fs/ubifs/xattr.c

   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  */
  99 static int create_xattr(struct ubifs_info *c, struct inode *host,
 100                         const struct fscrypt_name *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 + fname_len(nm) + 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(fname_len(nm));
 158         host_ui->xattr_size += CALC_XATTR_BYTES(size);
 159         host_ui->xattr_names += fname_len(nm);
 160
 161         /*
 162          * We handle UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT here because we
 163          * have to set the UBIFS_CRYPT_FL flag on the host inode.
 164          * To avoid multiple updates of the same inode in the same operation,
 165          * let's do it here.
 166          */
 167         if (strcmp(fname_name(nm), UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) == 0)
 168                 host_ui->flags |= UBIFS_CRYPT_FL;
 169
 170         err = ubifs_jnl_update(c, host, nm, inode, 0, 1);
 171         if (err)
 172                 goto out_cancel;
 173         mutex_unlock(&host_ui->ui_mutex);
 174
 175         ubifs_release_budget(c, &req);
 176         insert_inode_hash(inode);
 177         iput(inode);
 178         return 0;
 179
 180 out_cancel:
 181         host_ui->xattr_cnt -= 1;
 182         host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm));
 183         host_ui->xattr_size -= CALC_XATTR_BYTES(size);
 184         host_ui->xattr_names -= fname_len(nm);
 185         host_ui->flags &= ~UBIFS_CRYPT_FL;
 186         mutex_unlock(&host_ui->ui_mutex);
 187 out_free:
 188         make_bad_inode(inode);
 189         iput(inode);
 190 out_budg:
 191         ubifs_release_budget(c, &req);
 192         return err;
 193 }
 194
 195 /**
 196  * change_xattr - change an extended attribute.
 197  * @c: UBIFS file-system description object
 198  * @host: host inode
 199  * @inode: extended attribute inode
 200  * @value: extended attribute value
 201  * @size: size of extended attribute value
 202  *
 203  * This helper function changes the value of extended attribute @inode with new
 204  * data from @value. Returns zero in case of success and a negative error code
 205  * in case of failure.
 206  */
 207 static int change_xattr(struct ubifs_info *c, struct inode *host,
 208                         struct inode *inode, const void *value, int size)
 209 {
 210         int err;
 211         struct ubifs_inode *host_ui = ubifs_inode(host);
 212         struct ubifs_inode *ui = ubifs_inode(inode);
 213         void *buf = NULL;
 214         int old_size;
 215         struct ubifs_budget_req req = { .dirtied_ino = 2,
 216                 .dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) };
 217
 218         ubifs_assert(ui->data_len == inode->i_size);
 219         err = ubifs_budget_space(c, &req);
 220         if (err)
 221                 return err;
 222
 223         buf = kmemdup(value, size, GFP_NOFS);
 224         if (!buf) {
 225                 err = -ENOMEM;
 226                 goto out_free;
 227         }
 228         mutex_lock(&ui->ui_mutex);
 229         kfree(ui->data);
 230         ui->data = buf;
 231         inode->i_size = ui->ui_size = size;
 232         old_size = ui->data_len;
 233         ui->data_len = size;
 234         mutex_unlock(&ui->ui_mutex);
 235
 236         mutex_lock(&host_ui->ui_mutex);
 237         host->i_ctime = ubifs_current_time(host);
 238         host_ui->xattr_size -= CALC_XATTR_BYTES(old_size);
 239         host_ui->xattr_size += CALC_XATTR_BYTES(size);
 240
 241         /*
 242          * It is important to write the host inode after the xattr inode
 243          * because if the host inode gets synchronized (via 'fsync()'), then
 244          * the extended attribute inode gets synchronized, because it goes
 245          * before the host inode in the write-buffer.
 246          */
 247         err = ubifs_jnl_change_xattr(c, inode, host);
 248         if (err)
 249                 goto out_cancel;
 250         mutex_unlock(&host_ui->ui_mutex);
 251
 252         ubifs_release_budget(c, &req);
 253         return 0;
 254
 255 out_cancel:
 256         host_ui->xattr_size -= CALC_XATTR_BYTES(size);
 257         host_ui->xattr_size += CALC_XATTR_BYTES(old_size);
 258         mutex_unlock(&host_ui->ui_mutex);
 259         make_bad_inode(inode);
 260 out_free:
 261         ubifs_release_budget(c, &req);
 262         return err;
 263 }
 264
 265 static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum)
 266 {
 267         struct inode *inode;
 268
 269         inode = ubifs_iget(c->vfs_sb, inum);
 270         if (IS_ERR(inode)) {
 271                 ubifs_err(c, "dead extended attribute entry, error %d",
 272                           (int)PTR_ERR(inode));
 273                 return inode;
 274         }
 275         if (ubifs_inode(inode)->xattr)
 276                 return inode;
 277         ubifs_err(c, "corrupt extended attribute entry");
 278         iput(inode);
 279         return ERR_PTR(-EINVAL);
 280 }
 281
 282 int ubifs_xattr_set(struct inode *host, const char *name, const void *value,
 283                     size_t size, int flags)
 284 {
 285         struct inode *inode;
 286         struct ubifs_info *c = host->i_sb->s_fs_info;
 287         struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))};
 288         struct ubifs_dent_node *xent;
 289         union ubifs_key key;
 290         int err;
 291
 292         /*
 293          * Creating an encryption context is done unlocked since we
 294          * operate on a new inode which is not visible to other users
 295          * at this point.
 296          */
 297         if (strcmp(name, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) != 0)
 298                 ubifs_assert(inode_is_locked(host));
 299
 300         if (size > UBIFS_MAX_INO_DATA)
 301                 return -ERANGE;
 302
 303         if (fname_len(&nm) > UBIFS_MAX_NLEN)
 304                 return -ENAMETOOLONG;
 305
 306         xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
 307         if (!xent)
 308                 return -ENOMEM;
 309
 310         /*
 311          * The extended attribute entries are stored in LNC, so multiple
 312          * look-ups do not involve reading the flash.
 313          */
 314         xent_key_init(c, &key, host->i_ino, &nm);
 315         err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
 316         if (err) {
 317                 if (err != -ENOENT)
 318                         goto out_free;
 319
 320                 if (flags & XATTR_REPLACE)
 321                         /* We are asked not to create the xattr */
 322                         err = -ENODATA;
 323                 else
 324                         err = create_xattr(c, host, &nm, value, size);
 325                 goto out_free;
 326         }
 327
 328         if (flags & XATTR_CREATE) {
 329                 /* We are asked not to replace the xattr */
 330                 err = -EEXIST;
 331                 goto out_free;
 332         }
 333
 334         inode = iget_xattr(c, le64_to_cpu(xent->inum));
 335         if (IS_ERR(inode)) {
 336                 err = PTR_ERR(inode);
 337                 goto out_free;
 338         }
 339
 340         err = change_xattr(c, host, inode, value, size);
 341         iput(inode);
 342
 343 out_free:
 344         kfree(xent);
 345         return err;
 346 }
 347
 348 ssize_t ubifs_xattr_get(struct inode *host, const char *name, void *buf,
 349                         size_t size)
 350 {
 351         struct inode *inode;
 352         struct ubifs_info *c = host->i_sb->s_fs_info;
 353         struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))};
 354         struct ubifs_inode *ui;
 355         struct ubifs_dent_node *xent;
 356         union ubifs_key key;
 357         int err;
 358
 359         if (fname_len(&nm) > UBIFS_MAX_NLEN)
 360                 return -ENAMETOOLONG;
 361
 362         xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
 363         if (!xent)
 364                 return -ENOMEM;
 365
 366         xent_key_init(c, &key, host->i_ino, &nm);
 367         err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
 368         if (err) {
 369                 if (err == -ENOENT)
 370                         err = -ENODATA;
 371                 goto out_unlock;
 372         }
 373
 374         inode = iget_xattr(c, le64_to_cpu(xent->inum));
 375         if (IS_ERR(inode)) {
 376                 err = PTR_ERR(inode);
 377                 goto out_unlock;
 378         }
 379
 380         ui = ubifs_inode(inode);
 381         ubifs_assert(inode->i_size == ui->data_len);
 382         ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len);
 383
 384         mutex_lock(&ui->ui_mutex);
 385         if (buf) {
 386                 /* If @buf is %NULL we are supposed to return the length */
 387                 if (ui->data_len > size) {
 388                         ubifs_err(c, "buffer size %zd, xattr len %d",
 389                                   size, ui->data_len);
 390                         err = -ERANGE;
 391                         goto out_iput;
 392                 }
 393
 394                 memcpy(buf, ui->data, ui->data_len);
 395         }
 396         err = ui->data_len;
 397
 398 out_iput:
 399         mutex_unlock(&ui->ui_mutex);
 400         iput(inode);
 401 out_unlock:
 402         kfree(xent);
 403         return err;
 404 }
 405
 406 static bool xattr_visible(const char *name)
 407 {
 408         /* File encryption related xattrs are for internal use only */
 409         if (strcmp(name, UBIFS_XATTR_NAME_ENCRYPTION_CONTEXT) == 0)
 410                 return false;
 411
 412         /* Show trusted namespace only for "power" users */
 413         if (strncmp(name, XATTR_TRUSTED_PREFIX,
 414                     XATTR_TRUSTED_PREFIX_LEN) == 0 && !capable(CAP_SYS_ADMIN))
 415                 return false;
 416
 417         return true;
 418 }
 419
 420 ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size)
 421 {
 422         union ubifs_key key;
 423         struct inode *host = d_inode(dentry);
 424         struct ubifs_info *c = host->i_sb->s_fs_info;
 425         struct ubifs_inode *host_ui = ubifs_inode(host);
 426         struct ubifs_dent_node *xent, *pxent = NULL;
 427         int err, len, written = 0;
 428         struct fscrypt_name nm = {0};
 429
 430         dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino,
 431                 dentry, size);
 432
 433         len = host_ui->xattr_names + host_ui->xattr_cnt;
 434         if (!buffer)
 435                 /*
 436                  * We should return the minimum buffer size which will fit a
 437                  * null-terminated list of all the extended attribute names.
 438                  */
 439                 return len;
 440
 441         if (len > size)
 442                 return -ERANGE;
 443
 444         lowest_xent_key(c, &key, host->i_ino);
 445         while (1) {
 446                 xent = ubifs_tnc_next_ent(c, &key, &nm);
 447                 if (IS_ERR(xent)) {
 448                         err = PTR_ERR(xent);
 449                         break;
 450                 }
 451
 452                 fname_name(&nm) = xent->name;
 453                 fname_len(&nm) = le16_to_cpu(xent->nlen);
 454
 455                 if (xattr_visible(xent->name)) {
 456                         memcpy(buffer + written, fname_name(&nm), fname_len(&nm) + 1);
 457                         written += fname_len(&nm) + 1;
 458                 }
 459
 460                 kfree(pxent);
 461                 pxent = xent;
 462                 key_read(c, &xent->key, &key);
 463         }
 464
 465         kfree(pxent);
 466         if (err != -ENOENT) {
 467                 ubifs_err(c, "cannot find next direntry, error %d", err);
 468                 return err;
 469         }
 470
 471         ubifs_assert(written <= size);
 472         return written;
 473 }
 474
 475 static int remove_xattr(struct ubifs_info *c, struct inode *host,
 476                         struct inode *inode, const struct fscrypt_name *nm)
 477 {
 478         int err;
 479         struct ubifs_inode *host_ui = ubifs_inode(host);
 480         struct ubifs_inode *ui = ubifs_inode(inode);
 481         struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1,
 482                                 .dirtied_ino_d = ALIGN(host_ui->data_len, 8) };
 483
 484         ubifs_assert(ui->data_len == inode->i_size);
 485
 486         err = ubifs_budget_space(c, &req);
 487         if (err)
 488                 return err;
 489
 490         mutex_lock(&host_ui->ui_mutex);
 491         host->i_ctime = ubifs_current_time(host);
 492         host_ui->xattr_cnt -= 1;
 493         host_ui->xattr_size -= CALC_DENT_SIZE(fname_len(nm));
 494         host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len);
 495         host_ui->xattr_names -= fname_len(nm);
 496
 497         err = ubifs_jnl_delete_xattr(c, host, inode, nm);
 498         if (err)
 499                 goto out_cancel;
 500         mutex_unlock(&host_ui->ui_mutex);
 501
 502         ubifs_release_budget(c, &req);
 503         return 0;
 504
 505 out_cancel:
 506         host_ui->xattr_cnt += 1;
 507         host_ui->xattr_size += CALC_DENT_SIZE(fname_len(nm));
 508         host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len);
 509         host_ui->xattr_names += fname_len(nm);
 510         mutex_unlock(&host_ui->ui_mutex);
 511         ubifs_release_budget(c, &req);
 512         make_bad_inode(inode);
 513         return err;
 514 }
 515
 516 static int ubifs_xattr_remove(struct inode *host, const char *name)
 517 {
 518         struct inode *inode;
 519         struct ubifs_info *c = host->i_sb->s_fs_info;
 520         struct fscrypt_name nm = { .disk_name = FSTR_INIT((char *)name, strlen(name))};
 521         struct ubifs_dent_node *xent;
 522         union ubifs_key key;
 523         int err;
 524
 525         ubifs_assert(inode_is_locked(host));
 526
 527         if (fname_len(&nm) > UBIFS_MAX_NLEN)
 528                 return -ENAMETOOLONG;
 529
 530         xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS);
 531         if (!xent)
 532                 return -ENOMEM;
 533
 534         xent_key_init(c, &key, host->i_ino, &nm);
 535         err = ubifs_tnc_lookup_nm(c, &key, xent, &nm);
 536         if (err) {
 537                 if (err == -ENOENT)
 538                         err = -ENODATA;
 539                 goto out_free;
 540         }
 541
 542         inode = iget_xattr(c, le64_to_cpu(xent->inum));
 543         if (IS_ERR(inode)) {
 544                 err = PTR_ERR(inode);
 545                 goto out_free;
 546         }
 547
 548         ubifs_assert(inode->i_nlink == 1);
 549         clear_nlink(inode);
 550         err = remove_xattr(c, host, inode, &nm);
 551         if (err)
 552                 set_nlink(inode, 1);
 553
 554         /* If @i_nlink is 0, 'iput()' will delete the inode */
 555         iput(inode);
 556
 557 out_free:
 558         kfree(xent);
 559         return err;
 560 }
 561
 562 static int init_xattrs(struct inode *inode, const struct xattr *xattr_array,
 563                       void *fs_info)
 564 {
 565         const struct xattr *xattr;
 566         char *name;
 567         int err = 0;
 568
 569         for (xattr = xattr_array; xattr->name != NULL; xattr++) {
 570                 name = kmalloc(XATTR_SECURITY_PREFIX_LEN +
 571                                strlen(xattr->name) + 1, GFP_NOFS);
 572                 if (!name) {
 573                         err = -ENOMEM;
 574                         break;
 575                 }
 576                 strcpy(name, XATTR_SECURITY_PREFIX);
 577                 strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name);
 578                 err = ubifs_xattr_set(inode, name, xattr->value,
 579                                       xattr->value_len, 0);
 580                 kfree(name);
 581                 if (err < 0)
 582                         break;
 583         }
 584
 585         return err;
 586 }
 587
 588 int ubifs_init_security(struct inode *dentry, struct inode *inode,
 589                         const struct qstr *qstr)
 590 {
 591         int err;
 592
 593         err = security_inode_init_security(inode, dentry, qstr,
 594                                            &init_xattrs, 0);
 595         if (err) {
 596                 struct ubifs_info *c = dentry->i_sb->s_fs_info;
 597                 ubifs_err(c, "cannot initialize security for inode %lu, error %d",
 598                           inode->i_ino, err);
 599         }
 600         return err;
 601 }
 602
 603 static int xattr_get(const struct xattr_handler *handler,
 604                            struct dentry *dentry, struct inode *inode,
 605                            const char *name, void *buffer, size_t size)
 606 {
 607         dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name,
 608                 inode->i_ino, dentry, size);
 609
 610         name = xattr_full_name(handler, name);
 611         return ubifs_xattr_get(inode, name, buffer, size);
 612 }
 613
 614 static int xattr_set(const struct xattr_handler *handler,
 615                            struct dentry *dentry, struct inode *inode,
 616                            const char *name, const void *value,
 617                            size_t size, int flags)
 618 {
 619         dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd",
 620                 name, inode->i_ino, dentry, size);
 621
 622         name = xattr_full_name(handler, name);
 623
 624         if (value)
 625                 return ubifs_xattr_set(inode, name, value, size, flags);
 626         else
 627                 return ubifs_xattr_remove(inode, name);
 628 }
 629
 630 static const struct xattr_handler ubifs_user_xattr_handler = {
 631         .prefix = XATTR_USER_PREFIX,
 632         .get = xattr_get,
 633         .set = xattr_set,
 634 };
 635
 636 static const struct xattr_handler ubifs_trusted_xattr_handler = {
 637         .prefix = XATTR_TRUSTED_PREFIX,
 638         .get = xattr_get,
 639         .set = xattr_set,
 640 };
 641
 642 static const struct xattr_handler ubifs_security_xattr_handler = {
 643         .prefix = XATTR_SECURITY_PREFIX,
 644         .get = xattr_get,
 645         .set = xattr_set,
 646 };
 647
 648 const struct xattr_handler *ubifs_xattr_handlers[] = {
 649         &ubifs_user_xattr_handler,
 650         &ubifs_trusted_xattr_handler,
 651         &ubifs_security_xattr_handler,
 652         NULL
 653 };