xref: /linux/fs/ntfs3/xattr.c (revision 689ecd06)
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 
unpacked_ea_size(const struct EA_FULL * ea)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 
packed_ea_size(const struct EA_FULL * ea)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  */
find_ea(const struct EA_FULL * ea_all,u32 bytes,const char * name,u8 name_len,u32 * off,u32 * ea_sz)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  */
ntfs_read_ea(struct ntfs_inode * ni,struct EA_FULL ** ea,size_t add_bytes,const struct EA_INFO ** info)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  */
ntfs_list_ea(struct ntfs_inode * ni,char * buffer,size_t bytes_per_buffer)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 	u32 off, size;
199 	int err;
200 	size_t ret;
201 
202 	err = ntfs_read_ea(ni, &ea_all, 0, &info);
203 	if (err)
204 		return err;
205 
206 	if (!info || !ea_all)
207 		return 0;
208 
209 	size = le32_to_cpu(info->size);
210 
211 	/* Enumerate all xattrs. */
212 	ret = 0;
213 	off = 0;
214 	while (off + sizeof(struct EA_FULL) < size) {
215 		const struct EA_FULL *ea = Add2Ptr(ea_all, off);
216 		int ea_size = unpacked_ea_size(ea);
217 		u8 name_len = ea->name_len;
218 
219 		if (!name_len)
220 			break;
221 
222 		if (name_len > ea_size) {
223 			ntfs_set_state(ni->mi.sbi, NTFS_DIRTY_ERROR);
224 			err = -EINVAL; /* corrupted fs. */
225 			break;
226 		}
227 
228 		if (buffer) {
229 			/* Check if we can use field ea->name */
230 			if (off + ea_size > size)
231 				break;
232 
233 			if (ret + name_len + 1 > bytes_per_buffer) {
234 				err = -ERANGE;
235 				goto out;
236 			}
237 
238 			memcpy(buffer + ret, ea->name, name_len);
239 			buffer[ret + name_len] = 0;
240 		}
241 
242 		ret += name_len + 1;
243 		off += ea_size;
244 	}
245 
246 out:
247 	kfree(ea_all);
248 	return err ? err : ret;
249 }
250 
ntfs_get_ea(struct inode * inode,const char * name,size_t name_len,void * buffer,size_t size,size_t * required)251 static int ntfs_get_ea(struct inode *inode, const char *name, size_t name_len,
252 		       void *buffer, size_t size, size_t *required)
253 {
254 	struct ntfs_inode *ni = ntfs_i(inode);
255 	const struct EA_INFO *info;
256 	struct EA_FULL *ea_all = NULL;
257 	const struct EA_FULL *ea;
258 	u32 off, len;
259 	int err;
260 
261 	if (!(ni->ni_flags & NI_FLAG_EA))
262 		return -ENODATA;
263 
264 	if (!required)
265 		ni_lock(ni);
266 
267 	len = 0;
268 
269 	if (name_len > 255) {
270 		err = -ENAMETOOLONG;
271 		goto out;
272 	}
273 
274 	err = ntfs_read_ea(ni, &ea_all, 0, &info);
275 	if (err)
276 		goto out;
277 
278 	if (!info)
279 		goto out;
280 
281 	/* Enumerate all xattrs. */
282 	if (!find_ea(ea_all, le32_to_cpu(info->size), name, name_len, &off,
283 		     NULL)) {
284 		err = -ENODATA;
285 		goto out;
286 	}
287 	ea = Add2Ptr(ea_all, off);
288 
289 	len = le16_to_cpu(ea->elength);
290 	if (!buffer) {
291 		err = 0;
292 		goto out;
293 	}
294 
295 	if (len > size) {
296 		err = -ERANGE;
297 		if (required)
298 			*required = len;
299 		goto out;
300 	}
301 
302 	memcpy(buffer, ea->name + ea->name_len + 1, len);
303 	err = 0;
304 
305 out:
306 	kfree(ea_all);
307 	if (!required)
308 		ni_unlock(ni);
309 
310 	return err ? err : len;
311 }
312 
ntfs_set_ea(struct inode * inode,const char * name,size_t name_len,const void * value,size_t val_size,int flags,bool locked,__le16 * ea_size)313 static noinline int ntfs_set_ea(struct inode *inode, const char *name,
314 				size_t name_len, const void *value,
315 				size_t val_size, int flags, bool locked,
316 				__le16 *ea_size)
317 {
318 	struct ntfs_inode *ni = ntfs_i(inode);
319 	struct ntfs_sb_info *sbi = ni->mi.sbi;
320 	int err;
321 	struct EA_INFO ea_info;
322 	const struct EA_INFO *info;
323 	struct EA_FULL *new_ea;
324 	struct EA_FULL *ea_all = NULL;
325 	size_t add, new_pack;
326 	u32 off, size, ea_sz;
327 	__le16 size_pack;
328 	struct ATTRIB *attr;
329 	struct ATTR_LIST_ENTRY *le;
330 	struct mft_inode *mi;
331 	struct runs_tree ea_run;
332 	u64 new_sz;
333 	void *p;
334 
335 	if (!locked)
336 		ni_lock(ni);
337 
338 	run_init(&ea_run);
339 
340 	if (name_len > 255) {
341 		err = -ENAMETOOLONG;
342 		goto out;
343 	}
344 
345 	add = ALIGN(struct_size(ea_all, name, 1 + name_len + val_size), 4);
346 
347 	err = ntfs_read_ea(ni, &ea_all, add, &info);
348 	if (err)
349 		goto out;
350 
351 	if (!info) {
352 		memset(&ea_info, 0, sizeof(ea_info));
353 		size = 0;
354 		size_pack = 0;
355 	} else {
356 		memcpy(&ea_info, info, sizeof(ea_info));
357 		size = le32_to_cpu(ea_info.size);
358 		size_pack = ea_info.size_pack;
359 	}
360 
361 	if (info && find_ea(ea_all, size, name, name_len, &off, &ea_sz)) {
362 		struct EA_FULL *ea;
363 
364 		if (flags & XATTR_CREATE) {
365 			err = -EEXIST;
366 			goto out;
367 		}
368 
369 		ea = Add2Ptr(ea_all, off);
370 
371 		/*
372 		 * Check simple case when we try to insert xattr with the same value
373 		 * e.g. ntfs_save_wsl_perm
374 		 */
375 		if (val_size && le16_to_cpu(ea->elength) == val_size &&
376 		    !memcmp(ea->name + ea->name_len + 1, value, val_size)) {
377 			/* xattr already contains the required value. */
378 			goto out;
379 		}
380 
381 		/* Remove current xattr. */
382 		if (ea->flags & FILE_NEED_EA)
383 			le16_add_cpu(&ea_info.count, -1);
384 
385 		le16_add_cpu(&ea_info.size_pack, 0 - packed_ea_size(ea));
386 
387 		memmove(ea, Add2Ptr(ea, ea_sz), size - off - ea_sz);
388 
389 		size -= ea_sz;
390 		memset(Add2Ptr(ea_all, size), 0, ea_sz);
391 
392 		ea_info.size = cpu_to_le32(size);
393 
394 		if ((flags & XATTR_REPLACE) && !val_size) {
395 			/* Remove xattr. */
396 			goto update_ea;
397 		}
398 	} else {
399 		if (flags & XATTR_REPLACE) {
400 			err = -ENODATA;
401 			goto out;
402 		}
403 
404 		if (!ea_all) {
405 			ea_all = kzalloc(add, GFP_NOFS);
406 			if (!ea_all) {
407 				err = -ENOMEM;
408 				goto out;
409 			}
410 		}
411 	}
412 
413 	/* Append new xattr. */
414 	new_ea = Add2Ptr(ea_all, size);
415 	new_ea->size = cpu_to_le32(add);
416 	new_ea->flags = 0;
417 	new_ea->name_len = name_len;
418 	new_ea->elength = cpu_to_le16(val_size);
419 	memcpy(new_ea->name, name, name_len);
420 	new_ea->name[name_len] = 0;
421 	memcpy(new_ea->name + name_len + 1, value, val_size);
422 	new_pack = le16_to_cpu(ea_info.size_pack) + packed_ea_size(new_ea);
423 	ea_info.size_pack = cpu_to_le16(new_pack);
424 	/* New size of ATTR_EA. */
425 	size += add;
426 	ea_info.size = cpu_to_le32(size);
427 
428 	/*
429 	 * 1. Check ea_info.size_pack for overflow.
430 	 * 2. New attribute size must fit value from $AttrDef
431 	 */
432 	if (new_pack > 0xffff || size > sbi->ea_max_size) {
433 		ntfs_inode_warn(
434 			inode,
435 			"The size of extended attributes must not exceed 64KiB");
436 		err = -EFBIG; // -EINVAL?
437 		goto out;
438 	}
439 
440 update_ea:
441 
442 	if (!info) {
443 		/* Create xattr. */
444 		if (!size) {
445 			err = 0;
446 			goto out;
447 		}
448 
449 		err = ni_insert_resident(ni, sizeof(struct EA_INFO),
450 					 ATTR_EA_INFO, NULL, 0, NULL, NULL,
451 					 NULL);
452 		if (err)
453 			goto out;
454 
455 		err = ni_insert_resident(ni, 0, ATTR_EA, NULL, 0, NULL, NULL,
456 					 NULL);
457 		if (err)
458 			goto out;
459 	}
460 
461 	new_sz = size;
462 	err = attr_set_size(ni, ATTR_EA, NULL, 0, &ea_run, new_sz, &new_sz,
463 			    false, NULL);
464 	if (err)
465 		goto out;
466 
467 	le = NULL;
468 	attr = ni_find_attr(ni, NULL, &le, ATTR_EA_INFO, NULL, 0, NULL, &mi);
469 	if (!attr) {
470 		err = -EINVAL;
471 		goto out;
472 	}
473 
474 	if (!size) {
475 		/* Delete xattr, ATTR_EA_INFO */
476 		ni_remove_attr_le(ni, attr, mi, le);
477 	} else {
478 		p = resident_data_ex(attr, sizeof(struct EA_INFO));
479 		if (!p) {
480 			err = -EINVAL;
481 			goto out;
482 		}
483 		memcpy(p, &ea_info, sizeof(struct EA_INFO));
484 		mi->dirty = true;
485 	}
486 
487 	le = NULL;
488 	attr = ni_find_attr(ni, NULL, &le, ATTR_EA, NULL, 0, NULL, &mi);
489 	if (!attr) {
490 		err = -EINVAL;
491 		goto out;
492 	}
493 
494 	if (!size) {
495 		/* Delete xattr, ATTR_EA */
496 		ni_remove_attr_le(ni, attr, mi, le);
497 	} else if (attr->non_res) {
498 		err = attr_load_runs_range(ni, ATTR_EA, NULL, 0, &ea_run, 0,
499 					   size);
500 		if (err)
501 			goto out;
502 
503 		err = ntfs_sb_write_run(sbi, &ea_run, 0, ea_all, size, 0);
504 		if (err)
505 			goto out;
506 	} else {
507 		p = resident_data_ex(attr, size);
508 		if (!p) {
509 			err = -EINVAL;
510 			goto out;
511 		}
512 		memcpy(p, ea_all, size);
513 		mi->dirty = true;
514 	}
515 
516 	/* Check if we delete the last xattr. */
517 	if (size)
518 		ni->ni_flags |= NI_FLAG_EA;
519 	else
520 		ni->ni_flags &= ~NI_FLAG_EA;
521 
522 	if (ea_info.size_pack != size_pack)
523 		ni->ni_flags |= NI_FLAG_UPDATE_PARENT;
524 	if (ea_size)
525 		*ea_size = ea_info.size_pack;
526 	mark_inode_dirty(&ni->vfs_inode);
527 
528 out:
529 	if (!locked)
530 		ni_unlock(ni);
531 
532 	run_close(&ea_run);
533 	kfree(ea_all);
534 
535 	return err;
536 }
537 
538 #ifdef CONFIG_NTFS3_FS_POSIX_ACL
539 
540 /*
541  * ntfs_get_acl - inode_operations::get_acl
542  */
ntfs_get_acl(struct mnt_idmap * idmap,struct dentry * dentry,int type)543 struct posix_acl *ntfs_get_acl(struct mnt_idmap *idmap, struct dentry *dentry,
544 			       int type)
545 {
546 	struct inode *inode = d_inode(dentry);
547 	struct ntfs_inode *ni = ntfs_i(inode);
548 	const char *name;
549 	size_t name_len;
550 	struct posix_acl *acl;
551 	size_t req;
552 	int err;
553 	void *buf;
554 
555 	/* Allocate PATH_MAX bytes. */
556 	buf = __getname();
557 	if (!buf)
558 		return ERR_PTR(-ENOMEM);
559 
560 	/* Possible values of 'type' was already checked above. */
561 	if (type == ACL_TYPE_ACCESS) {
562 		name = XATTR_NAME_POSIX_ACL_ACCESS;
563 		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
564 	} else {
565 		name = XATTR_NAME_POSIX_ACL_DEFAULT;
566 		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
567 	}
568 
569 	ni_lock(ni);
570 
571 	err = ntfs_get_ea(inode, name, name_len, buf, PATH_MAX, &req);
572 
573 	ni_unlock(ni);
574 
575 	/* Translate extended attribute to acl. */
576 	if (err >= 0) {
577 		acl = posix_acl_from_xattr(&init_user_ns, buf, err);
578 	} else if (err == -ENODATA) {
579 		acl = NULL;
580 	} else {
581 		acl = ERR_PTR(err);
582 	}
583 
584 	if (!IS_ERR(acl))
585 		set_cached_acl(inode, type, acl);
586 
587 	__putname(buf);
588 
589 	return acl;
590 }
591 
ntfs_set_acl_ex(struct mnt_idmap * idmap,struct inode * inode,struct posix_acl * acl,int type,bool init_acl)592 static noinline int ntfs_set_acl_ex(struct mnt_idmap *idmap,
593 				    struct inode *inode, struct posix_acl *acl,
594 				    int type, bool init_acl)
595 {
596 	const char *name;
597 	size_t size, name_len;
598 	void *value;
599 	int err;
600 	int flags;
601 	umode_t mode;
602 
603 	if (S_ISLNK(inode->i_mode))
604 		return -EOPNOTSUPP;
605 
606 	mode = inode->i_mode;
607 	switch (type) {
608 	case ACL_TYPE_ACCESS:
609 		/* Do not change i_mode if we are in init_acl */
610 		if (acl && !init_acl) {
611 			err = posix_acl_update_mode(idmap, inode, &mode, &acl);
612 			if (err)
613 				return err;
614 		}
615 		name = XATTR_NAME_POSIX_ACL_ACCESS;
616 		name_len = sizeof(XATTR_NAME_POSIX_ACL_ACCESS) - 1;
617 		break;
618 
619 	case ACL_TYPE_DEFAULT:
620 		if (!S_ISDIR(inode->i_mode))
621 			return acl ? -EACCES : 0;
622 		name = XATTR_NAME_POSIX_ACL_DEFAULT;
623 		name_len = sizeof(XATTR_NAME_POSIX_ACL_DEFAULT) - 1;
624 		break;
625 
626 	default:
627 		return -EINVAL;
628 	}
629 
630 	if (!acl) {
631 		/* Remove xattr if it can be presented via mode. */
632 		size = 0;
633 		value = NULL;
634 		flags = XATTR_REPLACE;
635 	} else {
636 		size = posix_acl_xattr_size(acl->a_count);
637 		value = kmalloc(size, GFP_NOFS);
638 		if (!value)
639 			return -ENOMEM;
640 		err = posix_acl_to_xattr(&init_user_ns, acl, value, size);
641 		if (err < 0)
642 			goto out;
643 		flags = 0;
644 	}
645 
646 	err = ntfs_set_ea(inode, name, name_len, value, size, flags, 0, NULL);
647 	if (err == -ENODATA && !size)
648 		err = 0; /* Removing non existed xattr. */
649 	if (!err) {
650 		set_cached_acl(inode, type, acl);
651 		inode->i_mode = mode;
652 		inode_set_ctime_current(inode);
653 		mark_inode_dirty(inode);
654 	}
655 
656 out:
657 	kfree(value);
658 
659 	return err;
660 }
661 
662 /*
663  * ntfs_set_acl - inode_operations::set_acl
664  */
ntfs_set_acl(struct mnt_idmap * idmap,struct dentry * dentry,struct posix_acl * acl,int type)665 int ntfs_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
666 		 struct posix_acl *acl, int type)
667 {
668 	return ntfs_set_acl_ex(idmap, d_inode(dentry), acl, type, false);
669 }
670 
671 /*
672  * ntfs_init_acl - Initialize the ACLs of a new inode.
673  *
674  * Called from ntfs_create_inode().
675  */
ntfs_init_acl(struct mnt_idmap * idmap,struct inode * inode,struct inode * dir)676 int ntfs_init_acl(struct mnt_idmap *idmap, struct inode *inode,
677 		  struct inode *dir)
678 {
679 	struct posix_acl *default_acl, *acl;
680 	int err;
681 
682 	err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
683 	if (err)
684 		return err;
685 
686 	if (default_acl) {
687 		err = ntfs_set_acl_ex(idmap, inode, default_acl,
688 				      ACL_TYPE_DEFAULT, true);
689 		posix_acl_release(default_acl);
690 	} else {
691 		inode->i_default_acl = NULL;
692 	}
693 
694 	if (acl) {
695 		if (!err)
696 			err = ntfs_set_acl_ex(idmap, inode, acl,
697 					      ACL_TYPE_ACCESS, true);
698 		posix_acl_release(acl);
699 	} else {
700 		inode->i_acl = NULL;
701 	}
702 
703 	return err;
704 }
705 #endif
706 
707 /*
708  * ntfs_acl_chmod - Helper for ntfs_setattr().
709  */
ntfs_acl_chmod(struct mnt_idmap * idmap,struct dentry * dentry)710 int ntfs_acl_chmod(struct mnt_idmap *idmap, struct dentry *dentry)
711 {
712 	struct inode *inode = d_inode(dentry);
713 	struct super_block *sb = inode->i_sb;
714 
715 	if (!(sb->s_flags & SB_POSIXACL))
716 		return 0;
717 
718 	if (S_ISLNK(inode->i_mode))
719 		return -EOPNOTSUPP;
720 
721 	return posix_acl_chmod(idmap, dentry, inode->i_mode);
722 }
723 
724 /*
725  * ntfs_listxattr - inode_operations::listxattr
726  */
ntfs_listxattr(struct dentry * dentry,char * buffer,size_t size)727 ssize_t ntfs_listxattr(struct dentry *dentry, char *buffer, size_t size)
728 {
729 	struct inode *inode = d_inode(dentry);
730 	struct ntfs_inode *ni = ntfs_i(inode);
731 	ssize_t ret;
732 
733 	if (!(ni->ni_flags & NI_FLAG_EA)) {
734 		/* no xattr in file */
735 		return 0;
736 	}
737 
738 	ni_lock(ni);
739 
740 	ret = ntfs_list_ea(ni, buffer, size);
741 
742 	ni_unlock(ni);
743 
744 	return ret;
745 }
746 
ntfs_getxattr(const struct xattr_handler * handler,struct dentry * de,struct inode * inode,const char * name,void * buffer,size_t size)747 static int ntfs_getxattr(const struct xattr_handler *handler, struct dentry *de,
748 			 struct inode *inode, const char *name, void *buffer,
749 			 size_t size)
750 {
751 	int err;
752 	struct ntfs_inode *ni = ntfs_i(inode);
753 
754 	if (unlikely(ntfs3_forced_shutdown(inode->i_sb)))
755 		return -EIO;
756 
757 	/* Dispatch request. */
758 	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
759 		/* system.dos_attrib */
760 		if (!buffer) {
761 			err = sizeof(u8);
762 		} else if (size < sizeof(u8)) {
763 			err = -ENODATA;
764 		} else {
765 			err = sizeof(u8);
766 			*(u8 *)buffer = le32_to_cpu(ni->std_fa);
767 		}
768 		goto out;
769 	}
770 
771 	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
772 	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
773 		/* system.ntfs_attrib */
774 		if (!buffer) {
775 			err = sizeof(u32);
776 		} else if (size < sizeof(u32)) {
777 			err = -ENODATA;
778 		} else {
779 			err = sizeof(u32);
780 			*(u32 *)buffer = le32_to_cpu(ni->std_fa);
781 			if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
782 				*(__be32 *)buffer = cpu_to_be32(*(u32 *)buffer);
783 		}
784 		goto out;
785 	}
786 
787 	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
788 		/* system.ntfs_security*/
789 		struct SECURITY_DESCRIPTOR_RELATIVE *sd = NULL;
790 		size_t sd_size = 0;
791 
792 		if (!is_ntfs3(ni->mi.sbi)) {
793 			/* We should get nt4 security. */
794 			err = -EINVAL;
795 			goto out;
796 		} else if (le32_to_cpu(ni->std_security_id) <
797 			   SECURITY_ID_FIRST) {
798 			err = -ENOENT;
799 			goto out;
800 		}
801 
802 		err = ntfs_get_security_by_id(ni->mi.sbi, ni->std_security_id,
803 					      &sd, &sd_size);
804 		if (err)
805 			goto out;
806 
807 		if (!is_sd_valid(sd, sd_size)) {
808 			ntfs_inode_warn(
809 				inode,
810 				"looks like you get incorrect security descriptor id=%u",
811 				ni->std_security_id);
812 		}
813 
814 		if (!buffer) {
815 			err = sd_size;
816 		} else if (size < sd_size) {
817 			err = -ENODATA;
818 		} else {
819 			err = sd_size;
820 			memcpy(buffer, sd, sd_size);
821 		}
822 		kfree(sd);
823 		goto out;
824 	}
825 
826 	/* Deal with NTFS extended attribute. */
827 	err = ntfs_get_ea(inode, name, strlen(name), buffer, size, NULL);
828 
829 out:
830 	return err;
831 }
832 
833 /*
834  * ntfs_setxattr - inode_operations::setxattr
835  */
ntfs_setxattr(const struct xattr_handler * handler,struct mnt_idmap * idmap,struct dentry * de,struct inode * inode,const char * name,const void * value,size_t size,int flags)836 static noinline int ntfs_setxattr(const struct xattr_handler *handler,
837 				  struct mnt_idmap *idmap, struct dentry *de,
838 				  struct inode *inode, const char *name,
839 				  const void *value, size_t size, int flags)
840 {
841 	int err = -EINVAL;
842 	struct ntfs_inode *ni = ntfs_i(inode);
843 	enum FILE_ATTRIBUTE new_fa;
844 
845 	/* Dispatch request. */
846 	if (!strcmp(name, SYSTEM_DOS_ATTRIB)) {
847 		if (sizeof(u8) != size)
848 			goto out;
849 		new_fa = cpu_to_le32(*(u8 *)value);
850 		goto set_new_fa;
851 	}
852 
853 	if (!strcmp(name, SYSTEM_NTFS_ATTRIB) ||
854 	    !strcmp(name, SYSTEM_NTFS_ATTRIB_BE)) {
855 		if (size != sizeof(u32))
856 			goto out;
857 		if (!strcmp(name, SYSTEM_NTFS_ATTRIB_BE))
858 			new_fa = cpu_to_le32(be32_to_cpu(*(__be32 *)value));
859 		else
860 			new_fa = cpu_to_le32(*(u32 *)value);
861 
862 		if (S_ISREG(inode->i_mode)) {
863 			/* Process compressed/sparsed in special way. */
864 			ni_lock(ni);
865 			err = ni_new_attr_flags(ni, new_fa);
866 			ni_unlock(ni);
867 			if (err)
868 				goto out;
869 		}
870 set_new_fa:
871 		/*
872 		 * Thanks Mark Harmstone:
873 		 * Keep directory bit consistency.
874 		 */
875 		if (S_ISDIR(inode->i_mode))
876 			new_fa |= FILE_ATTRIBUTE_DIRECTORY;
877 		else
878 			new_fa &= ~FILE_ATTRIBUTE_DIRECTORY;
879 
880 		if (ni->std_fa != new_fa) {
881 			ni->std_fa = new_fa;
882 			if (new_fa & FILE_ATTRIBUTE_READONLY)
883 				inode->i_mode &= ~0222;
884 			else
885 				inode->i_mode |= 0222;
886 			/* Std attribute always in primary record. */
887 			ni->mi.dirty = true;
888 			mark_inode_dirty(inode);
889 		}
890 		err = 0;
891 
892 		goto out;
893 	}
894 
895 	if (!strcmp(name, SYSTEM_NTFS_SECURITY)) {
896 		/* system.ntfs_security*/
897 		__le32 security_id;
898 		bool inserted;
899 		struct ATTR_STD_INFO5 *std;
900 
901 		if (!is_ntfs3(ni->mi.sbi)) {
902 			/*
903 			 * We should replace ATTR_SECURE.
904 			 * Skip this way cause it is nt4 feature.
905 			 */
906 			err = -EINVAL;
907 			goto out;
908 		}
909 
910 		if (!is_sd_valid(value, size)) {
911 			err = -EINVAL;
912 			ntfs_inode_warn(
913 				inode,
914 				"you try to set invalid security descriptor");
915 			goto out;
916 		}
917 
918 		err = ntfs_insert_security(ni->mi.sbi, value, size,
919 					   &security_id, &inserted);
920 		if (err)
921 			goto out;
922 
923 		ni_lock(ni);
924 		std = ni_std5(ni);
925 		if (!std) {
926 			err = -EINVAL;
927 		} else if (std->security_id != security_id) {
928 			std->security_id = ni->std_security_id = security_id;
929 			/* Std attribute always in primary record. */
930 			ni->mi.dirty = true;
931 			mark_inode_dirty(&ni->vfs_inode);
932 		}
933 		ni_unlock(ni);
934 		goto out;
935 	}
936 
937 	/* Deal with NTFS extended attribute. */
938 	err = ntfs_set_ea(inode, name, strlen(name), value, size, flags, 0,
939 			  NULL);
940 
941 out:
942 	inode_set_ctime_current(inode);
943 	mark_inode_dirty(inode);
944 
945 	return err;
946 }
947 
948 /*
949  * ntfs_save_wsl_perm
950  *
951  * save uid/gid/mode in xattr
952  */
ntfs_save_wsl_perm(struct inode * inode,__le16 * ea_size)953 int ntfs_save_wsl_perm(struct inode *inode, __le16 *ea_size)
954 {
955 	int err;
956 	__le32 value;
957 	struct ntfs_inode *ni = ntfs_i(inode);
958 
959 	ni_lock(ni);
960 	value = cpu_to_le32(i_uid_read(inode));
961 	err = ntfs_set_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value,
962 			  sizeof(value), 0, true, ea_size);
963 	if (err)
964 		goto out;
965 
966 	value = cpu_to_le32(i_gid_read(inode));
967 	err = ntfs_set_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value,
968 			  sizeof(value), 0, true, ea_size);
969 	if (err)
970 		goto out;
971 
972 	value = cpu_to_le32(inode->i_mode);
973 	err = ntfs_set_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value,
974 			  sizeof(value), 0, true, ea_size);
975 	if (err)
976 		goto out;
977 
978 	if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) {
979 		value = cpu_to_le32(inode->i_rdev);
980 		err = ntfs_set_ea(inode, "$LXDEV", sizeof("$LXDEV") - 1, &value,
981 				  sizeof(value), 0, true, ea_size);
982 		if (err)
983 			goto out;
984 	}
985 
986 out:
987 	ni_unlock(ni);
988 	/* In case of error should we delete all WSL xattr? */
989 	return err;
990 }
991 
992 /*
993  * ntfs_get_wsl_perm
994  *
995  * get uid/gid/mode from xattr
996  * it is called from ntfs_iget5->ntfs_read_mft
997  */
ntfs_get_wsl_perm(struct inode * inode)998 void ntfs_get_wsl_perm(struct inode *inode)
999 {
1000 	size_t sz;
1001 	__le32 value[3];
1002 
1003 	if (ntfs_get_ea(inode, "$LXUID", sizeof("$LXUID") - 1, &value[0],
1004 			sizeof(value[0]), &sz) == sizeof(value[0]) &&
1005 	    ntfs_get_ea(inode, "$LXGID", sizeof("$LXGID") - 1, &value[1],
1006 			sizeof(value[1]), &sz) == sizeof(value[1]) &&
1007 	    ntfs_get_ea(inode, "$LXMOD", sizeof("$LXMOD") - 1, &value[2],
1008 			sizeof(value[2]), &sz) == sizeof(value[2])) {
1009 		i_uid_write(inode, (uid_t)le32_to_cpu(value[0]));
1010 		i_gid_write(inode, (gid_t)le32_to_cpu(value[1]));
1011 		inode->i_mode = le32_to_cpu(value[2]);
1012 
1013 		if (ntfs_get_ea(inode, "$LXDEV", sizeof("$$LXDEV") - 1,
1014 				&value[0], sizeof(value),
1015 				&sz) == sizeof(value[0])) {
1016 			inode->i_rdev = le32_to_cpu(value[0]);
1017 		}
1018 	}
1019 }
1020 
ntfs_xattr_user_list(struct dentry * dentry)1021 static bool ntfs_xattr_user_list(struct dentry *dentry)
1022 {
1023 	return true;
1024 }
1025 
1026 // clang-format off
1027 static const struct xattr_handler ntfs_other_xattr_handler = {
1028 	.prefix	= "",
1029 	.get	= ntfs_getxattr,
1030 	.set	= ntfs_setxattr,
1031 	.list	= ntfs_xattr_user_list,
1032 };
1033 
1034 const struct xattr_handler * const ntfs_xattr_handlers[] = {
1035 	&ntfs_other_xattr_handler,
1036 	NULL,
1037 };
1038 // clang-format on
1039