Commit | Line | Data |
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1e51764a AB |
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 | ||
073aaa1b | 58 | #include "ubifs.h" |
7dcda1c9 | 59 | #include <linux/fs.h> |
5a0e3ad6 | 60 | #include <linux/slab.h> |
1e51764a | 61 | #include <linux/xattr.h> |
1e51764a AB |
62 | |
63 | /* | |
64 | * Limit the number of extended attributes per inode so that the total size | |
c78c7e35 | 65 | * (@xattr_size) is guaranteeded to fit in an 'unsigned int'. |
1e51764a AB |
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 | ||
14ffd5d0 SD |
82 | static const struct inode_operations empty_iops; |
83 | static const struct file_operations empty_fops; | |
1e51764a AB |
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 qstr *nm, const void *value, int size) | |
101 | { | |
fee1756d | 102 | int err, names_len; |
1e51764a AB |
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, | |
5acd6ff8 ZS |
106 | .new_ino_d = ALIGN(size, 8), .dirtied_ino = 1, |
107 | .dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; | |
1e51764a | 108 | |
fee1756d | 109 | if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE) { |
235c362b | 110 | ubifs_err(c, "inode %lu already has too many xattrs (%d), cannot create more", |
fee1756d | 111 | host->i_ino, host_ui->xattr_cnt); |
1e51764a | 112 | return -ENOSPC; |
fee1756d | 113 | } |
1e51764a AB |
114 | /* |
115 | * Linux limits the maximum size of the extended attribute names list | |
c78c7e35 | 116 | * to %XATTR_LIST_MAX. This means we should not allow creating more |
1e51764a AB |
117 | * extended attributes if the name list becomes larger. This limitation |
118 | * is artificial for UBIFS, though. | |
119 | */ | |
fee1756d SN |
120 | names_len = host_ui->xattr_names + host_ui->xattr_cnt + nm->len + 1; |
121 | if (names_len > XATTR_LIST_MAX) { | |
235c362b | 122 | ubifs_err(c, "cannot add one more xattr name to inode %lu, total names length would become %d, max. is %d", |
fee1756d | 123 | host->i_ino, names_len, XATTR_LIST_MAX); |
1e51764a | 124 | return -ENOSPC; |
fee1756d | 125 | } |
1e51764a AB |
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 | ||
1e51764a | 137 | /* Re-define all operations to be "nothing" */ |
7dcda1c9 | 138 | inode->i_mapping->a_ops = &empty_aops; |
14ffd5d0 SD |
139 | inode->i_op = &empty_iops; |
140 | inode->i_fop = &empty_fops; | |
1e51764a AB |
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; | |
eaecf43a | 146 | ui->data = kmemdup(value, size, GFP_NOFS); |
1e51764a AB |
147 | if (!ui->data) { |
148 | err = -ENOMEM; | |
c78c7e35 | 149 | goto out_free; |
1e51764a | 150 | } |
c78c7e35 AB |
151 | inode->i_size = ui->ui_size = size; |
152 | ui->data_len = size; | |
153 | ||
154 | mutex_lock(&host_ui->ui_mutex); | |
1e51764a AB |
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 | ||
1e51764a AB |
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); | |
1e51764a | 175 | mutex_unlock(&host_ui->ui_mutex); |
c78c7e35 | 176 | out_free: |
1e51764a AB |
177 | make_bad_inode(inode); |
178 | iput(inode); | |
179 | out_budg: | |
180 | ubifs_release_budget(c, &req); | |
181 | return err; | |
182 | } | |
183 | ||
184 | /** | |
185 | * change_xattr - change an extended attribute. | |
186 | * @c: UBIFS file-system description object | |
187 | * @host: host inode | |
188 | * @inode: extended attribute inode | |
189 | * @value: extended attribute value | |
190 | * @size: size of extended attribute value | |
191 | * | |
192 | * This helper function changes the value of extended attribute @inode with new | |
193 | * data from @value. Returns zero in case of success and a negative error code | |
194 | * in case of failure. | |
195 | */ | |
196 | static int change_xattr(struct ubifs_info *c, struct inode *host, | |
197 | struct inode *inode, const void *value, int size) | |
198 | { | |
199 | int err; | |
200 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
201 | struct ubifs_inode *ui = ubifs_inode(inode); | |
ab92a20b | 202 | void *buf = NULL; |
1e51764a | 203 | struct ubifs_budget_req req = { .dirtied_ino = 2, |
5acd6ff8 | 204 | .dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) }; |
1e51764a AB |
205 | |
206 | ubifs_assert(ui->data_len == inode->i_size); | |
207 | err = ubifs_budget_space(c, &req); | |
208 | if (err) | |
209 | return err; | |
210 | ||
ab92a20b DY |
211 | buf = kmemdup(value, size, GFP_NOFS); |
212 | if (!buf) { | |
1e51764a | 213 | err = -ENOMEM; |
c78c7e35 | 214 | goto out_free; |
1e51764a | 215 | } |
ab92a20b DY |
216 | mutex_lock(&ui->ui_mutex); |
217 | kfree(ui->data); | |
218 | ui->data = buf; | |
1e51764a AB |
219 | inode->i_size = ui->ui_size = size; |
220 | ui->data_len = size; | |
ab92a20b | 221 | mutex_unlock(&ui->ui_mutex); |
1e51764a | 222 | |
c78c7e35 AB |
223 | mutex_lock(&host_ui->ui_mutex); |
224 | host->i_ctime = ubifs_current_time(host); | |
225 | host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len); | |
226 | host_ui->xattr_size += CALC_XATTR_BYTES(size); | |
227 | ||
1e51764a AB |
228 | /* |
229 | * It is important to write the host inode after the xattr inode | |
230 | * because if the host inode gets synchronized (via 'fsync()'), then | |
231 | * the extended attribute inode gets synchronized, because it goes | |
232 | * before the host inode in the write-buffer. | |
233 | */ | |
234 | err = ubifs_jnl_change_xattr(c, inode, host); | |
235 | if (err) | |
236 | goto out_cancel; | |
237 | mutex_unlock(&host_ui->ui_mutex); | |
238 | ||
239 | ubifs_release_budget(c, &req); | |
240 | return 0; | |
241 | ||
242 | out_cancel: | |
243 | host_ui->xattr_size -= CALC_XATTR_BYTES(size); | |
244 | host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); | |
1e51764a | 245 | mutex_unlock(&host_ui->ui_mutex); |
c78c7e35 AB |
246 | make_bad_inode(inode); |
247 | out_free: | |
1e51764a AB |
248 | ubifs_release_budget(c, &req); |
249 | return err; | |
250 | } | |
251 | ||
252 | /** | |
253 | * check_namespace - check extended attribute name-space. | |
254 | * @nm: extended attribute name | |
255 | * | |
256 | * This function makes sure the extended attribute name belongs to one of the | |
257 | * supported extended attribute name-spaces. Returns name-space index in case | |
258 | * of success and a negative error code in case of failure. | |
259 | */ | |
260 | static int check_namespace(const struct qstr *nm) | |
261 | { | |
262 | int type; | |
263 | ||
264 | if (nm->len > UBIFS_MAX_NLEN) | |
265 | return -ENAMETOOLONG; | |
266 | ||
267 | if (!strncmp(nm->name, XATTR_TRUSTED_PREFIX, | |
268 | XATTR_TRUSTED_PREFIX_LEN)) { | |
4fdd1d51 | 269 | if (nm->name[XATTR_TRUSTED_PREFIX_LEN] == '\0') |
1e51764a AB |
270 | return -EINVAL; |
271 | type = TRUSTED_XATTR; | |
272 | } else if (!strncmp(nm->name, XATTR_USER_PREFIX, | |
273 | XATTR_USER_PREFIX_LEN)) { | |
274 | if (nm->name[XATTR_USER_PREFIX_LEN] == '\0') | |
275 | return -EINVAL; | |
276 | type = USER_XATTR; | |
277 | } else if (!strncmp(nm->name, XATTR_SECURITY_PREFIX, | |
278 | XATTR_SECURITY_PREFIX_LEN)) { | |
4fdd1d51 | 279 | if (nm->name[XATTR_SECURITY_PREFIX_LEN] == '\0') |
1e51764a AB |
280 | return -EINVAL; |
281 | type = SECURITY_XATTR; | |
282 | } else | |
283 | return -EOPNOTSUPP; | |
284 | ||
285 | return type; | |
286 | } | |
287 | ||
288 | static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum) | |
289 | { | |
290 | struct inode *inode; | |
291 | ||
292 | inode = ubifs_iget(c->vfs_sb, inum); | |
293 | if (IS_ERR(inode)) { | |
235c362b | 294 | ubifs_err(c, "dead extended attribute entry, error %d", |
1e51764a AB |
295 | (int)PTR_ERR(inode)); |
296 | return inode; | |
297 | } | |
298 | if (ubifs_inode(inode)->xattr) | |
299 | return inode; | |
235c362b | 300 | ubifs_err(c, "corrupt extended attribute entry"); |
1e51764a AB |
301 | iput(inode); |
302 | return ERR_PTR(-EINVAL); | |
303 | } | |
304 | ||
895d9db2 SN |
305 | static int setxattr(struct inode *host, const char *name, const void *value, |
306 | size_t size, int flags) | |
1e51764a | 307 | { |
895d9db2 | 308 | struct inode *inode; |
1e51764a | 309 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 310 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
311 | struct ubifs_dent_node *xent; |
312 | union ubifs_key key; | |
313 | int err, type; | |
314 | ||
5955102c | 315 | ubifs_assert(inode_is_locked(host)); |
1e51764a AB |
316 | |
317 | if (size > UBIFS_MAX_INO_DATA) | |
318 | return -ERANGE; | |
319 | ||
320 | type = check_namespace(&nm); | |
321 | if (type < 0) | |
322 | return type; | |
323 | ||
324 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
325 | if (!xent) | |
326 | return -ENOMEM; | |
327 | ||
328 | /* | |
329 | * The extended attribute entries are stored in LNC, so multiple | |
330 | * look-ups do not involve reading the flash. | |
331 | */ | |
332 | xent_key_init(c, &key, host->i_ino, &nm); | |
333 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
334 | if (err) { | |
335 | if (err != -ENOENT) | |
336 | goto out_free; | |
337 | ||
338 | if (flags & XATTR_REPLACE) | |
339 | /* We are asked not to create the xattr */ | |
340 | err = -ENODATA; | |
341 | else | |
342 | err = create_xattr(c, host, &nm, value, size); | |
343 | goto out_free; | |
344 | } | |
345 | ||
346 | if (flags & XATTR_CREATE) { | |
347 | /* We are asked not to replace the xattr */ | |
348 | err = -EEXIST; | |
349 | goto out_free; | |
350 | } | |
351 | ||
352 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
353 | if (IS_ERR(inode)) { | |
354 | err = PTR_ERR(inode); | |
355 | goto out_free; | |
356 | } | |
357 | ||
358 | err = change_xattr(c, host, inode, value, size); | |
359 | iput(inode); | |
360 | ||
361 | out_free: | |
362 | kfree(xent); | |
363 | return err; | |
364 | } | |
365 | ||
895d9db2 SN |
366 | int ubifs_setxattr(struct dentry *dentry, const char *name, |
367 | const void *value, size_t size, int flags) | |
368 | { | |
369 | dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd", | |
2b0143b5 | 370 | name, d_inode(dentry)->i_ino, dentry, size); |
895d9db2 | 371 | |
2b0143b5 | 372 | return setxattr(d_inode(dentry), name, value, size, flags); |
895d9db2 SN |
373 | } |
374 | ||
1e51764a AB |
375 | ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf, |
376 | size_t size) | |
377 | { | |
2b0143b5 | 378 | struct inode *inode, *host = d_inode(dentry); |
1e51764a | 379 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 380 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
381 | struct ubifs_inode *ui; |
382 | struct ubifs_dent_node *xent; | |
383 | union ubifs_key key; | |
384 | int err; | |
385 | ||
4cb2a01d AV |
386 | dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name, |
387 | host->i_ino, dentry, size); | |
1e51764a AB |
388 | |
389 | err = check_namespace(&nm); | |
390 | if (err < 0) | |
391 | return err; | |
392 | ||
393 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
394 | if (!xent) | |
395 | return -ENOMEM; | |
396 | ||
1e51764a AB |
397 | xent_key_init(c, &key, host->i_ino, &nm); |
398 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
399 | if (err) { | |
400 | if (err == -ENOENT) | |
401 | err = -ENODATA; | |
402 | goto out_unlock; | |
403 | } | |
404 | ||
405 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
406 | if (IS_ERR(inode)) { | |
407 | err = PTR_ERR(inode); | |
408 | goto out_unlock; | |
409 | } | |
410 | ||
411 | ui = ubifs_inode(inode); | |
412 | ubifs_assert(inode->i_size == ui->data_len); | |
413 | ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len); | |
414 | ||
ab92a20b | 415 | mutex_lock(&ui->ui_mutex); |
1e51764a AB |
416 | if (buf) { |
417 | /* If @buf is %NULL we are supposed to return the length */ | |
418 | if (ui->data_len > size) { | |
235c362b | 419 | ubifs_err(c, "buffer size %zd, xattr len %d", |
a6aae4dd | 420 | size, ui->data_len); |
1e51764a AB |
421 | err = -ERANGE; |
422 | goto out_iput; | |
423 | } | |
424 | ||
425 | memcpy(buf, ui->data, ui->data_len); | |
426 | } | |
427 | err = ui->data_len; | |
428 | ||
429 | out_iput: | |
ab92a20b | 430 | mutex_unlock(&ui->ui_mutex); |
1e51764a AB |
431 | iput(inode); |
432 | out_unlock: | |
1e51764a AB |
433 | kfree(xent); |
434 | return err; | |
435 | } | |
436 | ||
437 | ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size) | |
438 | { | |
439 | union ubifs_key key; | |
2b0143b5 | 440 | struct inode *host = d_inode(dentry); |
1e51764a AB |
441 | struct ubifs_info *c = host->i_sb->s_fs_info; |
442 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
443 | struct ubifs_dent_node *xent, *pxent = NULL; | |
444 | int err, len, written = 0; | |
445 | struct qstr nm = { .name = NULL }; | |
446 | ||
4cb2a01d AV |
447 | dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino, |
448 | dentry, size); | |
1e51764a AB |
449 | |
450 | len = host_ui->xattr_names + host_ui->xattr_cnt; | |
451 | if (!buffer) | |
452 | /* | |
453 | * We should return the minimum buffer size which will fit a | |
454 | * null-terminated list of all the extended attribute names. | |
455 | */ | |
456 | return len; | |
457 | ||
458 | if (len > size) | |
459 | return -ERANGE; | |
460 | ||
461 | lowest_xent_key(c, &key, host->i_ino); | |
1e51764a AB |
462 | while (1) { |
463 | int type; | |
464 | ||
465 | xent = ubifs_tnc_next_ent(c, &key, &nm); | |
8d47aef4 | 466 | if (IS_ERR(xent)) { |
1e51764a AB |
467 | err = PTR_ERR(xent); |
468 | break; | |
469 | } | |
470 | ||
471 | nm.name = xent->name; | |
472 | nm.len = le16_to_cpu(xent->nlen); | |
473 | ||
474 | type = check_namespace(&nm); | |
475 | if (unlikely(type < 0)) { | |
476 | err = type; | |
477 | break; | |
478 | } | |
479 | ||
480 | /* Show trusted namespace only for "power" users */ | |
481 | if (type != TRUSTED_XATTR || capable(CAP_SYS_ADMIN)) { | |
482 | memcpy(buffer + written, nm.name, nm.len + 1); | |
483 | written += nm.len + 1; | |
484 | } | |
485 | ||
486 | kfree(pxent); | |
487 | pxent = xent; | |
488 | key_read(c, &xent->key, &key); | |
489 | } | |
1e51764a AB |
490 | |
491 | kfree(pxent); | |
492 | if (err != -ENOENT) { | |
235c362b | 493 | ubifs_err(c, "cannot find next direntry, error %d", err); |
1e51764a AB |
494 | return err; |
495 | } | |
496 | ||
497 | ubifs_assert(written <= size); | |
498 | return written; | |
499 | } | |
500 | ||
501 | static int remove_xattr(struct ubifs_info *c, struct inode *host, | |
502 | struct inode *inode, const struct qstr *nm) | |
503 | { | |
504 | int err; | |
505 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
506 | struct ubifs_inode *ui = ubifs_inode(inode); | |
5acd6ff8 ZS |
507 | struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1, |
508 | .dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; | |
1e51764a AB |
509 | |
510 | ubifs_assert(ui->data_len == inode->i_size); | |
511 | ||
512 | err = ubifs_budget_space(c, &req); | |
513 | if (err) | |
514 | return err; | |
515 | ||
516 | mutex_lock(&host_ui->ui_mutex); | |
517 | host->i_ctime = ubifs_current_time(host); | |
518 | host_ui->xattr_cnt -= 1; | |
519 | host_ui->xattr_size -= CALC_DENT_SIZE(nm->len); | |
520 | host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len); | |
521 | host_ui->xattr_names -= nm->len; | |
522 | ||
523 | err = ubifs_jnl_delete_xattr(c, host, inode, nm); | |
524 | if (err) | |
525 | goto out_cancel; | |
526 | mutex_unlock(&host_ui->ui_mutex); | |
527 | ||
528 | ubifs_release_budget(c, &req); | |
529 | return 0; | |
530 | ||
531 | out_cancel: | |
532 | host_ui->xattr_cnt += 1; | |
533 | host_ui->xattr_size += CALC_DENT_SIZE(nm->len); | |
534 | host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); | |
535 | mutex_unlock(&host_ui->ui_mutex); | |
536 | ubifs_release_budget(c, &req); | |
537 | make_bad_inode(inode); | |
538 | return err; | |
539 | } | |
540 | ||
541 | int ubifs_removexattr(struct dentry *dentry, const char *name) | |
542 | { | |
2b0143b5 | 543 | struct inode *inode, *host = d_inode(dentry); |
1e51764a | 544 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 545 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
546 | struct ubifs_dent_node *xent; |
547 | union ubifs_key key; | |
548 | int err; | |
549 | ||
4cb2a01d AV |
550 | dbg_gen("xattr '%s', ino %lu ('%pd')", name, |
551 | host->i_ino, dentry); | |
5955102c | 552 | ubifs_assert(inode_is_locked(host)); |
1e51764a AB |
553 | |
554 | err = check_namespace(&nm); | |
555 | if (err < 0) | |
556 | return err; | |
557 | ||
558 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
559 | if (!xent) | |
560 | return -ENOMEM; | |
561 | ||
562 | xent_key_init(c, &key, host->i_ino, &nm); | |
563 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
564 | if (err) { | |
565 | if (err == -ENOENT) | |
566 | err = -ENODATA; | |
567 | goto out_free; | |
568 | } | |
569 | ||
570 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
571 | if (IS_ERR(inode)) { | |
572 | err = PTR_ERR(inode); | |
573 | goto out_free; | |
574 | } | |
575 | ||
576 | ubifs_assert(inode->i_nlink == 1); | |
6d6b77f1 | 577 | clear_nlink(inode); |
1e51764a AB |
578 | err = remove_xattr(c, host, inode, &nm); |
579 | if (err) | |
bfe86848 | 580 | set_nlink(inode, 1); |
1e51764a AB |
581 | |
582 | /* If @i_nlink is 0, 'iput()' will delete the inode */ | |
583 | iput(inode); | |
584 | ||
585 | out_free: | |
586 | kfree(xent); | |
587 | return err; | |
588 | } | |
d7f0b70d | 589 | |
d7f0b70d SN |
590 | static int init_xattrs(struct inode *inode, const struct xattr *xattr_array, |
591 | void *fs_info) | |
592 | { | |
593 | const struct xattr *xattr; | |
594 | char *name; | |
595 | int err = 0; | |
596 | ||
597 | for (xattr = xattr_array; xattr->name != NULL; xattr++) { | |
598 | name = kmalloc(XATTR_SECURITY_PREFIX_LEN + | |
599 | strlen(xattr->name) + 1, GFP_NOFS); | |
600 | if (!name) { | |
601 | err = -ENOMEM; | |
602 | break; | |
603 | } | |
604 | strcpy(name, XATTR_SECURITY_PREFIX); | |
605 | strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); | |
606 | err = setxattr(inode, name, xattr->value, xattr->value_len, 0); | |
607 | kfree(name); | |
608 | if (err < 0) | |
609 | break; | |
610 | } | |
611 | ||
612 | return err; | |
613 | } | |
614 | ||
615 | int ubifs_init_security(struct inode *dentry, struct inode *inode, | |
616 | const struct qstr *qstr) | |
617 | { | |
618 | int err; | |
619 | ||
d7f0b70d SN |
620 | err = security_inode_init_security(inode, dentry, qstr, |
621 | &init_xattrs, 0); | |
235c362b SY |
622 | if (err) { |
623 | struct ubifs_info *c = dentry->i_sb->s_fs_info; | |
624 | ubifs_err(c, "cannot initialize security for inode %lu, error %d", | |
fee1756d | 625 | inode->i_ino, err); |
235c362b | 626 | } |
d7f0b70d SN |
627 | return err; |
628 | } |