xref: /openbmc/linux/fs/ntfs3/xattr.c (revision 1cc1e4c8)
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 
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 
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  */
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  */
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  */
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 
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 
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
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  */
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 
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  */
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  */
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  */
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  */
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  */
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 
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  */
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  */
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("$LXDEV") - 1, &value,
939 				  sizeof(value), 0);
940 		if (err)
941 			goto out;
942 	}
943 
944 out:
945 	/* In case of error should we delete all WSL xattr? */
946 	return err;
947 }
948 
949 /*
950  * ntfs_get_wsl_perm
951  *
952  * get uid/gid/mode from xattr
953  * it is called from ntfs_iget5->ntfs_read_mft
954  */
955 void ntfs_get_wsl_perm(struct inode *inode)
956 {
957 	size_t sz;
958 	__le32 value[3];
959 
960 	if (ntfs_get_ea(inode, "$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 
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