xref: /linux/fs/ntfs3/xattr.c (revision f4738f56d1dc62aaba69b33702a5ab098f1b8c63)
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_ATTRIB_BE "system.ntfs_attrib_be"
21 #define SYSTEM_NTFS_SECURITY  "system.ntfs_security"
22 // clang-format on
23 
24 static inline size_t unpacked_ea_size(const struct EA_FULL *ea)
25 {
26 	return ea->size ? le32_to_cpu(ea->size) :
27 			  ALIGN(struct_size(ea, name,
28 					    1 + ea->name_len +
29 						    le16_to_cpu(ea->elength)),
30 				4);
31 }
32 
33 static inline size_t packed_ea_size(const struct EA_FULL *ea)
34 {
35 	return struct_size(ea, name,
36 			   1 + ea->name_len + le16_to_cpu(ea->elength)) -
37 	       offsetof(struct EA_FULL, flags);
38 }
39 
40 /*
41  * find_ea
42  *
43  * Assume there is at least one xattr in the list.
44  */
45 static inline bool find_ea(const struct EA_FULL *ea_all, u32 bytes,
46 			   const char *name, u8 name_len, u32 *off, u32 *ea_sz)
47 {
48 	u32 ea_size;
49 
50 	*off = 0;
51 	if (!ea_all)
52 		return false;
53 
54 	for (; *off < bytes; *off += ea_size) {
55 		const struct EA_FULL *ea = Add2Ptr(ea_all, *off);
56 		ea_size = unpacked_ea_size(ea);
57 		if (ea->name_len == name_len &&
58 		    !memcmp(ea->name, name, name_len)) {
59 			if (ea_sz)
60 				*ea_sz = ea_size;
61 			return true;
62 		}
63 	}
64 
65 	return false;
66 }
67 
68 /*
69  * ntfs_read_ea - Read all extended attributes.
70  * @ea:		New allocated memory.
71  * @info:	Pointer into resident data.
72  */
73 static int ntfs_read_ea(struct ntfs_inode *ni, struct EA_FULL **ea,
74 			size_t add_bytes, const struct EA_INFO **info)
75 {
76 	int err = -EINVAL;
77 	struct ntfs_sb_info *sbi = ni->mi.sbi;
78 	struct ATTR_LIST_ENTRY *le = NULL;
79 	struct ATTRIB *attr_info, *attr_ea;
80 	void *ea_p;
81 	u32 size, off, ea_size;
82 
83 	static_assert(le32_to_cpu(ATTR_EA_INFO) < le32_to_cpu(ATTR_EA));
84 
85 	*ea = NULL;
86 	*info = NULL;
87 
88 	attr_info =
89 		ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, NULL);
90 	attr_ea =
91 		ni_find_attr(ni, attr_info, &le, ATTR_EA, NULL, 0, NULL, NULL);
92 
93 	if (!attr_ea || !attr_info)
94 		return 0;
95 
96 	*info = resident_data_ex(attr_info, sizeof(struct EA_INFO));
97 	if (!*info)
98 		goto out;
99 
100 	/* Check Ea limit. */
101 	size = le32_to_cpu((*info)->size);
102 	if (size > sbi->ea_max_size) {
103 		err = -EFBIG;
104 		goto out;
105 	}
106 
107 	if (attr_size(attr_ea) > sbi->ea_max_size) {
108 		err = -EFBIG;
109 		goto out;
110 	}
111 
112 	if (!size) {
113 		/* EA info persists, but xattr is empty. Looks like EA problem. */
114 		goto out;
115 	}
116 
117 	/* Allocate memory for packed Ea. */
118 	ea_p = kmalloc(size_add(size, add_bytes), GFP_NOFS);
119 	if (!ea_p)
120 		return -ENOMEM;
121 
122 	if (attr_ea->non_res) {
123 		struct runs_tree run;
124 
125 		run_init(&run);
126 
127 		err = attr_load_runs_range(ni, ATTR_EA, NULL, 0, &run, 0, size);
128 		if (!err)
129 			err = ntfs_read_run_nb(sbi, &run, 0, ea_p, size, NULL);
130 		run_close(&run);
131 
132 		if (err)
133 			goto out1;
134 	} else {
135 		void *p = resident_data_ex(attr_ea, size);
136 
137 		if (!p)
138 			goto out1;
139 		memcpy(ea_p, p, size);
140 	}
141 
142 	memset(Add2Ptr(ea_p, size), 0, add_bytes);
143 
144 	err = -EINVAL;
145 	/* Check all attributes for consistency. */
146 	for (off = 0; off < size; off += ea_size) {
147 		const struct EA_FULL *ef = Add2Ptr(ea_p, off);
148 		u32 bytes = size - off;
149 
150 		/* Check if we can use field ea->size. */
151 		if (bytes < sizeof(ef->size))
152 			goto out1;
153 
154 		if (ef->size) {
155 			ea_size = le32_to_cpu(ef->size);
156 			if (ea_size > bytes)
157 				goto out1;
158 			continue;
159 		}
160 
161 		/* Check if we can use fields ef->name_len and ef->elength. */
162 		if (bytes < offsetof(struct EA_FULL, name))
163 			goto out1;
164 
165 		ea_size = ALIGN(struct_size(ef, name,
166 					    1 + ef->name_len +
167 						    le16_to_cpu(ef->elength)),
168 				4);
169 		if (ea_size > bytes)
170 			goto out1;
171 	}
172 
173 	*ea = ea_p;
174 	return 0;
175 
176 out1:
177 	kfree(ea_p);
178 out:
179 	ntfs_set_state(sbi, NTFS_DIRTY_DIRTY);
180 	return err;
181 }
182 
183 /*
184  * ntfs_list_ea
185  *
186  * Copy a list of xattrs names into the buffer
187  * provided, or compute the buffer size required.
188  *
189  * Return:
190  * * Number of bytes used / required on
191  * * -ERRNO - on failure
192  */
193 static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
194 			    size_t bytes_per_buffer)
195 {
196 	const struct EA_INFO *info;
197 	struct EA_FULL *ea_all = NULL;
198 	const struct EA_FULL *ea;
199 	u32 off, size;
200 	int err;
201 	int ea_size;
202 	size_t ret;
203 
204 	err = ntfs_read_ea(ni, &ea_all, 0, &info);
205 	if (err)
206 		return err;
207 
208 	if (!info || !ea_all)
209 		return 0;
210 
211 	size = le32_to_cpu(info->size);
212 
213 	/* Enumerate all xattrs. */
214 	for (ret = 0, off = 0; off < size; off += ea_size) {
215 		ea = Add2Ptr(ea_all, off);
216 		ea_size = unpacked_ea_size(ea);
217 
218 		if (!ea->name_len)
219 			break;
220 
221 		if (buffer) {
222 			if (ret + ea->name_len + 1 > bytes_per_buffer) {
223 				err = -ERANGE;
224 				goto out;
225 			}
226 
227 			memcpy(buffer + ret, ea->name, ea->name_len);
228 			buffer[ret + ea->name_len] = 0;
229 		}
230 
231 		ret += ea->name_len + 1;
232 	}
233 
234 out:
235 	kfree(ea_all);
236 	return err ? err : ret;
237 }
238 
239 static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
240 		       void *buffer, size_t size, size_t *required)
241 {
242 	struct ntfs_inode *ni = ntfs_i(inode);
243 	const struct EA_INFO *info;
244 	struct EA_FULL *ea_all = NULL;
245 	const struct EA_FULL *ea;
246 	u32 off, len;
247 	int err;
248 
249 	if (!(ni->ni_flags & NI_FLAG_EA))
250 		return -ENODATA;
251 
252 	if (!required)
253 		ni_lock(ni);
254 
255 	len = 0;
256 
257 	if (name_len > 255) {
258 		err = -ENAMETOOLONG;
259 		goto out;
260 	}
261 
262 	err = ntfs_read_ea(ni, &ea_all, 0, &info);
263 	if (err)
264 		goto out;
265 
266 	if (!info)
267 		goto out;
268 
269 	/* Enumerate all xattrs. */
270 	if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off,
271 		     NULL)) {
272 		err = -ENODATA;
273 		goto out;
274 	}
275 	ea = Add2Ptr(ea_all, off);
276 
277 	len = le16_to_cpu(ea->elength);
278 	if (!buffer) {
279 		err = 0;
280 		goto out;
281 	}
282 
283 	if (len > size) {
284 		err = -ERANGE;
285 		if (required)
286 			*required = len;
287 		goto out;
288 	}
289 
290 	memcpy(buffer, ea->name + ea->name_len + 1, len);
291 	err = 0;
292 
293 out:
294 	kfree(ea_all);
295 	if (!required)
296 		ni_unlock(ni);
297 
298 	return err ? err : len;
299 }
300 
301 static noinline int ntfs_set_ea(struct inode *inode, const char *name,
302 				size_t name_len, const void *value,
303 				size_t val_size, int flags, bool locked,
304 				__le16 *ea_size)
305 {
306 	struct ntfs_inode *ni = ntfs_i(inode);
307 	struct ntfs_sb_info *sbi = ni->mi.sbi;
308 	int err;
309 	struct EA_INFO ea_info;
310 	const struct EA_INFO *info;
311 	struct EA_FULL *new_ea;
312 	struct EA_FULL *ea_all = NULL;
313 	size_t add, new_pack;
314 	u32 off, size, ea_sz;
315 	__le16 size_pack;
316 	struct ATTRIB *attr;
317 	struct ATTR_LIST_ENTRY *le;
318 	struct mft_inode *mi;
319 	struct runs_tree ea_run;
320 	u64 new_sz;
321 	void *p;
322 
323 	if (!locked)
324 		ni_lock(ni);
325 
326 	run_init(&ea_run);
327 
328 	if (name_len > 255) {
329 		err = -ENAMETOOLONG;
330 		goto out;
331 	}
332 
333 	add = ALIGN(struct_size(ea_all, name, 1 + name_len + val_size), 4);
334 
335 	err = ntfs_read_ea(ni, &ea_all, add, &info);
336 	if (err)
337 		goto out;
338 
339 	if (!info) {
340 		memset(&ea_info, 0, sizeof(ea_info));
341 		size = 0;
342 		size_pack = 0;
343 	} else {
344 		memcpy(&ea_info, info, sizeof(ea_info));
345 		size = le32_to_cpu(ea_info.size);
346 		size_pack = ea_info.size_pack;
347 	}
348 
349 	if (info && find_ea(ea_all, size, name, name_len, &off, &ea_sz)) {
350 		struct EA_FULL *ea;
351 
352 		if (flags & XATTR_CREATE) {
353 			err = -EEXIST;
354 			goto out;
355 		}
356 
357 		ea = Add2Ptr(ea_all, off);
358 
359 		/*
360 		 * Check simple case when we try to insert xattr with the same value
361 		 * e.g. ntfs_save_wsl_perm
362 		 */
363 		if (val_size && le16_to_cpu(ea->elength) == val_size &&
364 		    !memcmp(ea->name + ea->name_len + 1, value, val_size)) {
365 			/* xattr already contains the required value. */
366 			goto out;
367 		}
368 
369 		/* Remove current xattr. */
370 		if (ea->flags & FILE_NEED_EA)
371 			le16_add_cpu(&ea_info.count, -1);
372 
373 		le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));
374 
375 		memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);
376 
377 		size -= ea_sz;
378 		memset(Add2Ptr(ea_all, size), 0, ea_sz);
379 
380 		ea_info.size = cpu_to_le32(size);
381 
382 		if ((flags & XATTR_REPLACE) && !val_size) {
383 			/* Remove xattr. */
384 			goto update_ea;
385 		}
386 	} else {
387 		if (flags & XATTR_REPLACE) {
388 			err = -ENODATA;
389 			goto out;
390 		}
391 
392 		if (!ea_all) {
393 			ea_all = kzalloc(add, GFP_NOFS);
394 			if (!ea_all) {
395 				err = -ENOMEM;
396 				goto out;
397 			}
398 		}
399 	}
400 
401 	/* Append new xattr. */
402 	new_ea = Add2Ptr(ea_all, size);
403 	new_ea->size = cpu_to_le32(add);
404 	new_ea->flags = 0;
405 	new_ea->name_len = name_len;
406 	new_ea->elength = cpu_to_le16(val_size);
407 	memcpy(new_ea->name, name, name_len);
408 	new_ea->name[name_len] = 0;
409 	memcpy(new_ea->name + name_len + 1, value, val_size);
410 	new_pack = le16_to_cpu(ea_info.size_pack) + packed_ea_size(new_ea);
411 	ea_info.size_pack = cpu_to_le16(new_pack);
412 	/* New size of ATTR_EA. */
413 	size += add;
414 	ea_info.size = cpu_to_le32(size);
415 
416 	/*
417 	 * 1. Check ea_info.size_pack for overflow.
418 	 * 2. New attribute size must fit value from $AttrDef
419 	 */
420 	if (new_pack > 0xffff || size > sbi->ea_max_size) {
421 		ntfs_inode_warn(
422 			inode,
423 			"The size of extended attributes must not exceed 64KiB");
424 		err = -EFBIG; // -EINVAL?
425 		goto out;
426 	}
427 
428 update_ea:
429 
430 	if (!info) {
431 		/* Create xattr. */
432 		if (!size) {
433 			err = 0;
434 			goto out;
435 		}
436 
437 		err = ni_insert_resident(ni, sizeof(struct EA_INFO),
438 					 ATTR_EA_INFO, NULL, 0, NULL, NULL,
439 					 NULL);
440 		if (err)
441 			goto out;
442 
443 		err = ni_insert_resident(ni, 0, ATTR_EA, NULL, 0, NULL, NULL,
444 					 NULL);
445 		if (err)
446 			goto out;
447 	}
448 
449 	new_sz = size;
450 	err = attr_set_size(ni, ATTR_EA, NULL, 0, &ea_run, new_sz, &new_sz,
451 			    false, NULL);
452 	if (err)
453 		goto out;
454 
455 	le = NULL;
456 	attr = ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, &mi);
457 	if (!attr) {
458 		err = -EINVAL;
459 		goto out;
460 	}
461 
462 	if (!size) {
463 		/* Delete xattr, ATTR_EA_INFO */
464 		ni_remove_attr_le(ni, attr, mi, le);
465 	} else {
466 		p = resident_data_ex(attr, sizeof(struct EA_INFO));
467 		if (!p) {
468 			err = -EINVAL;
469 			goto out;
470 		}
471 		memcpy(p, &ea_info, sizeof(struct EA_INFO));
472 		mi->dirty = true;
473 	}
474 
475 	le = NULL;
476 	attr = ni_find_attr(ni, NULL, &le, ATTR_EA, NULL, 0, NULL, &mi);
477 	if (!attr) {
478 		err = -EINVAL;
479 		goto out;
480 	}
481 
482 	if (!size) {
483 		/* Delete xattr, ATTR_EA */
484 		ni_remove_attr_le(ni, attr, mi, le);
485 	} else if (attr->non_res) {
486 		err = attr_load_runs_range(ni, ATTR_EA, NULL, 0, &ea_run, 0,
487 					   size);
488 		if (err)
489 			goto out;
490 
491 		err = ntfs_sb_write_run(sbi, &ea_run, 0, ea_all, size, 0);
492 		if (err)
493 			goto out;
494 	} else {
495 		p = resident_data_ex(attr, size);
496 		if (!p) {
497 			err = -EINVAL;
498 			goto out;
499 		}
500 		memcpy(p, ea_all, size);
501 		mi->dirty = true;
502 	}
503 
504 	/* Check if we delete the last xattr. */
505 	if (size)
506 		ni->ni_flags |= NI_FLAG_EA;
507 	else
508 		ni->ni_flags &= ~NI_FLAG_EA;
509 
510 	if (ea_info.size_pack != size_pack)
511 		ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
512 	if (ea_size)
513 		*ea_size = ea_info.size_pack;
514 	mark_inode_dirty(&ni->vfs_inode);
515 
516 out:
517 	if (!locked)
518 		ni_unlock(ni);
519 
520 	run_close(&ea_run);
521 	kfree(ea_all);
522 
523 	return err;
524 }
525 
526 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
527 
528 /*
529  * ntfs_get_acl - inode_operations::get_acl
530  */
531 struct posix_acl *ntfs_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
532 			       int type)
533 {
534 	struct inode *inode = d_inode(dentry);
535 	struct ntfs_inode *ni = ntfs_i(inode);
536 	const char *name;
537 	size_t name_len;
538 	struct posix_acl *acl;
539 	size_t req;
540 	int err;
541 	void *buf;
542 
543 	/* Allocate PATH_MAX bytes. */
544 	buf = __getname();
545 	if (!buf)
546 		return ERR_PTR(-ENOMEM);
547 
548 	/* Possible values of 'type' was already checked above. */
549 	if (type == ACL_TYPE_ACCESS) {
550 		name = XATTR_NAME_POSIX_ACL_ACCESS;
551 		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
552 	} else {
553 		name = XATTR_NAME_POSIX_ACL_DEFAULT;
554 		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
555 	}
556 
557 	ni_lock(ni);
558 
559 	err = ntfs_get_ea(inode, name, name_len, buf, PATH_MAX, &req);
560 
561 	ni_unlock(ni);
562 
563 	/* Translate extended attribute to acl. */
564 	if (err >= 0) {
565 		acl = posix_acl_from_xattr(&init_user_ns, buf, err);
566 	} else if (err == -ENODATA) {
567 		acl = NULL;
568 	} else {
569 		acl = ERR_PTR(err);
570 	}
571 
572 	if (!IS_ERR(acl))
573 		set_cached_acl(inode, type, acl);
574 
575 	__putname(buf);
576 
577 	return acl;
578 }
579 
580 static noinline int ntfs_set_acl_ex(struct mnt_idmap *idmap,
581 				    struct inode *inode, struct posix_acl *acl,
582 				    int type, bool init_acl)
583 {
584 	const char *name;
585 	size_t size, name_len;
586 	void *value;
587 	int err;
588 	int flags;
589 	umode_t mode;
590 
591 	if (S_ISLNK(inode->i_mode))
592 		return -EOPNOTSUPP;
593 
594 	mode = inode->i_mode;
595 	switch (type) {
596 	case ACL_TYPE_ACCESS:
597 		/* Do not change i_mode if we are in init_acl */
598 		if (acl && !init_acl) {
599 			err = posix_acl_update_mode(idmap, inode, &mode, &acl);
600 			if (err)
601 				return err;
602 		}
603 		name = XATTR_NAME_POSIX_ACL_ACCESS;
604 		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
605 		break;
606 
607 	case ACL_TYPE_DEFAULT:
608 		if (!S_ISDIR(inode->i_mode))
609 			return acl ? -EACCES : 0;
610 		name = XATTR_NAME_POSIX_ACL_DEFAULT;
611 		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
612 		break;
613 
614 	default:
615 		return -EINVAL;
616 	}
617 
618 	if (!acl) {
619 		/* Remove xattr if it can be presented via mode. */
620 		size = 0;
621 		value = NULL;
622 		flags = XATTR_REPLACE;
623 	} else {
624 		size = posix_acl_xattr_size(acl->a_count);
625 		value = kmalloc(size, GFP_NOFS);
626 		if (!value)
627 			return -ENOMEM;
628 		err = posix_acl_to_xattr(&init_user_ns, acl, value, size);
629 		if (err < 0)
630 			goto out;
631 		flags = 0;
632 	}
633 
634 	err = ntfs_set_ea(inode, name, name_len, value, size, flags, 0, NULL);
635 	if (err == -ENODATA && !size)
636 		err = 0; /* Removing non existed xattr. */
637 	if (!err) {
638 		set_cached_acl(inode, type, acl);
639 		inode->i_mode = mode;
640 		inode_set_ctime_current(inode);
641 		mark_inode_dirty(inode);
642 	}
643 
644 out:
645 	kfree(value);
646 
647 	return err;
648 }
649 
650 /*
651  * ntfs_set_acl - inode_operations::set_acl
652  */
653 int ntfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
654 		 struct posix_acl *acl, int type)
655 {
656 	return ntfs_set_acl_ex(idmap, d_inode(dentry), acl, type, false);
657 }
658 
659 /*
660  * ntfs_init_acl - Initialize the ACLs of a new inode.
661  *
662  * Called from ntfs_create_inode().
663  */
664 int ntfs_init_acl(struct mnt_idmap *idmap, struct inode *inode,
665 		  struct inode *dir)
666 {
667 	struct posix_acl *default_acl, *acl;
668 	int err;
669 
670 	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
671 	if (err)
672 		return err;
673 
674 	if (default_acl) {
675 		err = ntfs_set_acl_ex(idmap, inode, default_acl,
676 				      ACL_TYPE_DEFAULT, true);
677 		posix_acl_release(default_acl);
678 	} else {
679 		inode->i_default_acl = NULL;
680 	}
681 
682 	if (acl) {
683 		if (!err)
684 			err = ntfs_set_acl_ex(idmap, inode, acl,
685 					      ACL_TYPE_ACCESS, true);
686 		posix_acl_release(acl);
687 	} else {
688 		inode->i_acl = NULL;
689 	}
690 
691 	return err;
692 }
693 #endif
694 
695 /*
696  * ntfs_acl_chmod - Helper for ntfs3_setattr().
697  */
698 int ntfs_acl_chmod(struct mnt_idmap *idmap, struct dentry *dentry)
699 {
700 	struct inode *inode = d_inode(dentry);
701 	struct super_block *sb = inode->i_sb;
702 
703 	if (!(sb->s_flags & SB_POSIXACL))
704 		return 0;
705 
706 	if (S_ISLNK(inode->i_mode))
707 		return -EOPNOTSUPP;
708 
709 	return posix_acl_chmod(idmap, dentry, inode->i_mode);
710 }
711 
712 /*
713  * ntfs_listxattr - inode_operations::listxattr
714  */
715 ssize_t ntfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
716 {
717 	struct inode *inode = d_inode(dentry);
718 	struct ntfs_inode *ni = ntfs_i(inode);
719 	ssize_t ret;
720 
721 	if (!(ni->ni_flags & NI_FLAG_EA)) {
722 		/* no xattr in file */
723 		return 0;
724 	}
725 
726 	ni_lock(ni);
727 
728 	ret = ntfs_list_ea(ni, buffer, size);
729 
730 	ni_unlock(ni);
731 
732 	return ret;
733 }
734 
735 static int ntfs_getxattr(const struct xattr_handler *handler, struct dentry *de,
736 			 struct inode *inode, const char *name, void *buffer,
737 			 size_t size)
738 {
739 	int err;
740 	struct ntfs_inode *ni = ntfs_i(inode);
741 
742 	/* Dispatch request. */
743 	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
744 		/* system.dos_attrib */
745 		if (!buffer) {
746 			err = sizeof(u8);
747 		} else if (size < sizeof(u8)) {
748 			err = -ENODATA;
749 		} else {
750 			err = sizeof(u8);
751 			*(u8 *)buffer = le32_to_cpu(ni->std_fa);
752 		}
753 		goto out;
754 	}
755 
756 	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
757 	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
758 		/* system.ntfs_attrib */
759 		if (!buffer) {
760 			err = sizeof(u32);
761 		} else if (size < sizeof(u32)) {
762 			err = -ENODATA;
763 		} else {
764 			err = sizeof(u32);
765 			*(u32 *)buffer = le32_to_cpu(ni->std_fa);
766 			if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
767 				*(__be32 *)buffer = cpu_to_be32(*(u32 *)buffer);
768 		}
769 		goto out;
770 	}
771 
772 	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
773 		/* system.ntfs_security*/
774 		struct SECURITY_DESCRIPTOR_RELATIVE *sd = NULL;
775 		size_t sd_size = 0;
776 
777 		if (!is_ntfs3(ni->mi.sbi)) {
778 			/* We should get nt4 security. */
779 			err = -EINVAL;
780 			goto out;
781 		} else if (le32_to_cpu(ni->std_security_id) <
782 			   SECURITY_ID_FIRST) {
783 			err = -ENOENT;
784 			goto out;
785 		}
786 
787 		err = ntfs_get_security_by_id(ni->mi.sbi, ni->std_security_id,
788 					      &sd, &sd_size);
789 		if (err)
790 			goto out;
791 
792 		if (!is_sd_valid(sd, sd_size)) {
793 			ntfs_inode_warn(
794 				inode,
795 				"looks like you get incorrect security descriptor id=%u",
796 				ni->std_security_id);
797 		}
798 
799 		if (!buffer) {
800 			err = sd_size;
801 		} else if (size < sd_size) {
802 			err = -ENODATA;
803 		} else {
804 			err = sd_size;
805 			memcpy(buffer, sd, sd_size);
806 		}
807 		kfree(sd);
808 		goto out;
809 	}
810 
811 	/* Deal with NTFS extended attribute. */
812 	err = ntfs_get_ea(inode, name, strlen(name), buffer, size, NULL);
813 
814 out:
815 	return err;
816 }
817 
818 /*
819  * ntfs_setxattr - inode_operations::setxattr
820  */
821 static noinline int ntfs_setxattr(const struct xattr_handler *handler,
822 				  struct mnt_idmap *idmap, struct dentry *de,
823 				  struct inode *inode, const char *name,
824 				  const void *value, size_t size, int flags)
825 {
826 	int err = -EINVAL;
827 	struct ntfs_inode *ni = ntfs_i(inode);
828 	enum FILE_ATTRIBUTE new_fa;
829 
830 	/* Dispatch request. */
831 	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
832 		if (sizeof(u8) != size)
833 			goto out;
834 		new_fa = cpu_to_le32(*(u8 *)value);
835 		goto set_new_fa;
836 	}
837 
838 	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
839 	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
840 		if (size != sizeof(u32))
841 			goto out;
842 		if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
843 			new_fa = cpu_to_le32(be32_to_cpu(*(__be32 *)value));
844 		else
845 			new_fa = cpu_to_le32(*(u32 *)value);
846 
847 		if (S_ISREG(inode->i_mode)) {
848 			/* Process compressed/sparsed in special way. */
849 			ni_lock(ni);
850 			err = ni_new_attr_flags(ni, new_fa);
851 			ni_unlock(ni);
852 			if (err)
853 				goto out;
854 		}
855 set_new_fa:
856 		/*
857 		 * Thanks Mark Harmstone:
858 		 * Keep directory bit consistency.
859 		 */
860 		if (S_ISDIR(inode->i_mode))
861 			new_fa |= FILE_ATTRIBUTE_DIRECTORY;
862 		else
863 			new_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
864 
865 		if (ni->std_fa != new_fa) {
866 			ni->std_fa = new_fa;
867 			if (new_fa & FILE_ATTRIBUTE_READONLY)
868 				inode->i_mode &= ~0222;
869 			else
870 				inode->i_mode |= 0222;
871 			/* Std attribute always in primary record. */
872 			ni->mi.dirty = true;
873 			mark_inode_dirty(inode);
874 		}
875 		err = 0;
876 
877 		goto out;
878 	}
879 
880 	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
881 		/* system.ntfs_security*/
882 		__le32 security_id;
883 		bool inserted;
884 		struct ATTR_STD_INFO5 *std;
885 
886 		if (!is_ntfs3(ni->mi.sbi)) {
887 			/*
888 			 * We should replace ATTR_SECURE.
889 			 * Skip this way cause it is nt4 feature.
890 			 */
891 			err = -EINVAL;
892 			goto out;
893 		}
894 
895 		if (!is_sd_valid(value, size)) {
896 			err = -EINVAL;
897 			ntfs_inode_warn(
898 				inode,
899 				"you try to set invalid security descriptor");
900 			goto out;
901 		}
902 
903 		err = ntfs_insert_security(ni->mi.sbi, value, size,
904 					   &security_id, &inserted);
905 		if (err)
906 			goto out;
907 
908 		ni_lock(ni);
909 		std = ni_std5(ni);
910 		if (!std) {
911 			err = -EINVAL;
912 		} else if (std->security_id != security_id) {
913 			std->security_id = ni->std_security_id = security_id;
914 			/* Std attribute always in primary record. */
915 			ni->mi.dirty = true;
916 			mark_inode_dirty(&ni->vfs_inode);
917 		}
918 		ni_unlock(ni);
919 		goto out;
920 	}
921 
922 	/* Deal with NTFS extended attribute. */
923 	err = ntfs_set_ea(inode, name, strlen(name), value, size, flags, 0,
924 			  NULL);
925 
926 out:
927 	inode_set_ctime_current(inode);
928 	mark_inode_dirty(inode);
929 
930 	return err;
931 }
932 
933 /*
934  * ntfs_save_wsl_perm
935  *
936  * save uid/gid/mode in xattr
937  */
938 int ntfs_save_wsl_perm(struct inode *inode, __le16 *ea_size)
939 {
940 	int err;
941 	__le32 value;
942 	struct ntfs_inode *ni = ntfs_i(inode);
943 
944 	ni_lock(ni);
945 	value = cpu_to_le32(i_uid_read(inode));
946 	err = ntfs_set_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value,
947 			  sizeof(value), 0, true, ea_size);
948 	if (err)
949 		goto out;
950 
951 	value = cpu_to_le32(i_gid_read(inode));
952 	err = ntfs_set_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value,
953 			  sizeof(value), 0, true, ea_size);
954 	if (err)
955 		goto out;
956 
957 	value = cpu_to_le32(inode->i_mode);
958 	err = ntfs_set_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value,
959 			  sizeof(value), 0, true, ea_size);
960 	if (err)
961 		goto out;
962 
963 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
964 		value = cpu_to_le32(inode->i_rdev);
965 		err = ntfs_set_ea(inode, "$LXDEV", sizeof("$LXDEV") - 1, &value,
966 				  sizeof(value), 0, true, ea_size);
967 		if (err)
968 			goto out;
969 	}
970 
971 out:
972 	ni_unlock(ni);
973 	/* In case of error should we delete all WSL xattr? */
974 	return err;
975 }
976 
977 /*
978  * ntfs_get_wsl_perm
979  *
980  * get uid/gid/mode from xattr
981  * it is called from ntfs_iget5->ntfs_read_mft
982  */
983 void ntfs_get_wsl_perm(struct inode *inode)
984 {
985 	size_t sz;
986 	__le32 value[3];
987 
988 	if (ntfs_get_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value[0],
989 			sizeof(value[0]), &sz) == sizeof(value[0]) &&
990 	    ntfs_get_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value[1],
991 			sizeof(value[1]), &sz) == sizeof(value[1]) &&
992 	    ntfs_get_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value[2],
993 			sizeof(value[2]), &sz) == sizeof(value[2])) {
994 		i_uid_write(inode, (uid_t)le32_to_cpu(value[0]));
995 		i_gid_write(inode, (gid_t)le32_to_cpu(value[1]));
996 		inode->i_mode = le32_to_cpu(value[2]);
997 
998 		if (ntfs_get_ea(inode, "$LXDEV", sizeof("$$LXDEV") - 1,
999 				&value[0], sizeof(value),
1000 				&sz) == sizeof(value[0])) {
1001 			inode->i_rdev = le32_to_cpu(value[0]);
1002 		}
1003 	}
1004 }
1005 
1006 static bool ntfs_xattr_user_list(struct dentry *dentry)
1007 {
1008 	return true;
1009 }
1010 
1011 // clang-format off
1012 static const struct xattr_handler ntfs_other_xattr_handler = {
1013 	.prefix	= "",
1014 	.get	= ntfs_getxattr,
1015 	.set	= ntfs_setxattr,
1016 	.list	= ntfs_xattr_user_list,
1017 };
1018 
1019 const struct xattr_handler *ntfs_xattr_handlers[] = {
1020 	&ntfs_other_xattr_handler,
1021 	NULL,
1022 };
1023 // clang-format on
1024