fs/ecryptfs/inode.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /**
   3  * eCryptfs: Linux filesystem encryption layer
   4  *
   5  * Copyright (C) 1997-2004 Erez Zadok
   6  * Copyright (C) 2001-2004 Stony Brook University
   7  * Copyright (C) 2004-2007 International Business Machines Corp.
   8  *   Author(s): Michael A. Halcrow <mahalcro@us.ibm.com>
   9  *              Michael C. Thompsion <mcthomps@us.ibm.com>
  10  */
  11
  12 #include <linux/file.h>
  13 #include <linux/vmalloc.h>
  14 #include <linux/pagemap.h>
  15 #include <linux/dcache.h>
  16 #include <linux/namei.h>
  17 #include <linux/mount.h>
  18 #include <linux/fs_stack.h>
  19 #include <linux/slab.h>
  20 #include <linux/xattr.h>
  21 #include <asm/unaligned.h>
  22 #include "ecryptfs_kernel.h"
  23
  24 static struct dentry *lock_parent(struct dentry *dentry)
  25 {
  26         struct dentry *dir;
  27
  28         dir = dget_parent(dentry);
  29         inode_lock_nested(d_inode(dir), I_MUTEX_PARENT);
  30         return dir;
  31 }
  32
  33 static void unlock_dir(struct dentry *dir)
  34 {
  35         inode_unlock(d_inode(dir));
  36         dput(dir);
  37 }
  38
  39 static int ecryptfs_inode_test(struct inode *inode, void *lower_inode)
  40 {
  41         return ecryptfs_inode_to_lower(inode) == lower_inode;
  42 }
  43
  44 static int ecryptfs_inode_set(struct inode *inode, void *opaque)
  45 {
  46         struct inode *lower_inode = opaque;
  47
  48         ecryptfs_set_inode_lower(inode, lower_inode);
  49         fsstack_copy_attr_all(inode, lower_inode);
  50         /* i_size will be overwritten for encrypted regular files */
  51         fsstack_copy_inode_size(inode, lower_inode);
  52         inode->i_ino = lower_inode->i_ino;
  53         inode->i_mapping->a_ops = &ecryptfs_aops;
  54
  55         if (S_ISLNK(inode->i_mode))
  56                 inode->i_op = &ecryptfs_symlink_iops;
  57         else if (S_ISDIR(inode->i_mode))
  58                 inode->i_op = &ecryptfs_dir_iops;
  59         else
  60                 inode->i_op = &ecryptfs_main_iops;
  61
  62         if (S_ISDIR(inode->i_mode))
  63                 inode->i_fop = &ecryptfs_dir_fops;
  64         else if (special_file(inode->i_mode))
  65                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
  66         else
  67                 inode->i_fop = &ecryptfs_main_fops;
  68
  69         return 0;
  70 }
  71
  72 static struct inode *__ecryptfs_get_inode(struct inode *lower_inode,
  73                                           struct super_block *sb)
  74 {
  75         struct inode *inode;
  76
  77         if (lower_inode->i_sb != ecryptfs_superblock_to_lower(sb))
  78                 return ERR_PTR(-EXDEV);
  79         if (!igrab(lower_inode))
  80                 return ERR_PTR(-ESTALE);
  81         inode = iget5_locked(sb, (unsigned long)lower_inode,
  82                              ecryptfs_inode_test, ecryptfs_inode_set,
  83                              lower_inode);
  84         if (!inode) {
  85                 iput(lower_inode);
  86                 return ERR_PTR(-EACCES);
  87         }
  88         if (!(inode->i_state & I_NEW))
  89                 iput(lower_inode);
  90
  91         return inode;
  92 }
  93
  94 struct inode *ecryptfs_get_inode(struct inode *lower_inode,
  95                                  struct super_block *sb)
  96 {
  97         struct inode *inode = __ecryptfs_get_inode(lower_inode, sb);
  98
  99         if (!IS_ERR(inode) && (inode->i_state & I_NEW))
 100                 unlock_new_inode(inode);
 101
 102         return inode;
 103 }
 104
 105 /**
 106  * ecryptfs_interpose
 107  * @lower_dentry: Existing dentry in the lower filesystem
 108  * @dentry: ecryptfs' dentry
 109  * @sb: ecryptfs's super_block
 110  *
 111  * Interposes upper and lower dentries.
 112  *
 113  * Returns zero on success; non-zero otherwise
 114  */
 115 static int ecryptfs_interpose(struct dentry *lower_dentry,
 116                               struct dentry *dentry, struct super_block *sb)
 117 {
 118         struct inode *inode = ecryptfs_get_inode(d_inode(lower_dentry), sb);
 119
 120         if (IS_ERR(inode))
 121                 return PTR_ERR(inode);
 122         d_instantiate(dentry, inode);
 123
 124         return 0;
 125 }
 126
 127 static int ecryptfs_do_unlink(struct inode *dir, struct dentry *dentry,
 128                               struct inode *inode)
 129 {
 130         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 131         struct dentry *lower_dir_dentry;
 132         struct inode *lower_dir_inode;
 133         int rc;
 134
 135         lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
 136         lower_dir_inode = d_inode(lower_dir_dentry);
 137         inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT);
 138         dget(lower_dentry);     // don't even try to make the lower negative
 139         if (lower_dentry->d_parent != lower_dir_dentry)
 140                 rc = -EINVAL;
 141         else if (d_unhashed(lower_dentry))
 142                 rc = -EINVAL;
 143         else
 144                 rc = vfs_unlink(&init_user_ns, lower_dir_inode, lower_dentry,
 145                                 NULL);
 146         if (rc) {
 147                 printk(KERN_ERR "Error in vfs_unlink; rc = [%d]\n", rc);
 148                 goto out_unlock;
 149         }
 150         fsstack_copy_attr_times(dir, lower_dir_inode);
 151         set_nlink(inode, ecryptfs_inode_to_lower(inode)->i_nlink);
 152         inode->i_ctime = dir->i_ctime;
 153 out_unlock:
 154         dput(lower_dentry);
 155         inode_unlock(lower_dir_inode);
 156         if (!rc)
 157                 d_drop(dentry);
 158         return rc;
 159 }
 160
 161 /**
 162  * ecryptfs_do_create
 163  * @directory_inode: inode of the new file's dentry's parent in ecryptfs
 164  * @ecryptfs_dentry: New file's dentry in ecryptfs
 165  * @mode: The mode of the new file
 166  *
 167  * Creates the underlying file and the eCryptfs inode which will link to
 168  * it. It will also update the eCryptfs directory inode to mimic the
 169  * stat of the lower directory inode.
 170  *
 171  * Returns the new eCryptfs inode on success; an ERR_PTR on error condition
 172  */
 173 static struct inode *
 174 ecryptfs_do_create(struct inode *directory_inode,
 175                    struct dentry *ecryptfs_dentry, umode_t mode)
 176 {
 177         int rc;
 178         struct dentry *lower_dentry;
 179         struct dentry *lower_dir_dentry;
 180         struct inode *inode;
 181
 182         lower_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry);
 183         lower_dir_dentry = lock_parent(lower_dentry);
 184         rc = vfs_create(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
 185                         mode, true);
 186         if (rc) {
 187                 printk(KERN_ERR "%s: Failure to create dentry in lower fs; "
 188                        "rc = [%d]\n", __func__, rc);
 189                 inode = ERR_PTR(rc);
 190                 goto out_lock;
 191         }
 192         inode = __ecryptfs_get_inode(d_inode(lower_dentry),
 193                                      directory_inode->i_sb);
 194         if (IS_ERR(inode)) {
 195                 vfs_unlink(&init_user_ns, d_inode(lower_dir_dentry),
 196                            lower_dentry, NULL);
 197                 goto out_lock;
 198         }
 199         fsstack_copy_attr_times(directory_inode, d_inode(lower_dir_dentry));
 200         fsstack_copy_inode_size(directory_inode, d_inode(lower_dir_dentry));
 201 out_lock:
 202         unlock_dir(lower_dir_dentry);
 203         return inode;
 204 }
 205
 206 /**
 207  * ecryptfs_initialize_file
 208  *
 209  * Cause the file to be changed from a basic empty file to an ecryptfs
 210  * file with a header and first data page.
 211  *
 212  * Returns zero on success
 213  */
 214 int ecryptfs_initialize_file(struct dentry *ecryptfs_dentry,
 215                              struct inode *ecryptfs_inode)
 216 {
 217         struct ecryptfs_crypt_stat *crypt_stat =
 218                 &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
 219         int rc = 0;
 220
 221         if (S_ISDIR(ecryptfs_inode->i_mode)) {
 222                 ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
 223                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 224                 goto out;
 225         }
 226         ecryptfs_printk(KERN_DEBUG, "Initializing crypto context\n");
 227         rc = ecryptfs_new_file_context(ecryptfs_inode);
 228         if (rc) {
 229                 ecryptfs_printk(KERN_ERR, "Error creating new file "
 230                                 "context; rc = [%d]\n", rc);
 231                 goto out;
 232         }
 233         rc = ecryptfs_get_lower_file(ecryptfs_dentry, ecryptfs_inode);
 234         if (rc) {
 235                 printk(KERN_ERR "%s: Error attempting to initialize "
 236                         "the lower file for the dentry with name "
 237                         "[%pd]; rc = [%d]\n", __func__,
 238                         ecryptfs_dentry, rc);
 239                 goto out;
 240         }
 241         rc = ecryptfs_write_metadata(ecryptfs_dentry, ecryptfs_inode);
 242         if (rc)
 243                 printk(KERN_ERR "Error writing headers; rc = [%d]\n", rc);
 244         ecryptfs_put_lower_file(ecryptfs_inode);
 245 out:
 246         return rc;
 247 }
 248
 249 /**
 250  * ecryptfs_create
 251  * @dir: The inode of the directory in which to create the file.
 252  * @dentry: The eCryptfs dentry
 253  * @mode: The mode of the new file.
 254  *
 255  * Creates a new file.
 256  *
 257  * Returns zero on success; non-zero on error condition
 258  */
 259 static int
 260 ecryptfs_create(struct user_namespace *mnt_userns,
 261                 struct inode *directory_inode, struct dentry *ecryptfs_dentry,
 262                 umode_t mode, bool excl)
 263 {
 264         struct inode *ecryptfs_inode;
 265         int rc;
 266
 267         ecryptfs_inode = ecryptfs_do_create(directory_inode, ecryptfs_dentry,
 268                                             mode);
 269         if (IS_ERR(ecryptfs_inode)) {
 270                 ecryptfs_printk(KERN_WARNING, "Failed to create file in"
 271                                 "lower filesystem\n");
 272                 rc = PTR_ERR(ecryptfs_inode);
 273                 goto out;
 274         }
 275         /* At this point, a file exists on "disk"; we need to make sure
 276          * that this on disk file is prepared to be an ecryptfs file */
 277         rc = ecryptfs_initialize_file(ecryptfs_dentry, ecryptfs_inode);
 278         if (rc) {
 279                 ecryptfs_do_unlink(directory_inode, ecryptfs_dentry,
 280                                    ecryptfs_inode);
 281                 iget_failed(ecryptfs_inode);
 282                 goto out;
 283         }
 284         d_instantiate_new(ecryptfs_dentry, ecryptfs_inode);
 285 out:
 286         return rc;
 287 }
 288
 289 static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
 290 {
 291         struct ecryptfs_crypt_stat *crypt_stat;
 292         int rc;
 293
 294         rc = ecryptfs_get_lower_file(dentry, inode);
 295         if (rc) {
 296                 printk(KERN_ERR "%s: Error attempting to initialize "
 297                         "the lower file for the dentry with name "
 298                         "[%pd]; rc = [%d]\n", __func__,
 299                         dentry, rc);
 300                 return rc;
 301         }
 302
 303         crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
 304         /* TODO: lock for crypt_stat comparison */
 305         if (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED))
 306                 ecryptfs_set_default_sizes(crypt_stat);
 307
 308         rc = ecryptfs_read_and_validate_header_region(inode);
 309         ecryptfs_put_lower_file(inode);
 310         if (rc) {
 311                 rc = ecryptfs_read_and_validate_xattr_region(dentry, inode);
 312                 if (!rc)
 313                         crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
 314         }
 315
 316         /* Must return 0 to allow non-eCryptfs files to be looked up, too */
 317         return 0;
 318 }
 319
 320 /**
 321  * ecryptfs_lookup_interpose - Dentry interposition for a lookup
 322  */
 323 static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry,
 324                                      struct dentry *lower_dentry)
 325 {
 326         struct path *path = ecryptfs_dentry_to_lower_path(dentry->d_parent);
 327         struct inode *inode, *lower_inode;
 328         struct ecryptfs_dentry_info *dentry_info;
 329         int rc = 0;
 330
 331         dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
 332         if (!dentry_info) {
 333                 dput(lower_dentry);
 334                 return ERR_PTR(-ENOMEM);
 335         }
 336
 337         fsstack_copy_attr_atime(d_inode(dentry->d_parent),
 338                                 d_inode(path->dentry));
 339         BUG_ON(!d_count(lower_dentry));
 340
 341         ecryptfs_set_dentry_private(dentry, dentry_info);
 342         dentry_info->lower_path.mnt = mntget(path->mnt);
 343         dentry_info->lower_path.dentry = lower_dentry;
 344
 345         /*
 346          * negative dentry can go positive under us here - its parent is not
 347          * locked.  That's OK and that could happen just as we return from
 348          * ecryptfs_lookup() anyway.  Just need to be careful and fetch
 349          * ->d_inode only once - it's not stable here.
 350          */
 351         lower_inode = READ_ONCE(lower_dentry->d_inode);
 352
 353         if (!lower_inode) {
 354                 /* We want to add because we couldn't find in lower */
 355                 d_add(dentry, NULL);
 356                 return NULL;
 357         }
 358         inode = __ecryptfs_get_inode(lower_inode, dentry->d_sb);
 359         if (IS_ERR(inode)) {
 360                 printk(KERN_ERR "%s: Error interposing; rc = [%ld]\n",
 361                        __func__, PTR_ERR(inode));
 362                 return ERR_CAST(inode);
 363         }
 364         if (S_ISREG(inode->i_mode)) {
 365                 rc = ecryptfs_i_size_read(dentry, inode);
 366                 if (rc) {
 367                         make_bad_inode(inode);
 368                         return ERR_PTR(rc);
 369                 }
 370         }
 371
 372         if (inode->i_state & I_NEW)
 373                 unlock_new_inode(inode);
 374         return d_splice_alias(inode, dentry);
 375 }
 376
 377 /**
 378  * ecryptfs_lookup
 379  * @ecryptfs_dir_inode: The eCryptfs directory inode
 380  * @ecryptfs_dentry: The eCryptfs dentry that we are looking up
 381  * @flags: lookup flags
 382  *
 383  * Find a file on disk. If the file does not exist, then we'll add it to the
 384  * dentry cache and continue on to read it from the disk.
 385  */
 386 static struct dentry *ecryptfs_lookup(struct inode *ecryptfs_dir_inode,
 387                                       struct dentry *ecryptfs_dentry,
 388                                       unsigned int flags)
 389 {
 390         char *encrypted_and_encoded_name = NULL;
 391         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 392         struct dentry *lower_dir_dentry, *lower_dentry;
 393         const char *name = ecryptfs_dentry->d_name.name;
 394         size_t len = ecryptfs_dentry->d_name.len;
 395         struct dentry *res;
 396         int rc = 0;
 397
 398         lower_dir_dentry = ecryptfs_dentry_to_lower(ecryptfs_dentry->d_parent);
 399
 400         mount_crypt_stat = &ecryptfs_superblock_to_private(
 401                                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
 402         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
 403                 rc = ecryptfs_encrypt_and_encode_filename(
 404                         &encrypted_and_encoded_name, &len,
 405                         mount_crypt_stat, name, len);
 406                 if (rc) {
 407                         printk(KERN_ERR "%s: Error attempting to encrypt and encode "
 408                                "filename; rc = [%d]\n", __func__, rc);
 409                         return ERR_PTR(rc);
 410                 }
 411                 name = encrypted_and_encoded_name;
 412         }
 413
 414         lower_dentry = lookup_one_len_unlocked(name, lower_dir_dentry, len);
 415         if (IS_ERR(lower_dentry)) {
 416                 ecryptfs_printk(KERN_DEBUG, "%s: lookup_one_len() returned "
 417                                 "[%ld] on lower_dentry = [%s]\n", __func__,
 418                                 PTR_ERR(lower_dentry),
 419                                 name);
 420                 res = ERR_CAST(lower_dentry);
 421         } else {
 422                 res = ecryptfs_lookup_interpose(ecryptfs_dentry, lower_dentry);
 423         }
 424         kfree(encrypted_and_encoded_name);
 425         return res;
 426 }
 427
 428 static int ecryptfs_link(struct dentry *old_dentry, struct inode *dir,
 429                          struct dentry *new_dentry)
 430 {
 431         struct dentry *lower_old_dentry;
 432         struct dentry *lower_new_dentry;
 433         struct dentry *lower_dir_dentry;
 434         u64 file_size_save;
 435         int rc;
 436
 437         file_size_save = i_size_read(d_inode(old_dentry));
 438         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 439         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 440         dget(lower_old_dentry);
 441         dget(lower_new_dentry);
 442         lower_dir_dentry = lock_parent(lower_new_dentry);
 443         rc = vfs_link(lower_old_dentry, &init_user_ns,
 444                       d_inode(lower_dir_dentry), lower_new_dentry, NULL);
 445         if (rc || d_really_is_negative(lower_new_dentry))
 446                 goto out_lock;
 447         rc = ecryptfs_interpose(lower_new_dentry, new_dentry, dir->i_sb);
 448         if (rc)
 449                 goto out_lock;
 450         fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
 451         fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
 452         set_nlink(d_inode(old_dentry),
 453                   ecryptfs_inode_to_lower(d_inode(old_dentry))->i_nlink);
 454         i_size_write(d_inode(new_dentry), file_size_save);
 455 out_lock:
 456         unlock_dir(lower_dir_dentry);
 457         dput(lower_new_dentry);
 458         dput(lower_old_dentry);
 459         return rc;
 460 }
 461
 462 static int ecryptfs_unlink(struct inode *dir, struct dentry *dentry)
 463 {
 464         return ecryptfs_do_unlink(dir, dentry, d_inode(dentry));
 465 }
 466
 467 static int ecryptfs_symlink(struct user_namespace *mnt_userns,
 468                             struct inode *dir, struct dentry *dentry,
 469                             const char *symname)
 470 {
 471         int rc;
 472         struct dentry *lower_dentry;
 473         struct dentry *lower_dir_dentry;
 474         char *encoded_symname;
 475         size_t encoded_symlen;
 476         struct ecryptfs_mount_crypt_stat *mount_crypt_stat = NULL;
 477
 478         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 479         dget(lower_dentry);
 480         lower_dir_dentry = lock_parent(lower_dentry);
 481         mount_crypt_stat = &ecryptfs_superblock_to_private(
 482                 dir->i_sb)->mount_crypt_stat;
 483         rc = ecryptfs_encrypt_and_encode_filename(&encoded_symname,
 484                                                   &encoded_symlen,
 485                                                   mount_crypt_stat, symname,
 486                                                   strlen(symname));
 487         if (rc)
 488                 goto out_lock;
 489         rc = vfs_symlink(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
 490                          encoded_symname);
 491         kfree(encoded_symname);
 492         if (rc || d_really_is_negative(lower_dentry))
 493                 goto out_lock;
 494         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
 495         if (rc)
 496                 goto out_lock;
 497         fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
 498         fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
 499 out_lock:
 500         unlock_dir(lower_dir_dentry);
 501         dput(lower_dentry);
 502         if (d_really_is_negative(dentry))
 503                 d_drop(dentry);
 504         return rc;
 505 }
 506
 507 static int ecryptfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 508                           struct dentry *dentry, umode_t mode)
 509 {
 510         int rc;
 511         struct dentry *lower_dentry;
 512         struct dentry *lower_dir_dentry;
 513
 514         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 515         lower_dir_dentry = lock_parent(lower_dentry);
 516         rc = vfs_mkdir(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
 517                        mode);
 518         if (rc || d_really_is_negative(lower_dentry))
 519                 goto out;
 520         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
 521         if (rc)
 522                 goto out;
 523         fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
 524         fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
 525         set_nlink(dir, d_inode(lower_dir_dentry)->i_nlink);
 526 out:
 527         unlock_dir(lower_dir_dentry);
 528         if (d_really_is_negative(dentry))
 529                 d_drop(dentry);
 530         return rc;
 531 }
 532
 533 static int ecryptfs_rmdir(struct inode *dir, struct dentry *dentry)
 534 {
 535         struct dentry *lower_dentry;
 536         struct dentry *lower_dir_dentry;
 537         struct inode *lower_dir_inode;
 538         int rc;
 539
 540         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 541         lower_dir_dentry = ecryptfs_dentry_to_lower(dentry->d_parent);
 542         lower_dir_inode = d_inode(lower_dir_dentry);
 543
 544         inode_lock_nested(lower_dir_inode, I_MUTEX_PARENT);
 545         dget(lower_dentry);     // don't even try to make the lower negative
 546         if (lower_dentry->d_parent != lower_dir_dentry)
 547                 rc = -EINVAL;
 548         else if (d_unhashed(lower_dentry))
 549                 rc = -EINVAL;
 550         else
 551                 rc = vfs_rmdir(&init_user_ns, lower_dir_inode, lower_dentry);
 552         if (!rc) {
 553                 clear_nlink(d_inode(dentry));
 554                 fsstack_copy_attr_times(dir, lower_dir_inode);
 555                 set_nlink(dir, lower_dir_inode->i_nlink);
 556         }
 557         dput(lower_dentry);
 558         inode_unlock(lower_dir_inode);
 559         if (!rc)
 560                 d_drop(dentry);
 561         return rc;
 562 }
 563
 564 static int
 565 ecryptfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
 566                struct dentry *dentry, umode_t mode, dev_t dev)
 567 {
 568         int rc;
 569         struct dentry *lower_dentry;
 570         struct dentry *lower_dir_dentry;
 571
 572         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 573         lower_dir_dentry = lock_parent(lower_dentry);
 574         rc = vfs_mknod(&init_user_ns, d_inode(lower_dir_dentry), lower_dentry,
 575                        mode, dev);
 576         if (rc || d_really_is_negative(lower_dentry))
 577                 goto out;
 578         rc = ecryptfs_interpose(lower_dentry, dentry, dir->i_sb);
 579         if (rc)
 580                 goto out;
 581         fsstack_copy_attr_times(dir, d_inode(lower_dir_dentry));
 582         fsstack_copy_inode_size(dir, d_inode(lower_dir_dentry));
 583 out:
 584         unlock_dir(lower_dir_dentry);
 585         if (d_really_is_negative(dentry))
 586                 d_drop(dentry);
 587         return rc;
 588 }
 589
 590 static int
 591 ecryptfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir,
 592                 struct dentry *old_dentry, struct inode *new_dir,
 593                 struct dentry *new_dentry, unsigned int flags)
 594 {
 595         int rc;
 596         struct dentry *lower_old_dentry;
 597         struct dentry *lower_new_dentry;
 598         struct dentry *lower_old_dir_dentry;
 599         struct dentry *lower_new_dir_dentry;
 600         struct dentry *trap;
 601         struct inode *target_inode;
 602         struct renamedata rd = {};
 603
 604         if (flags)
 605                 return -EINVAL;
 606
 607         lower_old_dir_dentry = ecryptfs_dentry_to_lower(old_dentry->d_parent);
 608         lower_new_dir_dentry = ecryptfs_dentry_to_lower(new_dentry->d_parent);
 609
 610         lower_old_dentry = ecryptfs_dentry_to_lower(old_dentry);
 611         lower_new_dentry = ecryptfs_dentry_to_lower(new_dentry);
 612
 613         target_inode = d_inode(new_dentry);
 614
 615         trap = lock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 616         dget(lower_new_dentry);
 617         rc = -EINVAL;
 618         if (lower_old_dentry->d_parent != lower_old_dir_dentry)
 619                 goto out_lock;
 620         if (lower_new_dentry->d_parent != lower_new_dir_dentry)
 621                 goto out_lock;
 622         if (d_unhashed(lower_old_dentry) || d_unhashed(lower_new_dentry))
 623                 goto out_lock;
 624         /* source should not be ancestor of target */
 625         if (trap == lower_old_dentry)
 626                 goto out_lock;
 627         /* target should not be ancestor of source */
 628         if (trap == lower_new_dentry) {
 629                 rc = -ENOTEMPTY;
 630                 goto out_lock;
 631         }
 632
 633         rd.old_mnt_userns       = &init_user_ns;
 634         rd.old_dir              = d_inode(lower_old_dir_dentry);
 635         rd.old_dentry           = lower_old_dentry;
 636         rd.new_mnt_userns       = &init_user_ns;
 637         rd.new_dir              = d_inode(lower_new_dir_dentry);
 638         rd.new_dentry           = lower_new_dentry;
 639         rc = vfs_rename(&rd);
 640         if (rc)
 641                 goto out_lock;
 642         if (target_inode)
 643                 fsstack_copy_attr_all(target_inode,
 644                                       ecryptfs_inode_to_lower(target_inode));
 645         fsstack_copy_attr_all(new_dir, d_inode(lower_new_dir_dentry));
 646         if (new_dir != old_dir)
 647                 fsstack_copy_attr_all(old_dir, d_inode(lower_old_dir_dentry));
 648 out_lock:
 649         dput(lower_new_dentry);
 650         unlock_rename(lower_old_dir_dentry, lower_new_dir_dentry);
 651         return rc;
 652 }
 653
 654 static char *ecryptfs_readlink_lower(struct dentry *dentry, size_t *bufsiz)
 655 {
 656         DEFINE_DELAYED_CALL(done);
 657         struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 658         const char *link;
 659         char *buf;
 660         int rc;
 661
 662         link = vfs_get_link(lower_dentry, &done);
 663         if (IS_ERR(link))
 664                 return ERR_CAST(link);
 665
 666         rc = ecryptfs_decode_and_decrypt_filename(&buf, bufsiz, dentry->d_sb,
 667                                                   link, strlen(link));
 668         do_delayed_call(&done);
 669         if (rc)
 670                 return ERR_PTR(rc);
 671
 672         return buf;
 673 }
 674
 675 static const char *ecryptfs_get_link(struct dentry *dentry,
 676                                      struct inode *inode,
 677                                      struct delayed_call *done)
 678 {
 679         size_t len;
 680         char *buf;
 681
 682         if (!dentry)
 683                 return ERR_PTR(-ECHILD);
 684
 685         buf = ecryptfs_readlink_lower(dentry, &len);
 686         if (IS_ERR(buf))
 687                 return buf;
 688         fsstack_copy_attr_atime(d_inode(dentry),
 689                                 d_inode(ecryptfs_dentry_to_lower(dentry)));
 690         buf[len] = '\0';
 691         set_delayed_call(done, kfree_link, buf);
 692         return buf;
 693 }
 694
 695 /**
 696  * upper_size_to_lower_size
 697  * @crypt_stat: Crypt_stat associated with file
 698  * @upper_size: Size of the upper file
 699  *
 700  * Calculate the required size of the lower file based on the
 701  * specified size of the upper file. This calculation is based on the
 702  * number of headers in the underlying file and the extent size.
 703  *
 704  * Returns Calculated size of the lower file.
 705  */
 706 static loff_t
 707 upper_size_to_lower_size(struct ecryptfs_crypt_stat *crypt_stat,
 708                          loff_t upper_size)
 709 {
 710         loff_t lower_size;
 711
 712         lower_size = ecryptfs_lower_header_size(crypt_stat);
 713         if (upper_size != 0) {
 714                 loff_t num_extents;
 715
 716                 num_extents = upper_size >> crypt_stat->extent_shift;
 717                 if (upper_size & ~crypt_stat->extent_mask)
 718                         num_extents++;
 719                 lower_size += (num_extents * crypt_stat->extent_size);
 720         }
 721         return lower_size;
 722 }
 723
 724 /**
 725  * truncate_upper
 726  * @dentry: The ecryptfs layer dentry
 727  * @ia: Address of the ecryptfs inode's attributes
 728  * @lower_ia: Address of the lower inode's attributes
 729  *
 730  * Function to handle truncations modifying the size of the file. Note
 731  * that the file sizes are interpolated. When expanding, we are simply
 732  * writing strings of 0's out. When truncating, we truncate the upper
 733  * inode and update the lower_ia according to the page index
 734  * interpolations. If ATTR_SIZE is set in lower_ia->ia_valid upon return,
 735  * the caller must use lower_ia in a call to notify_change() to perform
 736  * the truncation of the lower inode.
 737  *
 738  * Returns zero on success; non-zero otherwise
 739  */
 740 static int truncate_upper(struct dentry *dentry, struct iattr *ia,
 741                           struct iattr *lower_ia)
 742 {
 743         int rc = 0;
 744         struct inode *inode = d_inode(dentry);
 745         struct ecryptfs_crypt_stat *crypt_stat;
 746         loff_t i_size = i_size_read(inode);
 747         loff_t lower_size_before_truncate;
 748         loff_t lower_size_after_truncate;
 749
 750         if (unlikely((ia->ia_size == i_size))) {
 751                 lower_ia->ia_valid &= ~ATTR_SIZE;
 752                 return 0;
 753         }
 754         rc = ecryptfs_get_lower_file(dentry, inode);
 755         if (rc)
 756                 return rc;
 757         crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
 758         /* Switch on growing or shrinking file */
 759         if (ia->ia_size > i_size) {
 760                 char zero[] = { 0x00 };
 761
 762                 lower_ia->ia_valid &= ~ATTR_SIZE;
 763                 /* Write a single 0 at the last position of the file;
 764                  * this triggers code that will fill in 0's throughout
 765                  * the intermediate portion of the previous end of the
 766                  * file and the new and of the file */
 767                 rc = ecryptfs_write(inode, zero,
 768                                     (ia->ia_size - 1), 1);
 769         } else { /* ia->ia_size < i_size_read(inode) */
 770                 /* We're chopping off all the pages down to the page
 771                  * in which ia->ia_size is located. Fill in the end of
 772                  * that page from (ia->ia_size & ~PAGE_MASK) to
 773                  * PAGE_SIZE with zeros. */
 774                 size_t num_zeros = (PAGE_SIZE
 775                                     - (ia->ia_size & ~PAGE_MASK));
 776
 777                 if (!(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
 778                         truncate_setsize(inode, ia->ia_size);
 779                         lower_ia->ia_size = ia->ia_size;
 780                         lower_ia->ia_valid |= ATTR_SIZE;
 781                         goto out;
 782                 }
 783                 if (num_zeros) {
 784                         char *zeros_virt;
 785
 786                         zeros_virt = kzalloc(num_zeros, GFP_KERNEL);
 787                         if (!zeros_virt) {
 788                                 rc = -ENOMEM;
 789                                 goto out;
 790                         }
 791                         rc = ecryptfs_write(inode, zeros_virt,
 792                                             ia->ia_size, num_zeros);
 793                         kfree(zeros_virt);
 794                         if (rc) {
 795                                 printk(KERN_ERR "Error attempting to zero out "
 796                                        "the remainder of the end page on "
 797                                        "reducing truncate; rc = [%d]\n", rc);
 798                                 goto out;
 799                         }
 800                 }
 801                 truncate_setsize(inode, ia->ia_size);
 802                 rc = ecryptfs_write_inode_size_to_metadata(inode);
 803                 if (rc) {
 804                         printk(KERN_ERR "Problem with "
 805                                "ecryptfs_write_inode_size_to_metadata; "
 806                                "rc = [%d]\n", rc);
 807                         goto out;
 808                 }
 809                 /* We are reducing the size of the ecryptfs file, and need to
 810                  * know if we need to reduce the size of the lower file. */
 811                 lower_size_before_truncate =
 812                     upper_size_to_lower_size(crypt_stat, i_size);
 813                 lower_size_after_truncate =
 814                     upper_size_to_lower_size(crypt_stat, ia->ia_size);
 815                 if (lower_size_after_truncate < lower_size_before_truncate) {
 816                         lower_ia->ia_size = lower_size_after_truncate;
 817                         lower_ia->ia_valid |= ATTR_SIZE;
 818                 } else
 819                         lower_ia->ia_valid &= ~ATTR_SIZE;
 820         }
 821 out:
 822         ecryptfs_put_lower_file(inode);
 823         return rc;
 824 }
 825
 826 static int ecryptfs_inode_newsize_ok(struct inode *inode, loff_t offset)
 827 {
 828         struct ecryptfs_crypt_stat *crypt_stat;
 829         loff_t lower_oldsize, lower_newsize;
 830
 831         crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
 832         lower_oldsize = upper_size_to_lower_size(crypt_stat,
 833                                                  i_size_read(inode));
 834         lower_newsize = upper_size_to_lower_size(crypt_stat, offset);
 835         if (lower_newsize > lower_oldsize) {
 836                 /*
 837                  * The eCryptfs inode and the new *lower* size are mixed here
 838                  * because we may not have the lower i_mutex held and/or it may
 839                  * not be appropriate to call inode_newsize_ok() with inodes
 840                  * from other filesystems.
 841                  */
 842                 return inode_newsize_ok(inode, lower_newsize);
 843         }
 844
 845         return 0;
 846 }
 847
 848 /**
 849  * ecryptfs_truncate
 850  * @dentry: The ecryptfs layer dentry
 851  * @new_length: The length to expand the file to
 852  *
 853  * Simple function that handles the truncation of an eCryptfs inode and
 854  * its corresponding lower inode.
 855  *
 856  * Returns zero on success; non-zero otherwise
 857  */
 858 int ecryptfs_truncate(struct dentry *dentry, loff_t new_length)
 859 {
 860         struct iattr ia = { .ia_valid = ATTR_SIZE, .ia_size = new_length };
 861         struct iattr lower_ia = { .ia_valid = 0 };
 862         int rc;
 863
 864         rc = ecryptfs_inode_newsize_ok(d_inode(dentry), new_length);
 865         if (rc)
 866                 return rc;
 867
 868         rc = truncate_upper(dentry, &ia, &lower_ia);
 869         if (!rc && lower_ia.ia_valid & ATTR_SIZE) {
 870                 struct dentry *lower_dentry = ecryptfs_dentry_to_lower(dentry);
 871
 872                 inode_lock(d_inode(lower_dentry));
 873                 rc = notify_change(&init_user_ns, lower_dentry,
 874                                    &lower_ia, NULL);
 875                 inode_unlock(d_inode(lower_dentry));
 876         }
 877         return rc;
 878 }
 879
 880 static int
 881 ecryptfs_permission(struct user_namespace *mnt_userns, struct inode *inode,
 882                     int mask)
 883 {
 884         return inode_permission(&init_user_ns,
 885                                 ecryptfs_inode_to_lower(inode), mask);
 886 }
 887
 888 /**
 889  * ecryptfs_setattr
 890  * @dentry: dentry handle to the inode to modify
 891  * @ia: Structure with flags of what to change and values
 892  *
 893  * Updates the metadata of an inode. If the update is to the size
 894  * i.e. truncation, then ecryptfs_truncate will handle the size modification
 895  * of both the ecryptfs inode and the lower inode.
 896  *
 897  * All other metadata changes will be passed right to the lower filesystem,
 898  * and we will just update our inode to look like the lower.
 899  */
 900 static int ecryptfs_setattr(struct user_namespace *mnt_userns,
 901                             struct dentry *dentry, struct iattr *ia)
 902 {
 903         int rc = 0;
 904         struct dentry *lower_dentry;
 905         struct iattr lower_ia;
 906         struct inode *inode;
 907         struct inode *lower_inode;
 908         struct ecryptfs_crypt_stat *crypt_stat;
 909
 910         crypt_stat = &ecryptfs_inode_to_private(d_inode(dentry))->crypt_stat;
 911         if (!(crypt_stat->flags & ECRYPTFS_STRUCT_INITIALIZED)) {
 912                 rc = ecryptfs_init_crypt_stat(crypt_stat);
 913                 if (rc)
 914                         return rc;
 915         }
 916         inode = d_inode(dentry);
 917         lower_inode = ecryptfs_inode_to_lower(inode);
 918         lower_dentry = ecryptfs_dentry_to_lower(dentry);
 919         mutex_lock(&crypt_stat->cs_mutex);
 920         if (d_is_dir(dentry))
 921                 crypt_stat->flags &= ~(ECRYPTFS_ENCRYPTED);
 922         else if (d_is_reg(dentry)
 923                  && (!(crypt_stat->flags & ECRYPTFS_POLICY_APPLIED)
 924                      || !(crypt_stat->flags & ECRYPTFS_KEY_VALID))) {
 925                 struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 926
 927                 mount_crypt_stat = &ecryptfs_superblock_to_private(
 928                         dentry->d_sb)->mount_crypt_stat;
 929                 rc = ecryptfs_get_lower_file(dentry, inode);
 930                 if (rc) {
 931                         mutex_unlock(&crypt_stat->cs_mutex);
 932                         goto out;
 933                 }
 934                 rc = ecryptfs_read_metadata(dentry);
 935                 ecryptfs_put_lower_file(inode);
 936                 if (rc) {
 937                         if (!(mount_crypt_stat->flags
 938                               & ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED)) {
 939                                 rc = -EIO;
 940                                 printk(KERN_WARNING "Either the lower file "
 941                                        "is not in a valid eCryptfs format, "
 942                                        "or the key could not be retrieved. "
 943                                        "Plaintext passthrough mode is not "
 944                                        "enabled; returning -EIO\n");
 945                                 mutex_unlock(&crypt_stat->cs_mutex);
 946                                 goto out;
 947                         }
 948                         rc = 0;
 949                         crypt_stat->flags &= ~(ECRYPTFS_I_SIZE_INITIALIZED
 950                                                | ECRYPTFS_ENCRYPTED);
 951                 }
 952         }
 953         mutex_unlock(&crypt_stat->cs_mutex);
 954
 955         rc = setattr_prepare(&init_user_ns, dentry, ia);
 956         if (rc)
 957                 goto out;
 958         if (ia->ia_valid & ATTR_SIZE) {
 959                 rc = ecryptfs_inode_newsize_ok(inode, ia->ia_size);
 960                 if (rc)
 961                         goto out;
 962         }
 963
 964         memcpy(&lower_ia, ia, sizeof(lower_ia));
 965         if (ia->ia_valid & ATTR_FILE)
 966                 lower_ia.ia_file = ecryptfs_file_to_lower(ia->ia_file);
 967         if (ia->ia_valid & ATTR_SIZE) {
 968                 rc = truncate_upper(dentry, ia, &lower_ia);
 969                 if (rc < 0)
 970                         goto out;
 971         }
 972
 973         /*
 974          * mode change is for clearing setuid/setgid bits. Allow lower fs
 975          * to interpret this in its own way.
 976          */
 977         if (lower_ia.ia_valid & (ATTR_KILL_SUID | ATTR_KILL_SGID))
 978                 lower_ia.ia_valid &= ~ATTR_MODE;
 979
 980         inode_lock(d_inode(lower_dentry));
 981         rc = notify_change(&init_user_ns, lower_dentry, &lower_ia, NULL);
 982         inode_unlock(d_inode(lower_dentry));
 983 out:
 984         fsstack_copy_attr_all(inode, lower_inode);
 985         return rc;
 986 }
 987
 988 static int ecryptfs_getattr_link(struct user_namespace *mnt_userns,
 989                                  const struct path *path, struct kstat *stat,
 990                                  u32 request_mask, unsigned int flags)
 991 {
 992         struct dentry *dentry = path->dentry;
 993         struct ecryptfs_mount_crypt_stat *mount_crypt_stat;
 994         int rc = 0;
 995
 996         mount_crypt_stat = &ecryptfs_superblock_to_private(
 997                                                 dentry->d_sb)->mount_crypt_stat;
 998         generic_fillattr(&init_user_ns, d_inode(dentry), stat);
 999         if (mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) {
1000                 char *target;
1001                 size_t targetsiz;
1002
1003                 target = ecryptfs_readlink_lower(dentry, &targetsiz);
1004                 if (!IS_ERR(target)) {
1005                         kfree(target);
1006                         stat->size = targetsiz;
1007                 } else {
1008                         rc = PTR_ERR(target);
1009                 }
1010         }
1011         return rc;
1012 }
1013
1014 static int ecryptfs_getattr(struct user_namespace *mnt_userns,
1015                             const struct path *path, struct kstat *stat,
1016                             u32 request_mask, unsigned int flags)
1017 {
1018         struct dentry *dentry = path->dentry;
1019         struct kstat lower_stat;
1020         int rc;
1021
1022         rc = vfs_getattr(ecryptfs_dentry_to_lower_path(dentry), &lower_stat,
1023                          request_mask, flags);
1024         if (!rc) {
1025                 fsstack_copy_attr_all(d_inode(dentry),
1026                                       ecryptfs_inode_to_lower(d_inode(dentry)));
1027                 generic_fillattr(&init_user_ns, d_inode(dentry), stat);
1028                 stat->blocks = lower_stat.blocks;
1029         }
1030         return rc;
1031 }
1032
1033 int
1034 ecryptfs_setxattr(struct dentry *dentry, struct inode *inode,
1035                   const char *name, const void *value,
1036                   size_t size, int flags)
1037 {
1038         int rc;
1039         struct dentry *lower_dentry;
1040         struct inode *lower_inode;
1041
1042         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1043         lower_inode = d_inode(lower_dentry);
1044         if (!(lower_inode->i_opflags & IOP_XATTR)) {
1045                 rc = -EOPNOTSUPP;
1046                 goto out;
1047         }
1048         inode_lock(lower_inode);
1049         rc = __vfs_setxattr_locked(&init_user_ns, lower_dentry, name, value, size, flags, NULL);
1050         inode_unlock(lower_inode);
1051         if (!rc && inode)
1052                 fsstack_copy_attr_all(inode, lower_inode);
1053 out:
1054         return rc;
1055 }
1056
1057 ssize_t
1058 ecryptfs_getxattr_lower(struct dentry *lower_dentry, struct inode *lower_inode,
1059                         const char *name, void *value, size_t size)
1060 {
1061         int rc;
1062
1063         if (!(lower_inode->i_opflags & IOP_XATTR)) {
1064                 rc = -EOPNOTSUPP;
1065                 goto out;
1066         }
1067         inode_lock(lower_inode);
1068         rc = __vfs_getxattr(lower_dentry, lower_inode, name, value, size);
1069         inode_unlock(lower_inode);
1070 out:
1071         return rc;
1072 }
1073
1074 static ssize_t
1075 ecryptfs_getxattr(struct dentry *dentry, struct inode *inode,
1076                   const char *name, void *value, size_t size)
1077 {
1078         return ecryptfs_getxattr_lower(ecryptfs_dentry_to_lower(dentry),
1079                                        ecryptfs_inode_to_lower(inode),
1080                                        name, value, size);
1081 }
1082
1083 static ssize_t
1084 ecryptfs_listxattr(struct dentry *dentry, char *list, size_t size)
1085 {
1086         int rc = 0;
1087         struct dentry *lower_dentry;
1088
1089         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1090         if (!d_inode(lower_dentry)->i_op->listxattr) {
1091                 rc = -EOPNOTSUPP;
1092                 goto out;
1093         }
1094         inode_lock(d_inode(lower_dentry));
1095         rc = d_inode(lower_dentry)->i_op->listxattr(lower_dentry, list, size);
1096         inode_unlock(d_inode(lower_dentry));
1097 out:
1098         return rc;
1099 }
1100
1101 static int ecryptfs_removexattr(struct dentry *dentry, struct inode *inode,
1102                                 const char *name)
1103 {
1104         int rc;
1105         struct dentry *lower_dentry;
1106         struct inode *lower_inode;
1107
1108         lower_dentry = ecryptfs_dentry_to_lower(dentry);
1109         lower_inode = ecryptfs_inode_to_lower(inode);
1110         if (!(lower_inode->i_opflags & IOP_XATTR)) {
1111                 rc = -EOPNOTSUPP;
1112                 goto out;
1113         }
1114         inode_lock(lower_inode);
1115         rc = __vfs_removexattr(&init_user_ns, lower_dentry, name);
1116         inode_unlock(lower_inode);
1117 out:
1118         return rc;
1119 }
1120
1121 const struct inode_operations ecryptfs_symlink_iops = {
1122         .get_link = ecryptfs_get_link,
1123         .permission = ecryptfs_permission,
1124         .setattr = ecryptfs_setattr,
1125         .getattr = ecryptfs_getattr_link,
1126         .listxattr = ecryptfs_listxattr,
1127 };
1128
1129 const struct inode_operations ecryptfs_dir_iops = {
1130         .create = ecryptfs_create,
1131         .lookup = ecryptfs_lookup,
1132         .link = ecryptfs_link,
1133         .unlink = ecryptfs_unlink,
1134         .symlink = ecryptfs_symlink,
1135         .mkdir = ecryptfs_mkdir,
1136         .rmdir = ecryptfs_rmdir,
1137         .mknod = ecryptfs_mknod,
1138         .rename = ecryptfs_rename,
1139         .permission = ecryptfs_permission,
1140         .setattr = ecryptfs_setattr,
1141         .listxattr = ecryptfs_listxattr,
1142 };
1143
1144 const struct inode_operations ecryptfs_main_iops = {
1145         .permission = ecryptfs_permission,
1146         .setattr = ecryptfs_setattr,
1147         .getattr = ecryptfs_getattr,
1148         .listxattr = ecryptfs_listxattr,
1149 };
1150
1151 static int ecryptfs_xattr_get(const struct xattr_handler *handler,
1152                               struct dentry *dentry, struct inode *inode,
1153                               const char *name, void *buffer, size_t size)
1154 {
1155         return ecryptfs_getxattr(dentry, inode, name, buffer, size);
1156 }
1157
1158 static int ecryptfs_xattr_set(const struct xattr_handler *handler,
1159                               struct user_namespace *mnt_userns,
1160                               struct dentry *dentry, struct inode *inode,
1161                               const char *name, const void *value, size_t size,
1162                               int flags)
1163 {
1164         if (value)
1165                 return ecryptfs_setxattr(dentry, inode, name, value, size, flags);
1166         else {
1167                 BUG_ON(flags != XATTR_REPLACE);
1168                 return ecryptfs_removexattr(dentry, inode, name);
1169         }
1170 }
1171
1172 static const struct xattr_handler ecryptfs_xattr_handler = {
1173         .prefix = "",  /* match anything */
1174         .get = ecryptfs_xattr_get,
1175         .set = ecryptfs_xattr_set,
1176 };
1177
1178 const struct xattr_handler *ecryptfs_xattr_handlers[] = {
1179         &ecryptfs_xattr_handler,
1180         NULL
1181 };