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 AB |
61 | #include <linux/xattr.h> |
62 | #include <linux/posix_acl_xattr.h> | |
1e51764a AB |
63 | |
64 | /* | |
65 | * Limit the number of extended attributes per inode so that the total size | |
c78c7e35 | 66 | * (@xattr_size) is guaranteeded to fit in an 'unsigned int'. |
1e51764a AB |
67 | */ |
68 | #define MAX_XATTRS_PER_INODE 65535 | |
69 | ||
70 | /* | |
71 | * Extended attribute type constants. | |
72 | * | |
73 | * USER_XATTR: user extended attribute ("user.*") | |
74 | * TRUSTED_XATTR: trusted extended attribute ("trusted.*) | |
75 | * SECURITY_XATTR: security extended attribute ("security.*") | |
76 | */ | |
77 | enum { | |
78 | USER_XATTR, | |
79 | TRUSTED_XATTR, | |
80 | SECURITY_XATTR, | |
81 | }; | |
82 | ||
14ffd5d0 SD |
83 | static const struct inode_operations empty_iops; |
84 | static const struct file_operations empty_fops; | |
1e51764a AB |
85 | |
86 | /** | |
87 | * create_xattr - create an extended attribute. | |
88 | * @c: UBIFS file-system description object | |
89 | * @host: host inode | |
90 | * @nm: extended attribute name | |
91 | * @value: extended attribute value | |
92 | * @size: size of extended attribute value | |
93 | * | |
94 | * This is a helper function which creates an extended attribute of name @nm | |
95 | * and value @value for inode @host. The host inode is also updated on flash | |
96 | * because the ctime and extended attribute accounting data changes. This | |
97 | * function returns zero in case of success and a negative error code in case | |
98 | * of failure. | |
99 | */ | |
100 | static int create_xattr(struct ubifs_info *c, struct inode *host, | |
101 | const struct qstr *nm, const void *value, int size) | |
102 | { | |
fee1756d | 103 | int err, names_len; |
1e51764a AB |
104 | struct inode *inode; |
105 | struct ubifs_inode *ui, *host_ui = ubifs_inode(host); | |
106 | struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1, | |
5acd6ff8 ZS |
107 | .new_ino_d = ALIGN(size, 8), .dirtied_ino = 1, |
108 | .dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; | |
1e51764a | 109 | |
fee1756d | 110 | if (host_ui->xattr_cnt >= MAX_XATTRS_PER_INODE) { |
235c362b | 111 | ubifs_err(c, "inode %lu already has too many xattrs (%d), cannot create more", |
fee1756d | 112 | host->i_ino, host_ui->xattr_cnt); |
1e51764a | 113 | return -ENOSPC; |
fee1756d | 114 | } |
1e51764a AB |
115 | /* |
116 | * Linux limits the maximum size of the extended attribute names list | |
c78c7e35 | 117 | * to %XATTR_LIST_MAX. This means we should not allow creating more |
1e51764a AB |
118 | * extended attributes if the name list becomes larger. This limitation |
119 | * is artificial for UBIFS, though. | |
120 | */ | |
fee1756d SN |
121 | names_len = host_ui->xattr_names + host_ui->xattr_cnt + nm->len + 1; |
122 | if (names_len > XATTR_LIST_MAX) { | |
235c362b | 123 | ubifs_err(c, "cannot add one more xattr name to inode %lu, total names length would become %d, max. is %d", |
fee1756d | 124 | host->i_ino, names_len, XATTR_LIST_MAX); |
1e51764a | 125 | return -ENOSPC; |
fee1756d | 126 | } |
1e51764a AB |
127 | |
128 | err = ubifs_budget_space(c, &req); | |
129 | if (err) | |
130 | return err; | |
131 | ||
132 | inode = ubifs_new_inode(c, host, S_IFREG | S_IRWXUGO); | |
133 | if (IS_ERR(inode)) { | |
134 | err = PTR_ERR(inode); | |
135 | goto out_budg; | |
136 | } | |
137 | ||
1e51764a | 138 | /* Re-define all operations to be "nothing" */ |
7dcda1c9 | 139 | inode->i_mapping->a_ops = &empty_aops; |
14ffd5d0 SD |
140 | inode->i_op = &empty_iops; |
141 | inode->i_fop = &empty_fops; | |
1e51764a AB |
142 | |
143 | inode->i_flags |= S_SYNC | S_NOATIME | S_NOCMTIME | S_NOQUOTA; | |
144 | ui = ubifs_inode(inode); | |
145 | ui->xattr = 1; | |
146 | ui->flags |= UBIFS_XATTR_FL; | |
eaecf43a | 147 | ui->data = kmemdup(value, size, GFP_NOFS); |
1e51764a AB |
148 | if (!ui->data) { |
149 | err = -ENOMEM; | |
c78c7e35 | 150 | goto out_free; |
1e51764a | 151 | } |
c78c7e35 AB |
152 | inode->i_size = ui->ui_size = size; |
153 | ui->data_len = size; | |
154 | ||
155 | mutex_lock(&host_ui->ui_mutex); | |
1e51764a AB |
156 | host->i_ctime = ubifs_current_time(host); |
157 | host_ui->xattr_cnt += 1; | |
158 | host_ui->xattr_size += CALC_DENT_SIZE(nm->len); | |
159 | host_ui->xattr_size += CALC_XATTR_BYTES(size); | |
160 | host_ui->xattr_names += nm->len; | |
161 | ||
1e51764a AB |
162 | err = ubifs_jnl_update(c, host, nm, inode, 0, 1); |
163 | if (err) | |
164 | goto out_cancel; | |
165 | mutex_unlock(&host_ui->ui_mutex); | |
166 | ||
167 | ubifs_release_budget(c, &req); | |
168 | insert_inode_hash(inode); | |
169 | iput(inode); | |
170 | return 0; | |
171 | ||
172 | out_cancel: | |
173 | host_ui->xattr_cnt -= 1; | |
174 | host_ui->xattr_size -= CALC_DENT_SIZE(nm->len); | |
175 | host_ui->xattr_size -= CALC_XATTR_BYTES(size); | |
1e51764a | 176 | mutex_unlock(&host_ui->ui_mutex); |
c78c7e35 | 177 | out_free: |
1e51764a AB |
178 | make_bad_inode(inode); |
179 | iput(inode); | |
180 | out_budg: | |
181 | ubifs_release_budget(c, &req); | |
182 | return err; | |
183 | } | |
184 | ||
185 | /** | |
186 | * change_xattr - change an extended attribute. | |
187 | * @c: UBIFS file-system description object | |
188 | * @host: host inode | |
189 | * @inode: extended attribute inode | |
190 | * @value: extended attribute value | |
191 | * @size: size of extended attribute value | |
192 | * | |
193 | * This helper function changes the value of extended attribute @inode with new | |
194 | * data from @value. Returns zero in case of success and a negative error code | |
195 | * in case of failure. | |
196 | */ | |
197 | static int change_xattr(struct ubifs_info *c, struct inode *host, | |
198 | struct inode *inode, const void *value, int size) | |
199 | { | |
200 | int err; | |
201 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
202 | struct ubifs_inode *ui = ubifs_inode(inode); | |
ab92a20b | 203 | void *buf = NULL; |
1e51764a | 204 | struct ubifs_budget_req req = { .dirtied_ino = 2, |
5acd6ff8 | 205 | .dirtied_ino_d = ALIGN(size, 8) + ALIGN(host_ui->data_len, 8) }; |
1e51764a AB |
206 | |
207 | ubifs_assert(ui->data_len == inode->i_size); | |
208 | err = ubifs_budget_space(c, &req); | |
209 | if (err) | |
210 | return err; | |
211 | ||
ab92a20b DY |
212 | buf = kmemdup(value, size, GFP_NOFS); |
213 | if (!buf) { | |
1e51764a | 214 | err = -ENOMEM; |
c78c7e35 | 215 | goto out_free; |
1e51764a | 216 | } |
ab92a20b DY |
217 | mutex_lock(&ui->ui_mutex); |
218 | kfree(ui->data); | |
219 | ui->data = buf; | |
1e51764a AB |
220 | inode->i_size = ui->ui_size = size; |
221 | ui->data_len = size; | |
ab92a20b | 222 | mutex_unlock(&ui->ui_mutex); |
1e51764a | 223 | |
c78c7e35 AB |
224 | mutex_lock(&host_ui->ui_mutex); |
225 | host->i_ctime = ubifs_current_time(host); | |
226 | host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len); | |
227 | host_ui->xattr_size += CALC_XATTR_BYTES(size); | |
228 | ||
1e51764a AB |
229 | /* |
230 | * It is important to write the host inode after the xattr inode | |
231 | * because if the host inode gets synchronized (via 'fsync()'), then | |
232 | * the extended attribute inode gets synchronized, because it goes | |
233 | * before the host inode in the write-buffer. | |
234 | */ | |
235 | err = ubifs_jnl_change_xattr(c, inode, host); | |
236 | if (err) | |
237 | goto out_cancel; | |
238 | mutex_unlock(&host_ui->ui_mutex); | |
239 | ||
240 | ubifs_release_budget(c, &req); | |
241 | return 0; | |
242 | ||
243 | out_cancel: | |
244 | host_ui->xattr_size -= CALC_XATTR_BYTES(size); | |
245 | host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); | |
1e51764a | 246 | mutex_unlock(&host_ui->ui_mutex); |
c78c7e35 AB |
247 | make_bad_inode(inode); |
248 | out_free: | |
1e51764a AB |
249 | ubifs_release_budget(c, &req); |
250 | return err; | |
251 | } | |
252 | ||
253 | /** | |
254 | * check_namespace - check extended attribute name-space. | |
255 | * @nm: extended attribute name | |
256 | * | |
257 | * This function makes sure the extended attribute name belongs to one of the | |
258 | * supported extended attribute name-spaces. Returns name-space index in case | |
259 | * of success and a negative error code in case of failure. | |
260 | */ | |
261 | static int check_namespace(const struct qstr *nm) | |
262 | { | |
263 | int type; | |
264 | ||
265 | if (nm->len > UBIFS_MAX_NLEN) | |
266 | return -ENAMETOOLONG; | |
267 | ||
268 | if (!strncmp(nm->name, XATTR_TRUSTED_PREFIX, | |
269 | XATTR_TRUSTED_PREFIX_LEN)) { | |
4fdd1d51 | 270 | if (nm->name[XATTR_TRUSTED_PREFIX_LEN] == '\0') |
1e51764a AB |
271 | return -EINVAL; |
272 | type = TRUSTED_XATTR; | |
273 | } else if (!strncmp(nm->name, XATTR_USER_PREFIX, | |
274 | XATTR_USER_PREFIX_LEN)) { | |
275 | if (nm->name[XATTR_USER_PREFIX_LEN] == '\0') | |
276 | return -EINVAL; | |
277 | type = USER_XATTR; | |
278 | } else if (!strncmp(nm->name, XATTR_SECURITY_PREFIX, | |
279 | XATTR_SECURITY_PREFIX_LEN)) { | |
4fdd1d51 | 280 | if (nm->name[XATTR_SECURITY_PREFIX_LEN] == '\0') |
1e51764a AB |
281 | return -EINVAL; |
282 | type = SECURITY_XATTR; | |
283 | } else | |
284 | return -EOPNOTSUPP; | |
285 | ||
286 | return type; | |
287 | } | |
288 | ||
289 | static struct inode *iget_xattr(struct ubifs_info *c, ino_t inum) | |
290 | { | |
291 | struct inode *inode; | |
292 | ||
293 | inode = ubifs_iget(c->vfs_sb, inum); | |
294 | if (IS_ERR(inode)) { | |
235c362b | 295 | ubifs_err(c, "dead extended attribute entry, error %d", |
1e51764a AB |
296 | (int)PTR_ERR(inode)); |
297 | return inode; | |
298 | } | |
299 | if (ubifs_inode(inode)->xattr) | |
300 | return inode; | |
235c362b | 301 | ubifs_err(c, "corrupt extended attribute entry"); |
1e51764a AB |
302 | iput(inode); |
303 | return ERR_PTR(-EINVAL); | |
304 | } | |
305 | ||
895d9db2 SN |
306 | static int setxattr(struct inode *host, const char *name, const void *value, |
307 | size_t size, int flags) | |
1e51764a | 308 | { |
895d9db2 | 309 | struct inode *inode; |
1e51764a | 310 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 311 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
312 | struct ubifs_dent_node *xent; |
313 | union ubifs_key key; | |
314 | int err, type; | |
315 | ||
5955102c | 316 | ubifs_assert(inode_is_locked(host)); |
1e51764a AB |
317 | |
318 | if (size > UBIFS_MAX_INO_DATA) | |
319 | return -ERANGE; | |
320 | ||
321 | type = check_namespace(&nm); | |
322 | if (type < 0) | |
323 | return type; | |
324 | ||
325 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
326 | if (!xent) | |
327 | return -ENOMEM; | |
328 | ||
329 | /* | |
330 | * The extended attribute entries are stored in LNC, so multiple | |
331 | * look-ups do not involve reading the flash. | |
332 | */ | |
333 | xent_key_init(c, &key, host->i_ino, &nm); | |
334 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
335 | if (err) { | |
336 | if (err != -ENOENT) | |
337 | goto out_free; | |
338 | ||
339 | if (flags & XATTR_REPLACE) | |
340 | /* We are asked not to create the xattr */ | |
341 | err = -ENODATA; | |
342 | else | |
343 | err = create_xattr(c, host, &nm, value, size); | |
344 | goto out_free; | |
345 | } | |
346 | ||
347 | if (flags & XATTR_CREATE) { | |
348 | /* We are asked not to replace the xattr */ | |
349 | err = -EEXIST; | |
350 | goto out_free; | |
351 | } | |
352 | ||
353 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
354 | if (IS_ERR(inode)) { | |
355 | err = PTR_ERR(inode); | |
356 | goto out_free; | |
357 | } | |
358 | ||
359 | err = change_xattr(c, host, inode, value, size); | |
360 | iput(inode); | |
361 | ||
362 | out_free: | |
363 | kfree(xent); | |
364 | return err; | |
365 | } | |
366 | ||
895d9db2 SN |
367 | int ubifs_setxattr(struct dentry *dentry, const char *name, |
368 | const void *value, size_t size, int flags) | |
369 | { | |
370 | dbg_gen("xattr '%s', host ino %lu ('%pd'), size %zd", | |
2b0143b5 | 371 | name, d_inode(dentry)->i_ino, dentry, size); |
895d9db2 | 372 | |
2b0143b5 | 373 | return setxattr(d_inode(dentry), name, value, size, flags); |
895d9db2 SN |
374 | } |
375 | ||
1e51764a AB |
376 | ssize_t ubifs_getxattr(struct dentry *dentry, const char *name, void *buf, |
377 | size_t size) | |
378 | { | |
2b0143b5 | 379 | struct inode *inode, *host = d_inode(dentry); |
1e51764a | 380 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 381 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
382 | struct ubifs_inode *ui; |
383 | struct ubifs_dent_node *xent; | |
384 | union ubifs_key key; | |
385 | int err; | |
386 | ||
4cb2a01d AV |
387 | dbg_gen("xattr '%s', ino %lu ('%pd'), buf size %zd", name, |
388 | host->i_ino, dentry, size); | |
1e51764a AB |
389 | |
390 | err = check_namespace(&nm); | |
391 | if (err < 0) | |
392 | return err; | |
393 | ||
394 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
395 | if (!xent) | |
396 | return -ENOMEM; | |
397 | ||
1e51764a AB |
398 | xent_key_init(c, &key, host->i_ino, &nm); |
399 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
400 | if (err) { | |
401 | if (err == -ENOENT) | |
402 | err = -ENODATA; | |
403 | goto out_unlock; | |
404 | } | |
405 | ||
406 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
407 | if (IS_ERR(inode)) { | |
408 | err = PTR_ERR(inode); | |
409 | goto out_unlock; | |
410 | } | |
411 | ||
412 | ui = ubifs_inode(inode); | |
413 | ubifs_assert(inode->i_size == ui->data_len); | |
414 | ubifs_assert(ubifs_inode(host)->xattr_size > ui->data_len); | |
415 | ||
ab92a20b | 416 | mutex_lock(&ui->ui_mutex); |
1e51764a AB |
417 | if (buf) { |
418 | /* If @buf is %NULL we are supposed to return the length */ | |
419 | if (ui->data_len > size) { | |
235c362b | 420 | ubifs_err(c, "buffer size %zd, xattr len %d", |
a6aae4dd | 421 | size, ui->data_len); |
1e51764a AB |
422 | err = -ERANGE; |
423 | goto out_iput; | |
424 | } | |
425 | ||
426 | memcpy(buf, ui->data, ui->data_len); | |
427 | } | |
428 | err = ui->data_len; | |
429 | ||
430 | out_iput: | |
ab92a20b | 431 | mutex_unlock(&ui->ui_mutex); |
1e51764a AB |
432 | iput(inode); |
433 | out_unlock: | |
1e51764a AB |
434 | kfree(xent); |
435 | return err; | |
436 | } | |
437 | ||
438 | ssize_t ubifs_listxattr(struct dentry *dentry, char *buffer, size_t size) | |
439 | { | |
440 | union ubifs_key key; | |
2b0143b5 | 441 | struct inode *host = d_inode(dentry); |
1e51764a AB |
442 | struct ubifs_info *c = host->i_sb->s_fs_info; |
443 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
444 | struct ubifs_dent_node *xent, *pxent = NULL; | |
445 | int err, len, written = 0; | |
446 | struct qstr nm = { .name = NULL }; | |
447 | ||
4cb2a01d AV |
448 | dbg_gen("ino %lu ('%pd'), buffer size %zd", host->i_ino, |
449 | dentry, size); | |
1e51764a AB |
450 | |
451 | len = host_ui->xattr_names + host_ui->xattr_cnt; | |
452 | if (!buffer) | |
453 | /* | |
454 | * We should return the minimum buffer size which will fit a | |
455 | * null-terminated list of all the extended attribute names. | |
456 | */ | |
457 | return len; | |
458 | ||
459 | if (len > size) | |
460 | return -ERANGE; | |
461 | ||
462 | lowest_xent_key(c, &key, host->i_ino); | |
1e51764a AB |
463 | while (1) { |
464 | int type; | |
465 | ||
466 | xent = ubifs_tnc_next_ent(c, &key, &nm); | |
8d47aef4 | 467 | if (IS_ERR(xent)) { |
1e51764a AB |
468 | err = PTR_ERR(xent); |
469 | break; | |
470 | } | |
471 | ||
472 | nm.name = xent->name; | |
473 | nm.len = le16_to_cpu(xent->nlen); | |
474 | ||
475 | type = check_namespace(&nm); | |
476 | if (unlikely(type < 0)) { | |
477 | err = type; | |
478 | break; | |
479 | } | |
480 | ||
481 | /* Show trusted namespace only for "power" users */ | |
482 | if (type != TRUSTED_XATTR || capable(CAP_SYS_ADMIN)) { | |
483 | memcpy(buffer + written, nm.name, nm.len + 1); | |
484 | written += nm.len + 1; | |
485 | } | |
486 | ||
487 | kfree(pxent); | |
488 | pxent = xent; | |
489 | key_read(c, &xent->key, &key); | |
490 | } | |
1e51764a AB |
491 | |
492 | kfree(pxent); | |
493 | if (err != -ENOENT) { | |
235c362b | 494 | ubifs_err(c, "cannot find next direntry, error %d", err); |
1e51764a AB |
495 | return err; |
496 | } | |
497 | ||
498 | ubifs_assert(written <= size); | |
499 | return written; | |
500 | } | |
501 | ||
502 | static int remove_xattr(struct ubifs_info *c, struct inode *host, | |
503 | struct inode *inode, const struct qstr *nm) | |
504 | { | |
505 | int err; | |
506 | struct ubifs_inode *host_ui = ubifs_inode(host); | |
507 | struct ubifs_inode *ui = ubifs_inode(inode); | |
5acd6ff8 ZS |
508 | struct ubifs_budget_req req = { .dirtied_ino = 2, .mod_dent = 1, |
509 | .dirtied_ino_d = ALIGN(host_ui->data_len, 8) }; | |
1e51764a AB |
510 | |
511 | ubifs_assert(ui->data_len == inode->i_size); | |
512 | ||
513 | err = ubifs_budget_space(c, &req); | |
514 | if (err) | |
515 | return err; | |
516 | ||
517 | mutex_lock(&host_ui->ui_mutex); | |
518 | host->i_ctime = ubifs_current_time(host); | |
519 | host_ui->xattr_cnt -= 1; | |
520 | host_ui->xattr_size -= CALC_DENT_SIZE(nm->len); | |
521 | host_ui->xattr_size -= CALC_XATTR_BYTES(ui->data_len); | |
522 | host_ui->xattr_names -= nm->len; | |
523 | ||
524 | err = ubifs_jnl_delete_xattr(c, host, inode, nm); | |
525 | if (err) | |
526 | goto out_cancel; | |
527 | mutex_unlock(&host_ui->ui_mutex); | |
528 | ||
529 | ubifs_release_budget(c, &req); | |
530 | return 0; | |
531 | ||
532 | out_cancel: | |
533 | host_ui->xattr_cnt += 1; | |
534 | host_ui->xattr_size += CALC_DENT_SIZE(nm->len); | |
535 | host_ui->xattr_size += CALC_XATTR_BYTES(ui->data_len); | |
536 | mutex_unlock(&host_ui->ui_mutex); | |
537 | ubifs_release_budget(c, &req); | |
538 | make_bad_inode(inode); | |
539 | return err; | |
540 | } | |
541 | ||
542 | int ubifs_removexattr(struct dentry *dentry, const char *name) | |
543 | { | |
2b0143b5 | 544 | struct inode *inode, *host = d_inode(dentry); |
1e51764a | 545 | struct ubifs_info *c = host->i_sb->s_fs_info; |
26fe5750 | 546 | struct qstr nm = QSTR_INIT(name, strlen(name)); |
1e51764a AB |
547 | struct ubifs_dent_node *xent; |
548 | union ubifs_key key; | |
549 | int err; | |
550 | ||
4cb2a01d AV |
551 | dbg_gen("xattr '%s', ino %lu ('%pd')", name, |
552 | host->i_ino, dentry); | |
5955102c | 553 | ubifs_assert(inode_is_locked(host)); |
1e51764a AB |
554 | |
555 | err = check_namespace(&nm); | |
556 | if (err < 0) | |
557 | return err; | |
558 | ||
559 | xent = kmalloc(UBIFS_MAX_XENT_NODE_SZ, GFP_NOFS); | |
560 | if (!xent) | |
561 | return -ENOMEM; | |
562 | ||
563 | xent_key_init(c, &key, host->i_ino, &nm); | |
564 | err = ubifs_tnc_lookup_nm(c, &key, xent, &nm); | |
565 | if (err) { | |
566 | if (err == -ENOENT) | |
567 | err = -ENODATA; | |
568 | goto out_free; | |
569 | } | |
570 | ||
571 | inode = iget_xattr(c, le64_to_cpu(xent->inum)); | |
572 | if (IS_ERR(inode)) { | |
573 | err = PTR_ERR(inode); | |
574 | goto out_free; | |
575 | } | |
576 | ||
577 | ubifs_assert(inode->i_nlink == 1); | |
6d6b77f1 | 578 | clear_nlink(inode); |
1e51764a AB |
579 | err = remove_xattr(c, host, inode, &nm); |
580 | if (err) | |
bfe86848 | 581 | set_nlink(inode, 1); |
1e51764a AB |
582 | |
583 | /* If @i_nlink is 0, 'iput()' will delete the inode */ | |
584 | iput(inode); | |
585 | ||
586 | out_free: | |
587 | kfree(xent); | |
588 | return err; | |
589 | } | |
d7f0b70d | 590 | |
d7f0b70d SN |
591 | static int init_xattrs(struct inode *inode, const struct xattr *xattr_array, |
592 | void *fs_info) | |
593 | { | |
594 | const struct xattr *xattr; | |
595 | char *name; | |
596 | int err = 0; | |
597 | ||
598 | for (xattr = xattr_array; xattr->name != NULL; xattr++) { | |
599 | name = kmalloc(XATTR_SECURITY_PREFIX_LEN + | |
600 | strlen(xattr->name) + 1, GFP_NOFS); | |
601 | if (!name) { | |
602 | err = -ENOMEM; | |
603 | break; | |
604 | } | |
605 | strcpy(name, XATTR_SECURITY_PREFIX); | |
606 | strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); | |
607 | err = setxattr(inode, name, xattr->value, xattr->value_len, 0); | |
608 | kfree(name); | |
609 | if (err < 0) | |
610 | break; | |
611 | } | |
612 | ||
613 | return err; | |
614 | } | |
615 | ||
616 | int ubifs_init_security(struct inode *dentry, struct inode *inode, | |
617 | const struct qstr *qstr) | |
618 | { | |
619 | int err; | |
620 | ||
d7f0b70d SN |
621 | err = security_inode_init_security(inode, dentry, qstr, |
622 | &init_xattrs, 0); | |
235c362b SY |
623 | if (err) { |
624 | struct ubifs_info *c = dentry->i_sb->s_fs_info; | |
625 | ubifs_err(c, "cannot initialize security for inode %lu, error %d", | |
fee1756d | 626 | inode->i_ino, err); |
235c362b | 627 | } |
d7f0b70d SN |
628 | return err; |
629 | } |