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1 /*
2  * This file is part of UBIFS.
3  *
4  * Copyright (C) 2006-2008 Nokia Corporation.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published by
8  * the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program; if not, write to the Free Software Foundation, Inc., 51
17  * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18  *
19  * Authors: Artem Bityutskiy (Битюцкий Артём)
20  *          Adrian Hunter
21  */
22 
23 /*
24  * This file implements UBIFS extended attributes support.
25  *
26  * Extended attributes are implemented as regular inodes with attached data,
27  * which limits extended attribute size to UBIFS block size (4KiB). Names of
28  * extended attributes are described by extended attribute entries (xentries),
29  * which are almost identical to directory entries, but have different key type.
30  *
31  * In other words, the situation with extended attributes is very similar to
32  * directories. Indeed, any inode (but of course not xattr inodes) may have a
33  * number of associated xentries, just like directory inodes have associated
34  * directory entries. Extended attribute entries store the name of the extended
35  * attribute, the host inode number, and the extended attribute inode number.
36  * Similarly, direntries store the name, the parent and the target inode
37  * numbers. Thus, most of the common UBIFS mechanisms may be re-used for
38  * extended attributes.
39  *
40  * The number of extended attributes is not limited, but there is Linux
41  * limitation on the maximum possible size of the list of all extended
42  * attributes associated with an inode (%XATTR_LIST_MAX), so UBIFS makes sure
43  * the sum of all extended attribute names of the inode does not exceed that
44  * limit.
45  *
46  * Extended attributes are synchronous, which means they are written to the
47  * flash media synchronously and there is no write-back for extended attribute
48  * inodes. The extended attribute values are not stored in compressed form on
49  * the media.
50  *
51  * Since extended attributes are represented by regular inodes, they are cached
52  * in the VFS inode cache. The xentries are cached in the LNC cache (see
53  * tnc.c).
54  *
55  * ACL support is not implemented.
56  */
57 
58 #include "ubifs.h"
59 #include <linux/fs.h>
60 #include <linux/slab.h>
61 #include <linux/xattr.h>
62 
63 /*
64  * Limit the number of extended attributes per inode so that the total size
65  * (@xattr_size) is guaranteeded to fit in an 'unsigned int'.
66  */
67 #define MAX_XATTRS_PER_INODE 65535
68 
69 /*
70  * Extended attribute type constants.
71  *
72  * USER_XATTR: user extended attribute ("user.*")
73  * TRUSTED_XATTR: trusted extended attribute ("trusted.*)
74  * SECURITY_XATTR: security extended attribute ("security.*")
75  */
76 enum {
77 	USER_XATTR,
78 	TRUSTED_XATTR,
79 	SECURITY_XATTR,
80 };
81 
82 static const struct inode_operations empty_iops;
83 static const struct file_operations empty_fops;
84 
85 /**
86  * create_xattr - create an extended attribute.
87  * @c: UBIFS file-system description object
88  * @host: host inode
89  * @nm: extended attribute name
90  * @value: extended attribute value
91  * @size: size of extended attribute value
92  *
93  * This is a helper function which creates an extended attribute of name @nm
94  * and value @value for inode @host. The host inode is also updated on flash
95  * because the ctime and extended attribute accounting data changes. This
96  * function returns zero in case of success and a negative error code in case
97  * of failure.
98  */
create_xattr(struct ubifs_info * c,struct inode * host,const struct qstr * nm,const void * value,int size)99 static int create_xattr(struct ubifs_info *c, struct inode *host,
100 			const struct qstr *nm, const void *value, int size)
101 {
102 	int err, names_len;
103 	struct inode *inode;
104 	struct ubifs_inode *ui, *host_ui = ubifs_inode(host);
105 	struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1,
106 				.new_ino_d = ALIGN(size, 8), .dirtied_ino = 1,
107 				.dirtied_ino_d = ALIGN(host_ui->data_len, 8) };
108 
109 	if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE) {
110 		ubifs_err(c, "inode %lu already has too many xattrs (%d), cannot create more",
111 			  host->i_ino, host_ui->xattr_cnt);
112 		return -ENOSPC;
113 	}
114 	/*
115 	 * Linux limits the maximum size of the extended attribute names list
116 	 * to %XATTR_LIST_MAX. This means we should not allow creating more
117 	 * extended attributes if the name list becomes larger. This limitation
118 	 * is artificial for UBIFS, though.
119 	 */
120 	names_len = host_ui->xattr_names + host_ui->xattr_cnt + nm->len + 1;
121 	if (names_len > XATTR_LIST_MAX) {
122 		ubifs_err(c, "cannot add one more xattr name to inode %lu, total names length would become %d, max. is %d",
123 			  host->i_ino, names_len, XATTR_LIST_MAX);
124 		return -ENOSPC;
125 	}
126 
127 	err = ubifs_budget_space(c, &req);
128 	if (err)
129 		return err;
130 
131 	inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO);
132 	if (IS_ERR(inode)) {
133 		err = PTR_ERR(inode);
134 		goto out_budg;
135 	}
136 
137 	/* Re-define all operations to be "nothing" */
138 	inode->i_mapping->a_ops = &empty_aops;
139 	inode->i_op = &empty_iops;
140 	inode->i_fop = &empty_fops;
141 
142 	inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME | S_NOQUOTA;
143 	ui = ubifs_inode(inode);
144 	ui->xattr = 1;
145 	ui->flags |= UBIFS_XATTR_FL;
146 	ui->data = kmemdup(value, size, GFP_NOFS);
147 	if (!ui->data) {
148 		err = -ENOMEM;
149 		goto out_free;
150 	}
151 	inode->i_size = ui->ui_size = size;
152 	ui->data_len = size;
153 
154 	mutex_lock(&host_ui->ui_mutex);
155 	host->i_ctime = ubifs_current_time(host);
156 	host_ui->xattr_cnt += 1;
157 	host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
158 	host_ui->xattr_size += CALC_XATTR_BYTES(size);
159 	host_ui->xattr_names += nm->len;
160 
161 	err = ubifs_jnl_update(c, host, nm, inode, 0, 1);
162 	if (err)
163 		goto out_cancel;
164 	mutex_unlock(&host_ui->ui_mutex);
165 
166 	ubifs_release_budget(c, &req);
167 	insert_inode_hash(inode);
168 	iput(inode);
169 	return 0;
170 
171 out_cancel:
172 	host_ui->xattr_cnt -= 1;
173 	host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
174 	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
175 	host_ui->xattr_names -= nm->len;
176 	mutex_unlock(&host_ui->ui_mutex);
177 out_free:
178 	make_bad_inode(inode);
179 	iput(inode);
180 out_budg:
181 	ubifs_release_budget(c, &req);
182 	return err;
183 }
184 
185 /**
186  * change_xattr - change an extended attribute.
187  * @c: UBIFS file-system description object
188  * @host: host inode
189  * @inode: extended attribute inode
190  * @value: extended attribute value
191  * @size: size of extended attribute value
192  *
193  * This helper function changes the value of extended attribute @inode with new
194  * data from @value. Returns zero in case of success and a negative error code
195  * in case of failure.
196  */
change_xattr(struct ubifs_info * c,struct inode * host,struct inode * inode,const void * value,int size)197 static int change_xattr(struct ubifs_info *c, struct inode *host,
198 			struct inode *inode, const void *value, int size)
199 {
200 	int err;
201 	struct ubifs_inode *host_ui = ubifs_inode(host);
202 	struct ubifs_inode *ui = ubifs_inode(inode);
203 	void *buf = NULL;
204 	int old_size;
205 	struct ubifs_budget_req req = { .dirtied_ino = 2,
206 		.dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) };
207 
208 	ubifs_assert(ui->data_len == inode->i_size);
209 	err = ubifs_budget_space(c, &req);
210 	if (err)
211 		return err;
212 
213 	buf = kmemdup(value, size, GFP_NOFS);
214 	if (!buf) {
215 		err = -ENOMEM;
216 		goto out_free;
217 	}
218 	mutex_lock(&ui->ui_mutex);
219 	kfree(ui->data);
220 	ui->data = buf;
221 	inode->i_size = ui->ui_size = size;
222 	old_size = ui->data_len;
223 	ui->data_len = size;
224 	mutex_unlock(&ui->ui_mutex);
225 
226 	mutex_lock(&host_ui->ui_mutex);
227 	host->i_ctime = ubifs_current_time(host);
228 	host_ui->xattr_size -= CALC_XATTR_BYTES(old_size);
229 	host_ui->xattr_size += CALC_XATTR_BYTES(size);
230 
231 	/*
232 	 * It is important to write the host inode after the xattr inode
233 	 * because if the host inode gets synchronized (via 'fsync()'), then
234 	 * the extended attribute inode gets synchronized, because it goes
235 	 * before the host inode in the write-buffer.
236 	 */
237 	err = ubifs_jnl_change_xattr(c, inode, host);
238 	if (err)
239 		goto out_cancel;
240 	mutex_unlock(&host_ui->ui_mutex);
241 
242 	ubifs_release_budget(c, &req);
243 	return 0;
244 
245 out_cancel:
246 	host_ui->xattr_size -= CALC_XATTR_BYTES(size);
247 	host_ui->xattr_size += CALC_XATTR_BYTES(old_size);
248 	mutex_unlock(&host_ui->ui_mutex);
249 	make_bad_inode(inode);
250 out_free:
251 	ubifs_release_budget(c, &req);
252 	return err;
253 }
254 
iget_xattr(struct ubifs_info * c,ino_t inum)255 static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
256 {
257 	struct inode *inode;
258 
259 	inode = ubifs_iget(c->vfs_sb, inum);
260 	if (IS_ERR(inode)) {
261 		ubifs_err(c, "dead extended attribute entry, error %d",
262 			  (int)PTR_ERR(inode));
263 		return inode;
264 	}
265 	if (ubifs_inode(inode)->xattr)
266 		return inode;
267 	ubifs_err(c, "corrupt extended attribute entry");
268 	iput(inode);
269 	return ERR_PTR(-EINVAL);
270 }
271 
__ubifs_setxattr(struct inode * host,const char * name,const void * value,size_t size,int flags,bool check_lock)272 static int __ubifs_setxattr(struct inode *host, const char *name,
273 			    const void *value, size_t size, int flags,
274 			    bool check_lock)
275 {
276 	struct inode *inode;
277 	struct ubifs_info *c = host->i_sb->s_fs_info;
278 	struct qstr nm = QSTR_INIT(name, strlen(name));
279 	struct ubifs_dent_node *xent;
280 	union ubifs_key key;
281 	int err;
282 
283 	if (check_lock)
284 		ubifs_assert(inode_is_locked(host));
285 
286 	if (size > UBIFS_MAX_INO_DATA)
287 		return -ERANGE;
288 
289 	if (nm.len > UBIFS_MAX_NLEN)
290 		return -ENAMETOOLONG;
291 
292 	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
293 	if (!xent)
294 		return -ENOMEM;
295 
296 	/*
297 	 * The extended attribute entries are stored in LNC, so multiple
298 	 * look-ups do not involve reading the flash.
299 	 */
300 	xent_key_init(c, &key, host->i_ino, &nm);
301 	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
302 	if (err) {
303 		if (err != -ENOENT)
304 			goto out_free;
305 
306 		if (flags & XATTR_REPLACE)
307 			/* We are asked not to create the xattr */
308 			err = -ENODATA;
309 		else
310 			err = create_xattr(c, host, &nm, value, size);
311 		goto out_free;
312 	}
313 
314 	if (flags & XATTR_CREATE) {
315 		/* We are asked not to replace the xattr */
316 		err = -EEXIST;
317 		goto out_free;
318 	}
319 
320 	inode = iget_xattr(c, le64_to_cpu(xent->inum));
321 	if (IS_ERR(inode)) {
322 		err = PTR_ERR(inode);
323 		goto out_free;
324 	}
325 
326 	err = change_xattr(c, host, inode, value, size);
327 	iput(inode);
328 
329 out_free:
330 	kfree(xent);
331 	return err;
332 }
333 
__ubifs_getxattr(struct inode * host,const char * name,void * buf,size_t size)334 static ssize_t __ubifs_getxattr(struct inode *host, const char *name,
335 				void *buf, size_t size)
336 {
337 	struct inode *inode;
338 	struct ubifs_info *c = host->i_sb->s_fs_info;
339 	struct qstr nm = QSTR_INIT(name, strlen(name));
340 	struct ubifs_inode *ui;
341 	struct ubifs_dent_node *xent;
342 	union ubifs_key key;
343 	int err;
344 
345 	if (nm.len > UBIFS_MAX_NLEN)
346 		return -ENAMETOOLONG;
347 
348 	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
349 	if (!xent)
350 		return -ENOMEM;
351 
352 	xent_key_init(c, &key, host->i_ino, &nm);
353 	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
354 	if (err) {
355 		if (err == -ENOENT)
356 			err = -ENODATA;
357 		goto out_unlock;
358 	}
359 
360 	inode = iget_xattr(c, le64_to_cpu(xent->inum));
361 	if (IS_ERR(inode)) {
362 		err = PTR_ERR(inode);
363 		goto out_unlock;
364 	}
365 
366 	ui = ubifs_inode(inode);
367 	ubifs_assert(inode->i_size == ui->data_len);
368 	ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
369 
370 	mutex_lock(&ui->ui_mutex);
371 	if (buf) {
372 		/* If @buf is %NULL we are supposed to return the length */
373 		if (ui->data_len > size) {
374 			ubifs_err(c, "buffer size %zd, xattr len %d",
375 				  size, ui->data_len);
376 			err = -ERANGE;
377 			goto out_iput;
378 		}
379 
380 		memcpy(buf, ui->data, ui->data_len);
381 	}
382 	err = ui->data_len;
383 
384 out_iput:
385 	mutex_unlock(&ui->ui_mutex);
386 	iput(inode);
387 out_unlock:
388 	kfree(xent);
389 	return err;
390 }
391 
ubifs_listxattr(struct dentry * dentry,char * buffer,size_t size)392 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
393 {
394 	union ubifs_key key;
395 	struct inode *host = d_inode(dentry);
396 	struct ubifs_info *c = host->i_sb->s_fs_info;
397 	struct ubifs_inode *host_ui = ubifs_inode(host);
398 	struct ubifs_dent_node *xent, *pxent = NULL;
399 	int err, len, written = 0;
400 	struct qstr nm = { .name = NULL };
401 
402 	dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino,
403 		dentry, size);
404 
405 	len = host_ui->xattr_names + host_ui->xattr_cnt;
406 	if (!buffer)
407 		/*
408 		 * We should return the minimum buffer size which will fit a
409 		 * null-terminated list of all the extended attribute names.
410 		 */
411 		return len;
412 
413 	if (len > size)
414 		return -ERANGE;
415 
416 	lowest_xent_key(c, &key, host->i_ino);
417 	while (1) {
418 		xent = ubifs_tnc_next_ent(c, &key, &nm);
419 		if (IS_ERR(xent)) {
420 			err = PTR_ERR(xent);
421 			break;
422 		}
423 
424 		nm.name = xent->name;
425 		nm.len = le16_to_cpu(xent->nlen);
426 
427 		/* Show trusted namespace only for "power" users */
428 		if (strncmp(xent->name, XATTR_TRUSTED_PREFIX,
429 			    XATTR_TRUSTED_PREFIX_LEN) ||
430 		    capable(CAP_SYS_ADMIN)) {
431 			memcpy(buffer + written, nm.name, nm.len + 1);
432 			written += nm.len + 1;
433 		}
434 
435 		kfree(pxent);
436 		pxent = xent;
437 		key_read(c, &xent->key, &key);
438 	}
439 
440 	kfree(pxent);
441 	if (err != -ENOENT) {
442 		ubifs_err(c, "cannot find next direntry, error %d", err);
443 		return err;
444 	}
445 
446 	ubifs_assert(written <= size);
447 	return written;
448 }
449 
remove_xattr(struct ubifs_info * c,struct inode * host,struct inode * inode,const struct qstr * nm)450 static int remove_xattr(struct ubifs_info *c, struct inode *host,
451 			struct inode *inode, const struct qstr *nm)
452 {
453 	int err;
454 	struct ubifs_inode *host_ui = ubifs_inode(host);
455 	struct ubifs_inode *ui = ubifs_inode(inode);
456 	struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1,
457 				.dirtied_ino_d = ALIGN(host_ui->data_len, 8) };
458 
459 	ubifs_assert(ui->data_len == inode->i_size);
460 
461 	err = ubifs_budget_space(c, &req);
462 	if (err)
463 		return err;
464 
465 	mutex_lock(&host_ui->ui_mutex);
466 	host->i_ctime = ubifs_current_time(host);
467 	host_ui->xattr_cnt -= 1;
468 	host_ui->xattr_size -= CALC_DENT_SIZE(nm->len);
469 	host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
470 	host_ui->xattr_names -= nm->len;
471 
472 	err = ubifs_jnl_delete_xattr(c, host, inode, nm);
473 	if (err)
474 		goto out_cancel;
475 	mutex_unlock(&host_ui->ui_mutex);
476 
477 	ubifs_release_budget(c, &req);
478 	return 0;
479 
480 out_cancel:
481 	host_ui->xattr_cnt += 1;
482 	host_ui->xattr_size += CALC_DENT_SIZE(nm->len);
483 	host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
484 	host_ui->xattr_names += nm->len;
485 	mutex_unlock(&host_ui->ui_mutex);
486 	ubifs_release_budget(c, &req);
487 	make_bad_inode(inode);
488 	return err;
489 }
490 
__ubifs_removexattr(struct inode * host,const char * name)491 static int __ubifs_removexattr(struct inode *host, const char *name)
492 {
493 	struct inode *inode;
494 	struct ubifs_info *c = host->i_sb->s_fs_info;
495 	struct qstr nm = QSTR_INIT(name, strlen(name));
496 	struct ubifs_dent_node *xent;
497 	union ubifs_key key;
498 	int err;
499 
500 	ubifs_assert(inode_is_locked(host));
501 
502 	if (nm.len > UBIFS_MAX_NLEN)
503 		return -ENAMETOOLONG;
504 
505 	xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
506 	if (!xent)
507 		return -ENOMEM;
508 
509 	xent_key_init(c, &key, host->i_ino, &nm);
510 	err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
511 	if (err) {
512 		if (err == -ENOENT)
513 			err = -ENODATA;
514 		goto out_free;
515 	}
516 
517 	inode = iget_xattr(c, le64_to_cpu(xent->inum));
518 	if (IS_ERR(inode)) {
519 		err = PTR_ERR(inode);
520 		goto out_free;
521 	}
522 
523 	ubifs_assert(inode->i_nlink == 1);
524 	clear_nlink(inode);
525 	err = remove_xattr(c, host, inode, &nm);
526 	if (err)
527 		set_nlink(inode, 1);
528 
529 	/* If @i_nlink is 0, 'iput()' will delete the inode */
530 	iput(inode);
531 
532 out_free:
533 	kfree(xent);
534 	return err;
535 }
536 
init_xattrs(struct inode * inode,const struct xattr * xattr_array,void * fs_info)537 static int init_xattrs(struct inode *inode, const struct xattr *xattr_array,
538 		      void *fs_info)
539 {
540 	const struct xattr *xattr;
541 	char *name;
542 	int err = 0;
543 
544 	for (xattr = xattr_array; xattr->name != NULL; xattr++) {
545 		name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
546 			       strlen(xattr->name) + 1, GFP_NOFS);
547 		if (!name) {
548 			err = -ENOMEM;
549 			break;
550 		}
551 		strcpy(name, XATTR_SECURITY_PREFIX);
552 		strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
553 		err = __ubifs_setxattr(inode, name, xattr->value,
554 				       xattr->value_len, 0, false);
555 		kfree(name);
556 		if (err < 0)
557 			break;
558 	}
559 
560 	return err;
561 }
562 
ubifs_init_security(struct inode * dentry,struct inode * inode,const struct qstr * qstr)563 int ubifs_init_security(struct inode *dentry, struct inode *inode,
564 			const struct qstr *qstr)
565 {
566 	int err;
567 
568 	err = security_inode_init_security(inode, dentry, qstr,
569 					   &init_xattrs, 0);
570 	if (err) {
571 		struct ubifs_info *c = dentry->i_sb->s_fs_info;
572 		ubifs_err(c, "cannot initialize security for inode %lu, error %d",
573 			  inode->i_ino, err);
574 	}
575 	return err;
576 }
577 
ubifs_xattr_get(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,void * buffer,size_t size)578 static int ubifs_xattr_get(const struct xattr_handler *handler,
579 			   struct dentry *dentry, struct inode *inode,
580 			   const char *name, void *buffer, size_t size)
581 {
582 	dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name,
583 		inode->i_ino, dentry, size);
584 
585 	name = xattr_full_name(handler, name);
586 	return __ubifs_getxattr(inode, name, buffer, size);
587 }
588 
ubifs_xattr_set(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,const void * value,size_t size,int flags)589 static int ubifs_xattr_set(const struct xattr_handler *handler,
590 			   struct dentry *dentry, struct inode *inode,
591 			   const char *name, const void *value,
592 			   size_t size, int flags)
593 {
594 	dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd",
595 		name, inode->i_ino, dentry, size);
596 
597 	name = xattr_full_name(handler, name);
598 
599 	if (value)
600 		return __ubifs_setxattr(inode, name, value, size, flags,
601 					true);
602 	else
603 		return __ubifs_removexattr(inode, name);
604 }
605 
606 static const struct xattr_handler ubifs_user_xattr_handler = {
607 	.prefix = XATTR_USER_PREFIX,
608 	.get = ubifs_xattr_get,
609 	.set = ubifs_xattr_set,
610 };
611 
612 static const struct xattr_handler ubifs_trusted_xattr_handler = {
613 	.prefix = XATTR_TRUSTED_PREFIX,
614 	.get = ubifs_xattr_get,
615 	.set = ubifs_xattr_set,
616 };
617 
618 static const struct xattr_handler ubifs_security_xattr_handler = {
619 	.prefix = XATTR_SECURITY_PREFIX,
620 	.get = ubifs_xattr_get,
621 	.set = ubifs_xattr_set,
622 };
623 
624 const struct xattr_handler *ubifs_xattr_handlers[] = {
625 	&ubifs_user_xattr_handler,
626 	&ubifs_trusted_xattr_handler,
627 	&ubifs_security_xattr_handler,
628 	NULL
629 };
630