 off, size;
165 int err;
166 size_t ret;
167
168 err = ntfs_read_ea(ni, &ea_all, 0, &info);
169 if (err)
170 return err;
171
172 if (!info || !ea_all)
173 return 0;
174
175 size = le32_to_cpu(info->size);
176
177 /* Enumerate all xattrs. */
178 for (ret = 0, off = 0; off < size; off += unpacked_ea_size(ea)) {
179 ea = Add2Ptr(ea_all, off);
180
181 if (buffer) {
182 if (ret + ea->name_len + 1 > bytes_per_buffer) {
183 err = -ERANGE;
184 goto out;
185 }
186
187 memcpy(buffer + ret, ea->name, ea->name_len);
188 buffer[ret + ea->name_len] = 0;
189 }
190
191 ret += ea->name_len + 1;
192 }
193
194 out:
195 kfree(ea_all);
196 return err ? err : ret;
197 }
198
ntfs_get_ea(struct inode * inode,const char * name,size_t name_len,void * buffer,size_t size,size_t * required)199 static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
200 void *buffer, size_t size, size_t *required)
201 {
202 struct ntfs_inode *ni = ntfs_i(inode);
203 const struct EA_INFO *info;
204 struct EA_FULL *ea_all = NULL;
205 const struct EA_FULL *ea;
206 u32 off, len;
207 int err;
208
209 if (!(ni->ni_flags & NI_FLAG_EA))
210 return -ENODATA;
211
212 if (!required)
213 ni_lock(ni);
214
215 len = 0;
216
217 if (name_len > 255) {
218 err = -ENAMETOOLONG;
219 goto out;
220 }
221
222 err = ntfs_read_ea(ni, &ea_all, 0, &info);
223 if (err)
224 goto out;
225
226 if (!info)
227 goto out;
228
229 /* Enumerate all xattrs. */
230 if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off)) {
231 err = -ENODATA;
232 goto out;
233 }
234 ea = Add2Ptr(ea_all, off);
235
236 len = le16_to_cpu(ea->elength);
237 if (!buffer) {
238 err = 0;
239 goto out;
240 }
241
242 if (len > size) {
243 err = -ERANGE;
244 if (required)
245 *required = len;
246 goto out;
247 }
248
249 memcpy(buffer, ea->name + ea->name_len + 1, len);
250 err = 0;
251
252 out:
253 kfree(ea_all);
254 if (!required)
255 ni_unlock(ni);
256
257 return err ? err : len;
258 }
259
ntfs_set_ea(struct inode * inode,const char * name,size_t name_len,const void * value,size_t val_size,int flags)260 static noinline int ntfs_set_ea(struct inode *inode, const char *name,
261 size_t name_len, const void *value,
262 size_t val_size, int flags)
263 {
264 struct ntfs_inode *ni = ntfs_i(inode);
265 struct ntfs_sb_info *sbi = ni->mi.sbi;
266 int err;
267 struct EA_INFO ea_info;
268 const struct EA_INFO *info;
269 struct EA_FULL *new_ea;
270 struct EA_FULL *ea_all = NULL;
271 size_t add, new_pack;
272 u32 off, size;
273 __le16 size_pack;
274 struct ATTRIB *attr;
275 struct ATTR_LIST_ENTRY *le;
276 struct mft_inode *mi;
277 struct runs_tree ea_run;
278 u64 new_sz;
279 void *p;
280
281 ni_lock(ni);
282
283 run_init(&ea_run);
284
285 if (name_len > 255) {
286 err = -ENAMETOOLONG;
287 goto out;
288 }
289
290 add = ALIGN(struct_size(ea_all, name, 1 + name_len + val_size), 4);
291
292 err = ntfs_read_ea(ni, &ea_all, add, &info);
293 if (err)
294 goto out;
295
296 if (!info) {
297 memset(&ea_info, 0, sizeof(ea_info));
298 size = 0;
299 size_pack = 0;
300 } else {
301 memcpy(&ea_info, info, sizeof(ea_info));
302 size = le32_to_cpu(ea_info.size);
303 size_pack = ea_info.size_pack;
304 }
305
306 if (info && find_ea(ea_all, size, name, name_len, &off)) {
307 struct EA_FULL *ea;
308 size_t ea_sz;
309
310 if (flags & XATTR_CREATE) {
311 err = -EEXIST;
312 goto out;
313 }
314
315 ea = Add2Ptr(ea_all, off);
316
317 /*
318 * Check simple case when we try to insert xattr with the same value
319 * e.g. ntfs_save_wsl_perm
320 */
321 if (val_size && le16_to_cpu(ea->elength) == val_size &&
322 !memcmp(ea->name + ea->name_len + 1, value, val_size)) {
323 /* xattr already contains the required value. */
324 goto out;
325 }
326
327 /* Remove current xattr. */
328 if (ea->flags & FILE_NEED_EA)
329 le16_add_cpu(&ea_info.count, -1);
330
331 ea_sz = unpacked_ea_size(ea);
332
333 le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));
334
335 memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);
336
337 size -= ea_sz;
338 memset(Add2Ptr(ea_all, size), 0, ea_sz);
339
340 ea_info.size = cpu_to_le32(size);
341
342 if ((flags & XATTR_REPLACE) && !val_size) {
343 /* Remove xattr. */
344 goto update_ea;
345 }
346 } else {
347 if (flags & XATTR_REPLACE) {
348 err = -ENODATA;
349 goto out;
350 }
351
352 if (!ea_all) {
353 ea_all = kzalloc(add, GFP_NOFS);
354 if (!ea_all) {
355 err = -ENOMEM;
356 goto out;
357 }
358 }
359 }
360
361 /* Append new xattr. */
362 new_ea = Add2Ptr(ea_all, size);
363 new_ea->size = cpu_to_le32(add);
364 new_ea->flags = 0;
365 new_ea->name_len = name_len;
366 new_ea->elength = cpu_to_le16(val_size);
367 memcpy(new_ea->name, name, name_len);
368 new_ea->name[name_len] = 0;
369 memcpy(new_ea->name + name_len + 1, value, val_size);
370 new_pack = le16_to_cpu(ea_info.size_pack) + packed_ea_size(new_ea);
371 ea_info.size_pack = cpu_to_le16(new_pack);
372 /* New size of ATTR_EA. */
373 size += add;
374 ea_info.size = cpu_to_le32(size);
375
376 /*
377 * 1. Check ea_info.size_pack for overflow.
378 * 2. New attibute size must fit value from $AttrDef
379 */
380 if (new_pack > 0xffff || size > sbi->ea_max_size) {
381 ntfs_inode_warn(
382 inode,
383 "The size of extended attributes must not exceed 64KiB");
384 err = -EFBIG; // -EINVAL?
385 goto out;
386 }
387
388 update_ea:
389
390 if (!info) {
391 /* Create xattr. */
392 if (!size) {
393 err = 0;
394 goto out;
395 }
396
397 err = ni_insert_resident(ni, sizeof(struct EA_INFO),
398 ATTR_EA_INFO, NULL, 0, NULL, NULL,
399 NULL);
400 if (err)
401 goto out;
402
403 err = ni_insert_resident(ni, 0, ATTR_EA, NULL, 0, NULL, NULL,
404 NULL);
405 if (err)
406 goto out;
407 }
408
409 new_sz = size;
410 err = attr_set_size(ni, ATTR_EA, NULL, 0, &ea_run, new_sz, &new_sz,
411 false, NULL);
412 if (err)
413 goto out;
414
415 le = NULL;
416 attr = ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, &mi);
417 if (!attr) {
418 err = -EINVAL;
419 goto out;
420 }
421
422 if (!size) {
423 /* Delete xattr, ATTR_EA_INFO */
424 ni_remove_attr_le(ni, attr, mi, le);
425 } else {
426 p = resident_data_ex(attr, sizeof(struct EA_INFO));
427 if (!p) {
428 err = -EINVAL;
429 goto out;
430 }
431 memcpy(p, &ea_info, sizeof(struct EA_INFO));
432 mi->dirty = true;
433 }
434
435 le = NULL;
436 attr = ni_find_attr(ni, NULL, &le, ATTR_EA, NULL, 0, NULL, &mi);
437 if (!attr) {
438 err = -EINVAL;
439 goto out;
440 }
441
442 if (!size) {
443 /* Delete xattr, ATTR_EA */
444 ni_remove_attr_le(ni, attr, mi, le);
445 } else if (attr->non_res) {
446 err = ntfs_sb_write_run(sbi, &ea_run, 0, ea_all, size, 0);
447 if (err)
448 goto out;
449 } else {
450 p = resident_data_ex(attr, size);
451 if (!p) {
452 err = -EINVAL;
453 goto out;
454 }
455 memcpy(p, ea_all, size);
456 mi->dirty = true;
457 }
458
459 /* Check if we delete the last xattr. */
460 if (size)
461 ni->ni_flags |= NI_FLAG_EA;
462 else
463 ni->ni_flags &= ~NI_FLAG_EA;
464
465 if (ea_info.size_pack != size_pack)
466 ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
467 mark_inode_dirty(&ni->vfs_inode);
468
469 out:
470 ni_unlock(ni);
471
472 run_close(&ea_run);
473 kfree(ea_all);
474
475 return err;
476 }
477
478 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
ntfs_get_acl_ex(struct user_namespace * mnt_userns,struct inode * inode,int type,int locked)479 static struct posix_acl *ntfs_get_acl_ex(struct user_namespace *mnt_userns,
480 struct inode *inode, int type,
481 int locked)
482 {
483 struct ntfs_inode *ni = ntfs_i(inode);
484 const char *name;
485 size_t name_len;
486 struct posix_acl *acl;
487 size_t req;
488 int err;
489 void *buf;
490
491 /* Allocate PATH_MAX bytes. */
492 buf = __getname();
493 if (!buf)
494 return ERR_PTR(-ENOMEM);
495
496 /* Possible values of 'type' was already checked above. */
497 if (type == ACL_TYPE_ACCESS) {
498 name = XATTR_NAME_POSIX_ACL_ACCESS;
499 name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
500 } else {
501 name = XATTR_NAME_POSIX_ACL_DEFAULT;
502 name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
503 }
504
505 if (!locked)
506 ni_lock(ni);
507
508 err = ntfs_get_ea(inode, name, name_len, buf, PATH_MAX, &req);
509
510 if (!locked)
511 ni_unlock(ni);
512
513 /* Translate extended attribute to acl. */
514 if (err >= 0) {
515 acl = posix_acl_from_xattr(mnt_userns, buf, err);
516 } else if (err == -ENODATA) {
517 acl = NULL;
518 } else {
519 acl = ERR_PTR(err);
520 }
521
522 if (!IS_ERR(acl))
523 set_cached_acl(inode, type, acl);
524
525 __putname(buf);
526
527 return acl;
528 }
529
530 /*
531 * ntfs_get_acl - inode_operations::get_acl
532 */
ntfs_get_acl(struct inode * inode,int type,bool rcu)533 struct posix_acl *ntfs_get_acl(struct inode *inode, int type, bool rcu)
534 {
535 if (rcu)
536 return ERR_PTR(-ECHILD);
537
538 /* TODO: init_user_ns? */
539 return ntfs_get_acl_ex(&init_user_ns, inode, type, 0);
540 }
541
ntfs_set_acl_ex(struct user_namespace * mnt_userns,struct inode * inode,struct posix_acl * acl,int type)542 static noinline int ntfs_set_acl_ex(struct user_namespace *mnt_userns,
543 struct inode *inode, struct posix_acl *acl,
544 int type)
545 {
546 const char *name;
547 size_t size, name_len;
548 void *value = NULL;
549 int err = 0;
550 int flags;
551
552 if (S_ISLNK(inode->i_mode))
553 return -EOPNOTSUPP;
554
555 switch (type) {
556 case ACL_TYPE_ACCESS:
557 if (acl) {
558 umode_t mode = inode->i_mode;
559
560 err = posix_acl_update_mode(mnt_userns, inode, &mode,
561 &acl);
562 if (err)
563 goto out;
564
565 if (inode->i_mode != mode) {
566 inode->i_mode = mode;
567 mark_inode_dirty(inode);
568 }
569 }
570 name = XATTR_NAME_POSIX_ACL_ACCESS;
571 name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
572 break;
573
574 case ACL_TYPE_DEFAULT:
575 if (!S_ISDIR(inode->i_mode))
576 return acl ? -EACCES : 0;
577 name = XATTR_NAME_POSIX_ACL_DEFAULT;
578 name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
579 break;
580
581 default:
582 return -EINVAL;
583 }
584
585 if (!acl) {
586 /* Remove xattr if it can be presented via mode. */
587 size = 0;
588 value = NULL;
589 flags = XATTR_REPLACE;
590 } else {
591 size = posix_acl_xattr_size(acl->a_count);
592 value = kmalloc(size, GFP_NOFS);
593 if (!value)
594 return -ENOMEM;
595 err = posix_acl_to_xattr(mnt_userns, acl, value, size);
596 if (err < 0)
597 goto out;
598 flags = 0;
599 }
600
601 err = ntfs_set_ea(inode, name, name_len, value, size, flags);
602 if (err == -ENODATA && !size)
603 err = 0; /* Removing non existed xattr. */
604 if (!err)
605 set_cached_acl(inode, type, acl);
606
607 out:
608 kfree(value);
609
610 return err;
611 }
612
613 /*
614 * ntfs_set_acl - inode_operations::set_acl
615 */
ntfs_set_acl(struct user_namespace * mnt_userns,struct inode * inode,struct posix_acl * acl,int type)616 int ntfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
617 struct posix_acl *acl, int type)
618 {
619 return ntfs_set_acl_ex(mnt_userns, inode, acl, type);
620 }
621
622 /*
623 * ntfs_init_acl - Initialize the ACLs of a new inode.
624 *
625 * Called from ntfs_create_inode().
626 */
ntfs_init_acl(struct user_namespace * mnt_userns,struct inode * inode,struct inode * dir)627 int ntfs_init_acl(struct user_namespace *mnt_userns, struct inode *inode,
628 struct inode *dir)
629 {
630 struct posix_acl *default_acl, *acl;
631 int err;
632
633 err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
634 if (err)
635 return err;
636
637 if (default_acl) {
638 err = ntfs_set_acl_ex(mnt_userns, inode, default_acl,
639 ACL_TYPE_DEFAULT);
640 posix_acl_release(default_acl);
641 } else {
642 inode->i_default_acl = NULL;
643 }
644
645 if (!acl)
646 inode->i_acl = NULL;
647 else {
648 if (!err)
649 err = ntfs_set_acl_ex(mnt_userns, inode, acl,
650 ACL_TYPE_ACCESS);
651 posix_acl_release(acl);
652 }
653
654 return err;
655 }
656 #endif
657
658 /*
659 * ntfs_acl_chmod - Helper for ntfs3_setattr().
660 */
ntfs_acl_chmod(struct user_namespace * mnt_userns,struct inode * inode)661 int ntfs_acl_chmod(struct user_namespace *mnt_userns, struct inode *inode)
662 {
663 struct super_block *sb = inode->i_sb;
664
665 if (!(sb->s_flags & SB_POSIXACL))
666 return 0;
667
668 if (S_ISLNK(inode->i_mode))
669 return -EOPNOTSUPP;
670
671 return posix_acl_chmod(mnt_userns, inode, inode->i_mode);
672 }
673
674 /*
675 * ntfs_permission - inode_operations::permission
676 */
ntfs_permission(struct user_namespace * mnt_userns,struct inode * inode,int mask)677 int ntfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
678 int mask)
679 {
680 if (ntfs_sb(inode->i_sb)->options->noacsrules) {
681 /* "No access rules" mode - Allow all changes. */
682 return 0;
683 }
684
685 return generic_permission(mnt_userns, inode, mask);
686 }
687
688 /*
689 * ntfs_listxattr - inode_operations::listxattr
690 */
ntfs_listxattr(struct dentry * dentry,char * buffer,size_t size)691 ssize_t ntfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
692 {
693 struct inode *inode = d_inode(dentry);
694 struct ntfs_inode *ni = ntfs_i(inode);
695 ssize_t ret;
696
697 if (!(ni->ni_flags & NI_FLAG_EA)) {
698 /* no xattr in file */
699 return 0;
700 }
701
702 ni_lock(ni);
703
704 ret = ntfs_list_ea(ni, buffer, size);
705
706 ni_unlock(ni);
707
708 return ret;
709 }
710
ntfs_getxattr(const struct xattr_handler * handler,struct dentry * de,struct inode * inode,const char * name,void * buffer,size_t size)711 static int ntfs_getxattr(const struct xattr_handler *handler, struct dentry *de,
712 struct inode *inode, const char *name, void *buffer,
713 size_t size)
714 {
715 int err;
716 struct ntfs_inode *ni = ntfs_i(inode);
717 size_t name_len = strlen(name);
718
719 /* Dispatch request. */
720 if (name_len == sizeof(SYSTEM_DOS_ATTRIB) - 1 &&
721 !memcmp(name, SYSTEM_DOS_ATTRIB, sizeof(SYSTEM_DOS_ATTRIB))) {
722 /* system.dos_attrib */
723 if (!buffer) {
724 err = sizeof(u8);
725 } else if (size < sizeof(u8)) {
726 err = -ENODATA;
727 } else {
728 err = sizeof(u8);
729 *(u8 *)buffer = le32_to_cpu(ni->std_fa);
730 }
731 goto out;
732 }
733
734 if (name_len == sizeof(SYSTEM_NTFS_ATTRIB) - 1 &&
735 !memcmp(name, SYSTEM_NTFS_ATTRIB, sizeof(SYSTEM_NTFS_ATTRIB))) {
736 /* system.ntfs_attrib */
737 if (!buffer) {
738 err = sizeof(u32);
739 } else if (size < sizeof(u32)) {
740 err = -ENODATA;
741 } else {
742 err = sizeof(u32);
743 *(u32 *)buffer = le32_to_cpu(ni->std_fa);
744 }
745 goto out;
746 }
747
748 if (name_len == sizeof(SYSTEM_NTFS_SECURITY) - 1 &&
749 !memcmp(name, SYSTEM_NTFS_SECURITY, sizeof(SYSTEM_NTFS_SECURITY))) {
750 /* system.ntfs_security*/
751 struct SECURITY_DESCRIPTOR_RELATIVE *sd = NULL;
752 size_t sd_size = 0;
753
754 if (!is_ntfs3(ni->mi.sbi)) {
755 /* We should get nt4 security. */
756 err = -EINVAL;
757 goto out;
758 } else if (le32_to_cpu(ni->std_security_id) <
759 SECURITY_ID_FIRST) {
760 err = -ENOENT;
761 goto out;
762 }
763
764 err = ntfs_get_security_by_id(ni->mi.sbi, ni->std_security_id,
765 &sd, &sd_size);
766 if (err)
767 goto out;
768
769 if (!is_sd_valid(sd, sd_size)) {
770 ntfs_inode_warn(
771 inode,
772 "looks like you get incorrect security descriptor id=%u",
773 ni->std_security_id);
774 }
775
776 if (!buffer) {
777 err = sd_size;
778 } else if (size < sd_size) {
779 err = -ENODATA;
780 } else {
781 err = sd_size;
782 memcpy(buffer, sd, sd_size);
783 }
784 kfree(sd);
785 goto out;
786 }
787
788 /* Deal with NTFS extended attribute. */
789 err = ntfs_get_ea(inode, name, name_len, buffer, size, NULL);
790
791 out:
792 return err;
793 }
794
795 /*
796 * ntfs_setxattr - inode_operations::setxattr
797 */
ntfs_setxattr(const struct xattr_handler * handler,struct user_namespace * mnt_userns,struct dentry * de,struct inode * inode,const char * name,const void * value,size_t size,int flags)798 static noinline int ntfs_setxattr(const struct xattr_handler *handler,
799 struct user_namespace *mnt_userns,
800 struct dentry *de, struct inode *inode,
801 const char *name, const void *value,
802 size_t size, int flags)
803 {
804 int err = -EINVAL;
805 struct ntfs_inode *ni = ntfs_i(inode);
806 size_t name_len = strlen(name);
807 enum FILE_ATTRIBUTE new_fa;
808
809 /* Dispatch request. */
810 if (name_len == sizeof(SYSTEM_DOS_ATTRIB) - 1 &&
811 !memcmp(name, SYSTEM_DOS_ATTRIB, sizeof(SYSTEM_DOS_ATTRIB))) {
812 if (sizeof(u8) != size)
813 goto out;
814 new_fa = cpu_to_le32(*(u8 *)value);
815 goto set_new_fa;
816 }
817
818 if (name_len == sizeof(SYSTEM_NTFS_ATTRIB) - 1 &&
819 !memcmp(name, SYSTEM_NTFS_ATTRIB, sizeof(SYSTEM_NTFS_ATTRIB))) {
820 if (size != sizeof(u32))
821 goto out;
822 new_fa = cpu_to_le32(*(u32 *)value);
823
824 if (S_ISREG(inode->i_mode)) {
825 /* Process compressed/sparsed in special way. */
826 ni_lock(ni);
827 err = ni_new_attr_flags(ni, new_fa);
828 ni_unlock(ni);
829 if (err)
830 goto out;
831 }
832 set_new_fa:
833 /*
834 * Thanks Mark Harmstone:
835 * Keep directory bit consistency.
836 */
837 if (S_ISDIR(inode->i_mode))
838 new_fa |= FILE_ATTRIBUTE_DIRECTORY;
839 else
840 new_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
841
842 if (ni->std_fa != new_fa) {
843 ni->std_fa = new_fa;
844 if (new_fa & FILE_ATTRIBUTE_READONLY)
845 inode->i_mode &= ~0222;
846 else
847 inode->i_mode |= 0222;
848 /* Std attribute always in primary record. */
849 ni->mi.dirty = true;
850 mark_inode_dirty(inode);
851 }
852 err = 0;
853
854 goto out;
855 }
856
857 if (name_len == sizeof(SYSTEM_NTFS_SECURITY) - 1 &&
858 !memcmp(name, SYSTEM_NTFS_SECURITY, sizeof(SYSTEM_NTFS_SECURITY))) {
859 /* system.ntfs_security*/
860 __le32 security_id;
861 bool inserted;
862 struct ATTR_STD_INFO5 *std;
863
864 if (!is_ntfs3(ni->mi.sbi)) {
865 /*
866 * We should replace ATTR_SECURE.
867 * Skip this way cause it is nt4 feature.
868 */
869 err = -EINVAL;
870 goto out;
871 }
872
873 if (!is_sd_valid(value, size)) {
874 err = -EINVAL;
875 ntfs_inode_warn(
876 inode,
877 "you try to set invalid security descriptor");
878 goto out;
879 }
880
881 err = ntfs_insert_security(ni->mi.sbi, value, size,
882 &security_id, &inserted);
883 if (err)
884 goto out;
885
886 ni_lock(ni);
887 std = ni_std5(ni);
888 if (!std) {
889 err = -EINVAL;
890 } else if (std->security_id != security_id) {
891 std->security_id = ni->std_security_id = security_id;
892 /* Std attribute always in primary record. */
893 ni->mi.dirty = true;
894 mark_inode_dirty(&ni->vfs_inode);
895 }
896 ni_unlock(ni);
897 goto out;
898 }
899
900 /* Deal with NTFS extended attribute. */
901 err = ntfs_set_ea(inode, name, name_len, value, size, flags);
902
903 out:
904 return err;
905 }
906
907 /*
908 * ntfs_save_wsl_perm
909 *
910 * save uid/gid/mode in xattr
911 */
ntfs_save_wsl_perm(struct inode * inode)912 int ntfs_save_wsl_perm(struct inode *inode)
913 {
914 int err;
915 __le32 value;
916
917 /* TODO: refactor this, so we don't lock 4 times in ntfs_set_ea */
918 value = cpu_to_le32(i_uid_read(inode));
919 err = ntfs_set_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value,
920 sizeof(value), 0);
921 if (err)
922 goto out;
923
924 value = cpu_to_le32(i_gid_read(inode));
925 err = ntfs_set_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value,
926 sizeof(value), 0);
927 if (err)
928 goto out;
929
930 value = cpu_to_le32(inode->i_mode);
931 err = ntfs_set_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value,
932 sizeof(value), 0);
933 if (err)
934 goto out;
935
936 if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
937 value = cpu_to_le32(inode->i_rdev);
938 err = ntfs_set_ea(inode, "$LXDEV", sizeof("$LXDEV") - 1, &value,
939 sizeof(value), 0);
940 if (err)
941 goto out;
942 }
943
944 out:
945 /* In case of error should we delete all WSL xattr? */
946 return err;
947 }
948
949 /*
950 * ntfs_get_wsl_perm
951 *
952 * get uid/gid/mode from xattr
953 * it is called from ntfs_iget5->ntfs_read_mft
954 */
ntfs_get_wsl_perm(struct inode * inode)955 void ntfs_get_wsl_perm(struct inode *inode)
956 {
957 size_t sz;
958 __le32 value[3];
959
960 if (ntfs_get_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value[0],
961 sizeof(value[0]), &sz) == sizeof(value[0]) &&
962 ntfs_get_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value[1],
963 sizeof(value[1]), &sz) == sizeof(value[1]) &&
964 ntfs_get_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value[2],
965 sizeof(value[2]), &sz) == sizeof(value[2])) {
966 i_uid_write(inode, (uid_t)le32_to_cpu(value[0]));
967 i_gid_write(inode, (gid_t)le32_to_cpu(value[1]));
968 inode->i_mode = le32_to_cpu(value[2]);
969
970 if (ntfs_get_ea(inode, "$LXDEV", sizeof("$$LXDEV") - 1,
971 &value[0], sizeof(value),
972 &sz) == sizeof(value[0])) {
973 inode->i_rdev = le32_to_cpu(value[0]);
974 }
975 }
976 }
977
ntfs_xattr_user_list(struct dentry * dentry)978 static bool ntfs_xattr_user_list(struct dentry *dentry)
979 {
980 return true;
981 }
982
983 // clang-format off
984 static const struct xattr_handler ntfs_xattr_handler = {
985 .prefix = "",
986 .get = ntfs_getxattr,
987 .set = ntfs_setxattr,
988 .list = ntfs_xattr_user_list,
989 };
990
991 const struct xattr_handler *ntfs_xattr_handlers[] = {
992 &ntfs_xattr_handler,
993 NULL,
994 };
995 // clang-format on
996
