summaryrefslogtreecommitdiff
path: root/fs/ntfs3/xattr.c
blob: afd0ddad826ff49f661ce758bcbecec46921fd1c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
// SPDX-License-Identifier: GPL-2.0
/*
 *
 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
 *
 */

#include <linux/fs.h>
#include <linux/posix_acl.h>
#include <linux/posix_acl_xattr.h>
#include <linux/xattr.h>

#include "debug.h"
#include "ntfs.h"
#include "ntfs_fs.h"

// clang-format off
#define SYSTEM_DOS_ATTRIB    "system.dos_attrib"
#define SYSTEM_NTFS_ATTRIB   "system.ntfs_attrib"
#define SYSTEM_NTFS_SECURITY "system.ntfs_security"
// clang-format on

static inline size_t unpacked_ea_size(const struct EA_FULL *ea)
{
	return ea->size ? le32_to_cpu(ea->size)
			: ALIGN(struct_size(ea, name,
					    1 + ea->name_len +
						    le16_to_cpu(ea->elength)),
				4);
}

static inline size_t packed_ea_size(const struct EA_FULL *ea)
{
	return struct_size(ea, name,
			   1 + ea->name_len + le16_to_cpu(ea->elength)) -
	       offsetof(struct EA_FULL, flags);
}

/*
 * find_ea
 *
 * Assume there is at least one xattr in the list.
 */
static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
			   const char *name, u8 name_len, u32 *off)
{
	*off = 0;

	if (!ea_all || !bytes)
		return false;

	for (;;) {
		const struct EA_FULL *ea = Add2Ptr(ea_all, *off);
		u32 next_off = *off + unpacked_ea_size(ea);

		if (next_off > bytes)
			return false;

		if (ea->name_len == name_len &&
		    !memcmp(ea->name, name, name_len))
			return true;

		*off = next_off;
		if (next_off >= bytes)
			return false;
	}
}

/*
 * ntfs_read_ea - Read all extended attributes.
 * @ea:		New allocated memory.
 * @info:	Pointer into resident data.
 */
static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
			size_t add_bytes, const struct EA_INFO **info)
{
	int err;
	struct ntfs_sb_info *sbi = ni->mi.sbi;
	struct ATTR_LIST_ENTRY *le = NULL;
	struct ATTRIB *attr_info, *attr_ea;
	void *ea_p;
	u32 size;

	static_assert(le32_to_cpu(ATTR_EA_INFO) < le32_to_cpu(ATTR_EA));

	*ea = NULL;
	*info = NULL;

	attr_info =
		ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, NULL);
	attr_ea =
		ni_find_attr(ni, attr_info, &le, ATTR_EA, NULL, 0, NULL, NULL);

	if (!attr_ea || !attr_info)
		return 0;

	*info = resident_data_ex(attr_info, sizeof(struct EA_INFO));
	if (!*info)
		return -EINVAL;

	/* Check Ea limit. */
	size = le32_to_cpu((*info)->size);
	if (size > sbi->ea_max_size)
		return -EFBIG;

	if (attr_size(attr_ea) > sbi->ea_max_size)
		return -EFBIG;

	/* Allocate memory for packed Ea. */
	ea_p = kmalloc(size + add_bytes, GFP_NOFS);
	if (!ea_p)
		return -ENOMEM;

	if (!size) {
		;
	} else if (attr_ea->non_res) {
		struct runs_tree run;

		run_init(&run);

		err = attr_load_runs(attr_ea, ni, &run, NULL);
		if (!err)
			err = ntfs_read_run_nb(sbi, &run, 0, ea_p, size, NULL);
		run_close(&run);

		if (err)
			goto out;
	} else {
		void *p = resident_data_ex(attr_ea, size);

		if (!p) {
			err = -EINVAL;
			goto out;
		}
		memcpy(ea_p, p, size);
	}

	memset(Add2Ptr(ea_p, size), 0, add_bytes);
	*ea = ea_p;
	return 0;

out:
	kfree(ea_p);
	*ea = NULL;
	return err;
}

/*
 * ntfs_list_ea
 *
 * Copy a list of xattrs names into the buffer
 * provided, or compute the buffer size required.
 *
 * Return:
 * * Number of bytes used / required on
 * * -ERRNO - on failure
 */
static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
			    size_t bytes_per_buffer)
{
	const struct EA_INFO *info;
	struct EA_FULL *ea_all = NULL;
	const struct EA_FULL *ea;
	u32 off, size;
	int err;
	size_t ret;

	err = ntfs_read_ea(ni, &ea_all, 0, &info);
	if (err)
		return err;

	if (!info || !ea_all)
		return 0;

	size = le32_to_cpu(info->size);

	/* Enumerate all xattrs. */
	for (ret = 0, off = 0; off < size; off += unpacked_ea_size(ea)) {
		ea = Add2Ptr(ea_all, off);

		if (buffer) {
			if (ret + ea->name_len + 1 > bytes_per_buffer) {
				err = -ERANGE;
				goto out;
			}

			memcpy(buffer + ret, ea->name, ea->name_len);
			buffer[ret + ea->name_len] = 0;
		}

		ret += ea->name_len + 1;
	}

out:
	kfree(ea_all);
	return err ? err : ret;
}

static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
		       void *buffer, size_t size, size_t *required)
{
	struct ntfs_inode *ni = ntfs_i(inode);
	const struct EA_INFO *info;
	struct EA_FULL *ea_all = NULL;
	const struct EA_FULL *ea;
	u32 off, len;
	int err;

	if (!(ni->ni_flags & NI_FLAG_EA))
		return -ENODATA;

	if (!required)
		ni_lock(ni);

	len = 0;

	if (name_len > 255) {
		err = -ENAMETOOLONG;
		goto out;
	}

	err = ntfs_read_ea(ni, &ea_all, 0, &info);
	if (err)
		goto out;

	if (!info)
		goto out;

	/* Enumerate all xattrs. */
	if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off)) {
		err = -ENODATA;
		goto out;
	}
	ea = Add2Ptr(ea_all, off);

	len = le16_to_cpu(ea->elength);
	if (!buffer) {
		err = 0;
		goto out;
	}

	if (len > size) {
		err = -ERANGE;
		if (required)
			*required = len;
		goto out;
	}

	memcpy(buffer, ea->name + ea->name_len + 1, len);
	err = 0;

out:
	kfree(ea_all);
	if (!required)
		ni_unlock(ni);

	return err ? err : len;
}

static noinline int ntfs_set_ea(struct inode *inode, const char *name,
				size_t name_len, const void *value,
				size_t val_size, int flags)
{
	struct ntfs_inode *ni = ntfs_i(inode);
	struct ntfs_sb_info *sbi = ni->mi.sbi;
	int err;
	struct EA_INFO ea_info;
	const struct EA_INFO *info;
	struct EA_FULL *new_ea;
	struct EA_FULL *ea_all = NULL;
	size_t add, new_pack;
	u32 off, size;
	__le16 size_pack;
	struct ATTRIB *attr;
	struct ATTR_LIST_ENTRY *le;
	struct mft_inode *mi;
	struct runs_tree ea_run;
	u64 new_sz;
	void *p;

	ni_lock(ni);

	run_init(&ea_run);

	if (name_len > 255) {
		err = -ENAMETOOLONG;
		goto out;
	}

	add = ALIGN(struct_size(ea_all, name, 1 + name_len + val_size), 4);

	err = ntfs_read_ea(ni, &ea_all, add, &info);
	if (err)
		goto out;

	if (!info) {
		memset(&ea_info, 0, sizeof(ea_info));
		size = 0;
		size_pack = 0;
	} else {
		memcpy(&ea_info, info, sizeof(ea_info));
		size = le32_to_cpu(ea_info.size);
		size_pack = ea_info.size_pack;
	}

	if (info && find_ea(ea_all, size, name, name_len, &off)) {
		struct EA_FULL *ea;
		size_t ea_sz;

		if (flags & XATTR_CREATE) {
			err = -EEXIST;
			goto out;
		}

		ea = Add2Ptr(ea_all, off);

		/*
		 * Check simple case when we try to insert xattr with the same value
		 * e.g. ntfs_save_wsl_perm
		 */
		if (val_size && le16_to_cpu(ea->elength) == val_size &&
		    !memcmp(ea->name + ea->name_len + 1, value, val_size)) {
			/* xattr already contains the required value. */
			goto out;
		}

		/* Remove current xattr. */
		if (ea->flags & FILE_NEED_EA)
			le16_add_cpu(&ea_info.count, -1);

		ea_sz = unpacked_ea_size(ea);

		le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));

		memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);

		size -= ea_sz;
		memset(Add2Ptr(ea_all, size), 0, ea_sz);

		ea_info.size = cpu_to_le32(size);

		if ((flags & XATTR_REPLACE) && !val_size) {
			/* Remove xattr. */
			goto update_ea;
		}
	} else {
		if (flags & XATTR_REPLACE) {
			err = -ENODATA;
			goto out;
		}

		if (!ea_all) {
			ea_all = kzalloc(add, GFP_NOFS);
			if (!ea_all) {
				err = -ENOMEM;
				goto out;
			}
		}
	}

	/* Append new xattr. */
	new_ea = Add2Ptr(ea_all, size);
	new_ea->size = cpu_to_le32(add);
	new_ea->flags = 0;
	new_ea->name_len = name_len;
	new_ea->elength = cpu_to_le16(val_size);
	memcpy(new_ea->name, name, name_len);
	new_ea->name[name_len] = 0;
	memcpy(new_ea->name + name_len + 1, value, val_size);
	new_pack = le16_to_cpu(ea_info.size_pack) + packed_ea_size(new_ea);
	ea_info.size_pack = cpu_to_le16(new_pack);
	/* New size of ATTR_EA. */
	size += add;
	ea_info.size = cpu_to_le32(size);

	/*
	 * 1. Check ea_info.size_pack for overflow.
	 * 2. New attibute size must fit value from $AttrDef
	 */
	if (new_pack > 0xffff || size > sbi->ea_max_size) {
		ntfs_inode_warn(
			inode,
			"The size of extended attributes must not exceed 64KiB");
		err = -EFBIG; // -EINVAL?
		goto out;
	}

update_ea:

	if (!info) {
		/* Create xattr. */
		if (!size) {
			err = 0;
			goto out;
		}

		err = ni_insert_resident(ni, sizeof(struct EA_INFO),
					 ATTR_EA_INFO, NULL, 0, NULL, NULL,
					 NULL);
		if (err)
			goto out;

		err = ni_insert_resident(ni, 0, ATTR_EA, NULL, 0, NULL, NULL,
					 NULL);
		if (err)
			goto out;
	}

	new_sz = size;
	err = attr_set_size(ni, ATTR_EA, NULL, 0, &ea_run, new_sz, &new_sz,
			    false, NULL);
	if (err)
		goto out;

	le = NULL;
	attr = ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, &mi);
	if (!attr) {
		err = -EINVAL;
		goto out;
	}

	if (!size) {
		/* Delete xattr, ATTR_EA_INFO */
		ni_remove_attr_le(ni, attr, mi, le);
	} else {
		p = resident_data_ex(attr, sizeof(struct EA_INFO));
		if (!p) {
			err = -EINVAL;
			goto out;
		}
		memcpy(p, &ea_info, sizeof(struct EA_INFO));
		mi->dirty = true;
	}

	le = NULL;
	attr = ni_find_attr(ni, NULL, &le, ATTR_EA, NULL, 0, NULL, &mi);
	if (!attr) {
		err = -EINVAL;
		goto out;
	}

	if (!size) {
		/* Delete xattr, ATTR_EA */
		ni_remove_attr_le(ni, attr, mi, le);
	} else if (attr->non_res) {
		err = ntfs_sb_write_run(sbi, &ea_run, 0, ea_all, size, 0);
		if (err)
			goto out;
	} else {
		p = resident_data_ex(attr, size);
		if (!p) {
			err = -EINVAL;
			goto out;
		}
		memcpy(p, ea_all, size);
		mi->dirty = true;
	}

	/* Check if we delete the last xattr. */
	if (size)
		ni->ni_flags |= NI_FLAG_EA;
	else
		ni->ni_flags &= ~NI_FLAG_EA;

	if (ea_info.size_pack != size_pack)
		ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
	mark_inode_dirty(&ni->vfs_inode);

out:
	ni_unlock(ni);

	run_close(&ea_run);
	kfree(ea_all);

	return err;
}

#ifdef CONFIG_NTFS3_FS_POSIX_ACL
static struct posix_acl *ntfs_get_acl_ex(struct user_namespace *mnt_userns,
					 struct inode *inode, int type,
					 int locked)
{
	struct ntfs_inode *ni = ntfs_i(inode);
	const char *name;
	size_t name_len;
	struct posix_acl *acl;
	size_t req;
	int err;
	void *buf;

	/* Allocate PATH_MAX bytes. */
	buf = __getname();
	if (!buf)
		return ERR_PTR(-ENOMEM);

	/* Possible values of 'type' was already checked above. */
	if (type == ACL_TYPE_ACCESS) {
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
	} else {
		name = XATTR_NAME_POSIX_ACL_DEFAULT;
		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
	}

	if (!locked)
		ni_lock(ni);

	err = ntfs_get_ea(inode, name, name_len, buf, PATH_MAX, &req);

	if (!locked)
		ni_unlock(ni);

	/* Translate extended attribute to acl. */
	if (err >= 0) {
		acl = posix_acl_from_xattr(mnt_userns, buf, err);
	} else if (err == -ENODATA) {
		acl = NULL;
	} else {
		acl = ERR_PTR(err);
	}

	if (!IS_ERR(acl))
		set_cached_acl(inode, type, acl);

	__putname(buf);

	return acl;
}

/*
 * ntfs_get_acl - inode_operations::get_acl
 */
struct posix_acl *ntfs_get_acl(struct inode *inode, int type, bool rcu)
{
	if (rcu)
		return ERR_PTR(-ECHILD);

	/* TODO: init_user_ns? */
	return ntfs_get_acl_ex(&init_user_ns, inode, type, 0);
}

static noinline int ntfs_set_acl_ex(struct user_namespace *mnt_userns,
				    struct inode *inode, struct posix_acl *acl,
				    int type)
{
	const char *name;
	size_t size, name_len;
	void *value = NULL;
	int err = 0;
	int flags;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch (type) {
	case ACL_TYPE_ACCESS:
		if (acl) {
			umode_t mode = inode->i_mode;

			err = posix_acl_update_mode(mnt_userns, inode, &mode,
						    &acl);
			if (err)
				goto out;

			if (inode->i_mode != mode) {
				inode->i_mode = mode;
				mark_inode_dirty(inode);
			}
		}
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
		break;

	case ACL_TYPE_DEFAULT:
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		name = XATTR_NAME_POSIX_ACL_DEFAULT;
		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
		break;

	default:
		return -EINVAL;
	}

	if (!acl) {
		/* Remove xattr if it can be presented via mode. */
		size = 0;
		value = NULL;
		flags = XATTR_REPLACE;
	} else {
		size = posix_acl_xattr_size(acl->a_count);
		value = kmalloc(size, GFP_NOFS);
		if (!value)
			return -ENOMEM;
		err = posix_acl_to_xattr(mnt_userns, acl, value, size);
		if (err < 0)
			goto out;
		flags = 0;
	}

	err = ntfs_set_ea(inode, name, name_len, value, size, flags);
	if (err == -ENODATA && !size)
		err = 0; /* Removing non existed xattr. */
	if (!err)
		set_cached_acl(inode, type, acl);

out:
	kfree(value);

	return err;
}

/*
 * ntfs_set_acl - inode_operations::set_acl
 */
int ntfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
		 struct posix_acl *acl, int type)
{
	return ntfs_set_acl_ex(mnt_userns, inode, acl, type);
}

/*
 * ntfs_init_acl - Initialize the ACLs of a new inode.
 *
 * Called from ntfs_create_inode().
 */
int ntfs_init_acl(struct user_namespace *mnt_userns, struct inode *inode,
		  struct inode *dir)
{
	struct posix_acl *default_acl, *acl;
	int err;

	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
	if (err)
		return err;

	if (default_acl) {
		err = ntfs_set_acl_ex(mnt_userns, inode, default_acl,
				      ACL_TYPE_DEFAULT);
		posix_acl_release(default_acl);
	} else {
		inode->i_default_acl = NULL;
	}

	if (!acl)
		inode->i_acl = NULL;
	else {
		if (!err)
			err = ntfs_set_acl_ex(mnt_userns, inode, acl,
					      ACL_TYPE_ACCESS);
		posix_acl_release(acl);
	}

	return err;
}
#endif

/*
 * ntfs_acl_chmod - Helper for ntfs3_setattr().
 */
int ntfs_acl_chmod(struct user_namespace *mnt_userns, struct inode *inode)
{
	struct super_block *sb = inode->i_sb;

	if (!(sb->s_flags & SB_POSIXACL))
		return 0;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	return posix_acl_chmod(mnt_userns, inode, inode->i_mode);
}

/*
 * ntfs_permission - inode_operations::permission
 */
int ntfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
		    int mask)
{
	if (ntfs_sb(inode->i_sb)->options->noacsrules) {
		/* "No access rules" mode - Allow all changes. */
		return 0;
	}

	return generic_permission(mnt_userns, inode, mask);
}

/*
 * ntfs_listxattr - inode_operations::listxattr
 */
ssize_t ntfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
{
	struct inode *inode = d_inode(dentry);
	struct ntfs_inode *ni = ntfs_i(inode);
	ssize_t ret;

	if (!(ni->ni_flags & NI_FLAG_EA)) {
		/* no xattr in file */
		return 0;
	}

	ni_lock(ni);

	ret = ntfs_list_ea(ni, buffer, size);

	ni_unlock(ni);

	return ret;
}

static int ntfs_getxattr(const struct xattr_handler *handler, struct dentry *de,
			 struct inode *inode, const char *name, void *buffer,
			 size_t size)
{
	int err;
	struct ntfs_inode *ni = ntfs_i(inode);
	size_t name_len = strlen(name);

	/* Dispatch request. */
	if (name_len == sizeof(SYSTEM_DOS_ATTRIB) - 1 &&
	    !memcmp(name, SYSTEM_DOS_ATTRIB, sizeof(SYSTEM_DOS_ATTRIB))) {
		/* system.dos_attrib */
		if (!buffer) {
			err = sizeof(u8);
		} else if (size < sizeof(u8)) {
			err = -ENODATA;
		} else {
			err = sizeof(u8);
			*(u8 *)buffer = le32_to_cpu(ni->std_fa);
		}
		goto out;
	}

	if (name_len == sizeof(SYSTEM_NTFS_ATTRIB) - 1 &&
	    !memcmp(name, SYSTEM_NTFS_ATTRIB, sizeof(SYSTEM_NTFS_ATTRIB))) {
		/* system.ntfs_attrib */
		if (!buffer) {
			err = sizeof(u32);
		} else if (size < sizeof(u32)) {
			err = -ENODATA;
		} else {
			err = sizeof(u32);
			*(u32 *)buffer = le32_to_cpu(ni->std_fa);
		}
		goto out;
	}

	if (name_len == sizeof(SYSTEM_NTFS_SECURITY) - 1 &&
	    !memcmp(name, SYSTEM_NTFS_SECURITY, sizeof(SYSTEM_NTFS_SECURITY))) {
		/* system.ntfs_security*/
		struct SECURITY_DESCRIPTOR_RELATIVE *sd = NULL;
		size_t sd_size = 0;

		if (!is_ntfs3(ni->mi.sbi)) {
			/* We should get nt4 security. */
			err = -EINVAL;
			goto out;
		} else if (le32_to_cpu(ni->std_security_id) <
			   SECURITY_ID_FIRST) {
			err = -ENOENT;
			goto out;
		}

		err = ntfs_get_security_by_id(ni->mi.sbi, ni->std_security_id,
					      &sd, &sd_size);
		if (err)
			goto out;

		if (!is_sd_valid(sd, sd_size)) {
			ntfs_inode_warn(
				inode,
				"looks like you get incorrect security descriptor id=%u",
				ni->std_security_id);
		}

		if (!buffer) {
			err = sd_size;
		} else if (size < sd_size) {
			err = -ENODATA;
		} else {
			err = sd_size;
			memcpy(buffer, sd, sd_size);
		}
		kfree(sd);
		goto out;
	}

	/* Deal with NTFS extended attribute. */
	err = ntfs_get_ea(inode, name, name_len, buffer, size, NULL);

out:
	return err;
}

/*
 * ntfs_setxattr - inode_operations::setxattr
 */
static noinline int 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)
{
	int err = -EINVAL;
	struct ntfs_inode *ni = ntfs_i(inode);
	size_t name_len = strlen(name);
	enum FILE_ATTRIBUTE new_fa;

	/* Dispatch request. */
	if (name_len == sizeof(SYSTEM_DOS_ATTRIB) - 1 &&
	    !memcmp(name, SYSTEM_DOS_ATTRIB, sizeof(SYSTEM_DOS_ATTRIB))) {
		if (sizeof(u8) != size)
			goto out;
		new_fa = cpu_to_le32(*(u8 *)value);
		goto set_new_fa;
	}

	if (name_len == sizeof(SYSTEM_NTFS_ATTRIB) - 1 &&
	    !memcmp(name, SYSTEM_NTFS_ATTRIB, sizeof(SYSTEM_NTFS_ATTRIB))) {
		if (size != sizeof(u32))
			goto out;
		new_fa = cpu_to_le32(*(u32 *)value);

		if (S_ISREG(inode->i_mode)) {
			/* Process compressed/sparsed in special way. */
			ni_lock(ni);
			err = ni_new_attr_flags(ni, new_fa);
			ni_unlock(ni);
			if (err)
				goto out;
		}
set_new_fa:
		/*
		 * Thanks Mark Harmstone:
		 * Keep directory bit consistency.
		 */
		if (S_ISDIR(inode->i_mode))
			new_fa |= FILE_ATTRIBUTE_DIRECTORY;
		else
			new_fa &= ~FILE_ATTRIBUTE_DIRECTORY;

		if (ni->std_fa != new_fa) {
			ni->std_fa = new_fa;
			if (new_fa & FILE_ATTRIBUTE_READONLY)
				inode->i_mode &= ~0222;
			else
				inode->i_mode |= 0222;
			/* Std attribute always in primary record. */
			ni->mi.dirty = true;
			mark_inode_dirty(inode);
		}
		err = 0;

		goto out;
	}

	if (name_len == sizeof(SYSTEM_NTFS_SECURITY) - 1 &&
	    !memcmp(name, SYSTEM_NTFS_SECURITY, sizeof(SYSTEM_NTFS_SECURITY))) {
		/* system.ntfs_security*/
		__le32 security_id;
		bool inserted;
		struct ATTR_STD_INFO5 *std;

		if (!is_ntfs3(ni->mi.sbi)) {
			/*
			 * We should replace ATTR_SECURE.
			 * Skip this way cause it is nt4 feature.
			 */
			err = -EINVAL;
			goto out;
		}

		if (!is_sd_valid(value, size)) {
			err = -EINVAL;
			ntfs_inode_warn(
				inode,
				"you try to set invalid security descriptor");
			goto out;
		}

		err = ntfs_insert_security(ni->mi.sbi, value, size,
					   &security_id, &inserted);
		if (err)
			goto out;

		ni_lock(ni);
		std = ni_std5(ni);
		if (!std) {
			err = -EINVAL;
		} else if (std->security_id != security_id) {
			std->security_id = ni->std_security_id = security_id;
			/* Std attribute always in primary record. */
			ni->mi.dirty = true;
			mark_inode_dirty(&ni->vfs_inode);
		}
		ni_unlock(ni);
		goto out;
	}

	/* Deal with NTFS extended attribute. */
	err = ntfs_set_ea(inode, name, name_len, value, size, flags);

out:
	return err;
}

/*
 * ntfs_save_wsl_perm
 *
 * save uid/gid/mode in xattr
 */
int ntfs_save_wsl_perm(struct inode *inode)
{
	int err;
	__le32 value;

	/* TODO: refactor this, so we don't lock 4 times in ntfs_set_ea */
	value = cpu_to_le32(i_uid_read(inode));
	err = ntfs_set_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value,
			  sizeof(value), 0);
	if (err)
		goto out;

	value = cpu_to_le32(i_gid_read(inode));
	err = ntfs_set_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value,
			  sizeof(value), 0);
	if (err)
		goto out;

	value = cpu_to_le32(inode->i_mode);
	err = ntfs_set_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value,
			  sizeof(value), 0);
	if (err)
		goto out;

	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
		value = cpu_to_le32(inode->i_rdev);
		err = ntfs_set_ea(inode, "$LXDEV", sizeof("$LXDEV") - 1, &value,
				  sizeof(value), 0);
		if (err)
			goto out;
	}

out:
	/* In case of error should we delete all WSL xattr? */
	return err;
}

/*
 * ntfs_get_wsl_perm
 *
 * get uid/gid/mode from xattr
 * it is called from ntfs_iget5->ntfs_read_mft
 */
void ntfs_get_wsl_perm(struct inode *inode)
{
	size_t sz;
	__le32 value[3];

	if (ntfs_get_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value[0],
			sizeof(value[0]), &sz) == sizeof(value[0]) &&
	    ntfs_get_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value[1],
			sizeof(value[1]), &sz) == sizeof(value[1]) &&
	    ntfs_get_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value[2],
			sizeof(value[2]), &sz) == sizeof(value[2])) {
		i_uid_write(inode, (uid_t)le32_to_cpu(value[0]));
		i_gid_write(inode, (gid_t)le32_to_cpu(value[1]));
		inode->i_mode = le32_to_cpu(value[2]);

		if (ntfs_get_ea(inode, "$LXDEV", sizeof("$$LXDEV") - 1,
				&value[0], sizeof(value),
				&sz) == sizeof(value[0])) {
			inode->i_rdev = le32_to_cpu(value[0]);
		}
	}
}

static bool ntfs_xattr_user_list(struct dentry *dentry)
{
	return true;
}

// clang-format off
static const struct xattr_handler ntfs_xattr_handler = {
	.prefix	= "",
	.get	= ntfs_getxattr,
	.set	= ntfs_setxattr,
	.list	= ntfs_xattr_user_list,
};

const struct xattr_handler *ntfs_xattr_handlers[] = {
	&ntfs_xattr_handler,
	NULL,
};
// clang-format on