Commit | Line | Data |
---|---|---|
77b14db5 EB |
1 | /* |
2 | * /proc/sys support | |
3 | */ | |
1e0edd3f | 4 | #include <linux/init.h> |
77b14db5 | 5 | #include <linux/sysctl.h> |
f1ecf068 | 6 | #include <linux/poll.h> |
77b14db5 | 7 | #include <linux/proc_fs.h> |
87ebdc00 | 8 | #include <linux/printk.h> |
77b14db5 | 9 | #include <linux/security.h> |
40401530 | 10 | #include <linux/sched.h> |
34286d66 | 11 | #include <linux/namei.h> |
40401530 | 12 | #include <linux/mm.h> |
1f87f0b5 | 13 | #include <linux/module.h> |
77b14db5 EB |
14 | #include "internal.h" |
15 | ||
d72f71eb | 16 | static const struct dentry_operations proc_sys_dentry_operations; |
77b14db5 | 17 | static const struct file_operations proc_sys_file_operations; |
03a44825 | 18 | static const struct inode_operations proc_sys_inode_operations; |
9043476f AV |
19 | static const struct file_operations proc_sys_dir_file_operations; |
20 | static const struct inode_operations proc_sys_dir_operations; | |
77b14db5 | 21 | |
f9bd6733 EB |
22 | /* Support for permanently empty directories */ |
23 | ||
24 | struct ctl_table sysctl_mount_point[] = { | |
25 | { } | |
26 | }; | |
27 | ||
28 | static bool is_empty_dir(struct ctl_table_header *head) | |
29 | { | |
30 | return head->ctl_table[0].child == sysctl_mount_point; | |
31 | } | |
32 | ||
33 | static void set_empty_dir(struct ctl_dir *dir) | |
34 | { | |
35 | dir->header.ctl_table[0].child = sysctl_mount_point; | |
36 | } | |
37 | ||
38 | static void clear_empty_dir(struct ctl_dir *dir) | |
39 | ||
40 | { | |
41 | dir->header.ctl_table[0].child = NULL; | |
42 | } | |
43 | ||
f1ecf068 LDM |
44 | void proc_sys_poll_notify(struct ctl_table_poll *poll) |
45 | { | |
46 | if (!poll) | |
47 | return; | |
48 | ||
49 | atomic_inc(&poll->event); | |
50 | wake_up_interruptible(&poll->wait); | |
51 | } | |
52 | ||
a194558e EB |
53 | static struct ctl_table root_table[] = { |
54 | { | |
55 | .procname = "", | |
7ec66d06 | 56 | .mode = S_IFDIR|S_IRUGO|S_IXUGO, |
a194558e EB |
57 | }, |
58 | { } | |
59 | }; | |
0e47c99d | 60 | static struct ctl_table_root sysctl_table_root = { |
0e47c99d | 61 | .default_set.dir.header = { |
7ec66d06 EB |
62 | {{.count = 1, |
63 | .nreg = 1, | |
ac13ac6f | 64 | .ctl_table = root_table }}, |
0e47c99d | 65 | .ctl_table_arg = root_table, |
7ec66d06 EB |
66 | .root = &sysctl_table_root, |
67 | .set = &sysctl_table_root.default_set, | |
68 | }, | |
1f87f0b5 | 69 | }; |
1f87f0b5 EB |
70 | |
71 | static DEFINE_SPINLOCK(sysctl_lock); | |
72 | ||
7ec66d06 | 73 | static void drop_sysctl_table(struct ctl_table_header *header); |
0e47c99d EB |
74 | static int sysctl_follow_link(struct ctl_table_header **phead, |
75 | struct ctl_table **pentry, struct nsproxy *namespaces); | |
76 | static int insert_links(struct ctl_table_header *head); | |
77 | static void put_links(struct ctl_table_header *header); | |
7ec66d06 | 78 | |
6980128f EB |
79 | static void sysctl_print_dir(struct ctl_dir *dir) |
80 | { | |
81 | if (dir->header.parent) | |
82 | sysctl_print_dir(dir->header.parent); | |
87ebdc00 | 83 | pr_cont("%s/", dir->header.ctl_table[0].procname); |
6980128f EB |
84 | } |
85 | ||
076c3eed EB |
86 | static int namecmp(const char *name1, int len1, const char *name2, int len2) |
87 | { | |
88 | int minlen; | |
89 | int cmp; | |
90 | ||
91 | minlen = len1; | |
92 | if (minlen > len2) | |
93 | minlen = len2; | |
94 | ||
95 | cmp = memcmp(name1, name2, minlen); | |
96 | if (cmp == 0) | |
97 | cmp = len1 - len2; | |
98 | return cmp; | |
99 | } | |
100 | ||
60f126d9 | 101 | /* Called under sysctl_lock */ |
076c3eed | 102 | static struct ctl_table *find_entry(struct ctl_table_header **phead, |
0e47c99d | 103 | struct ctl_dir *dir, const char *name, int namelen) |
076c3eed EB |
104 | { |
105 | struct ctl_table_header *head; | |
106 | struct ctl_table *entry; | |
ac13ac6f | 107 | struct rb_node *node = dir->root.rb_node; |
076c3eed | 108 | |
ac13ac6f EB |
109 | while (node) |
110 | { | |
111 | struct ctl_node *ctl_node; | |
112 | const char *procname; | |
113 | int cmp; | |
114 | ||
115 | ctl_node = rb_entry(node, struct ctl_node, node); | |
116 | head = ctl_node->header; | |
117 | entry = &head->ctl_table[ctl_node - head->node]; | |
118 | procname = entry->procname; | |
119 | ||
120 | cmp = namecmp(name, namelen, procname, strlen(procname)); | |
121 | if (cmp < 0) | |
122 | node = node->rb_left; | |
123 | else if (cmp > 0) | |
124 | node = node->rb_right; | |
125 | else { | |
126 | *phead = head; | |
127 | return entry; | |
076c3eed EB |
128 | } |
129 | } | |
130 | return NULL; | |
131 | } | |
132 | ||
ac13ac6f EB |
133 | static int insert_entry(struct ctl_table_header *head, struct ctl_table *entry) |
134 | { | |
135 | struct rb_node *node = &head->node[entry - head->ctl_table].node; | |
136 | struct rb_node **p = &head->parent->root.rb_node; | |
137 | struct rb_node *parent = NULL; | |
138 | const char *name = entry->procname; | |
139 | int namelen = strlen(name); | |
140 | ||
141 | while (*p) { | |
142 | struct ctl_table_header *parent_head; | |
143 | struct ctl_table *parent_entry; | |
144 | struct ctl_node *parent_node; | |
145 | const char *parent_name; | |
146 | int cmp; | |
147 | ||
148 | parent = *p; | |
149 | parent_node = rb_entry(parent, struct ctl_node, node); | |
150 | parent_head = parent_node->header; | |
151 | parent_entry = &parent_head->ctl_table[parent_node - parent_head->node]; | |
152 | parent_name = parent_entry->procname; | |
153 | ||
154 | cmp = namecmp(name, namelen, parent_name, strlen(parent_name)); | |
155 | if (cmp < 0) | |
156 | p = &(*p)->rb_left; | |
157 | else if (cmp > 0) | |
158 | p = &(*p)->rb_right; | |
159 | else { | |
87ebdc00 | 160 | pr_err("sysctl duplicate entry: "); |
ac13ac6f | 161 | sysctl_print_dir(head->parent); |
87ebdc00 | 162 | pr_cont("/%s\n", entry->procname); |
ac13ac6f EB |
163 | return -EEXIST; |
164 | } | |
165 | } | |
166 | ||
167 | rb_link_node(node, parent, p); | |
ea5272f5 | 168 | rb_insert_color(node, &head->parent->root); |
ac13ac6f EB |
169 | return 0; |
170 | } | |
171 | ||
172 | static void erase_entry(struct ctl_table_header *head, struct ctl_table *entry) | |
173 | { | |
174 | struct rb_node *node = &head->node[entry - head->ctl_table].node; | |
175 | ||
176 | rb_erase(node, &head->parent->root); | |
177 | } | |
178 | ||
e0d04529 EB |
179 | static void init_header(struct ctl_table_header *head, |
180 | struct ctl_table_root *root, struct ctl_table_set *set, | |
ac13ac6f | 181 | struct ctl_node *node, struct ctl_table *table) |
e0d04529 | 182 | { |
7ec66d06 | 183 | head->ctl_table = table; |
e0d04529 | 184 | head->ctl_table_arg = table; |
e0d04529 EB |
185 | head->used = 0; |
186 | head->count = 1; | |
187 | head->nreg = 1; | |
188 | head->unregistering = NULL; | |
189 | head->root = root; | |
190 | head->set = set; | |
191 | head->parent = NULL; | |
ac13ac6f EB |
192 | head->node = node; |
193 | if (node) { | |
194 | struct ctl_table *entry; | |
4c199a93 | 195 | for (entry = table; entry->procname; entry++, node++) |
ac13ac6f | 196 | node->header = head; |
ac13ac6f | 197 | } |
e0d04529 EB |
198 | } |
199 | ||
8425d6aa EB |
200 | static void erase_header(struct ctl_table_header *head) |
201 | { | |
ac13ac6f EB |
202 | struct ctl_table *entry; |
203 | for (entry = head->ctl_table; entry->procname; entry++) | |
204 | erase_entry(head, entry); | |
8425d6aa EB |
205 | } |
206 | ||
0e47c99d | 207 | static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header) |
8425d6aa | 208 | { |
ac13ac6f | 209 | struct ctl_table *entry; |
0e47c99d EB |
210 | int err; |
211 | ||
f9bd6733 EB |
212 | /* Is this a permanently empty directory? */ |
213 | if (is_empty_dir(&dir->header)) | |
214 | return -EROFS; | |
215 | ||
216 | /* Am I creating a permanently empty directory? */ | |
217 | if (header->ctl_table == sysctl_mount_point) { | |
218 | if (!RB_EMPTY_ROOT(&dir->root)) | |
219 | return -EINVAL; | |
220 | set_empty_dir(dir); | |
221 | } | |
222 | ||
0e47c99d | 223 | dir->header.nreg++; |
7ec66d06 | 224 | header->parent = dir; |
0e47c99d EB |
225 | err = insert_links(header); |
226 | if (err) | |
227 | goto fail_links; | |
ac13ac6f EB |
228 | for (entry = header->ctl_table; entry->procname; entry++) { |
229 | err = insert_entry(header, entry); | |
230 | if (err) | |
231 | goto fail; | |
232 | } | |
0e47c99d | 233 | return 0; |
ac13ac6f EB |
234 | fail: |
235 | erase_header(header); | |
236 | put_links(header); | |
0e47c99d | 237 | fail_links: |
f9bd6733 EB |
238 | if (header->ctl_table == sysctl_mount_point) |
239 | clear_empty_dir(dir); | |
0e47c99d EB |
240 | header->parent = NULL; |
241 | drop_sysctl_table(&dir->header); | |
242 | return err; | |
8425d6aa EB |
243 | } |
244 | ||
1f87f0b5 EB |
245 | /* called under sysctl_lock */ |
246 | static int use_table(struct ctl_table_header *p) | |
247 | { | |
248 | if (unlikely(p->unregistering)) | |
249 | return 0; | |
250 | p->used++; | |
251 | return 1; | |
252 | } | |
253 | ||
254 | /* called under sysctl_lock */ | |
255 | static void unuse_table(struct ctl_table_header *p) | |
256 | { | |
257 | if (!--p->used) | |
258 | if (unlikely(p->unregistering)) | |
259 | complete(p->unregistering); | |
260 | } | |
261 | ||
262 | /* called under sysctl_lock, will reacquire if has to wait */ | |
263 | static void start_unregistering(struct ctl_table_header *p) | |
264 | { | |
265 | /* | |
266 | * if p->used is 0, nobody will ever touch that entry again; | |
267 | * we'll eliminate all paths to it before dropping sysctl_lock | |
268 | */ | |
269 | if (unlikely(p->used)) { | |
270 | struct completion wait; | |
271 | init_completion(&wait); | |
272 | p->unregistering = &wait; | |
273 | spin_unlock(&sysctl_lock); | |
274 | wait_for_completion(&wait); | |
275 | spin_lock(&sysctl_lock); | |
276 | } else { | |
277 | /* anything non-NULL; we'll never dereference it */ | |
278 | p->unregistering = ERR_PTR(-EINVAL); | |
279 | } | |
280 | /* | |
281 | * do not remove from the list until nobody holds it; walking the | |
282 | * list in do_sysctl() relies on that. | |
283 | */ | |
8425d6aa | 284 | erase_header(p); |
1f87f0b5 EB |
285 | } |
286 | ||
287 | static void sysctl_head_get(struct ctl_table_header *head) | |
288 | { | |
289 | spin_lock(&sysctl_lock); | |
290 | head->count++; | |
291 | spin_unlock(&sysctl_lock); | |
292 | } | |
293 | ||
294 | void sysctl_head_put(struct ctl_table_header *head) | |
295 | { | |
296 | spin_lock(&sysctl_lock); | |
297 | if (!--head->count) | |
298 | kfree_rcu(head, rcu); | |
299 | spin_unlock(&sysctl_lock); | |
300 | } | |
301 | ||
302 | static struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head) | |
303 | { | |
ab4a1f24 | 304 | BUG_ON(!head); |
1f87f0b5 EB |
305 | spin_lock(&sysctl_lock); |
306 | if (!use_table(head)) | |
307 | head = ERR_PTR(-ENOENT); | |
308 | spin_unlock(&sysctl_lock); | |
309 | return head; | |
310 | } | |
311 | ||
312 | static void sysctl_head_finish(struct ctl_table_header *head) | |
313 | { | |
314 | if (!head) | |
315 | return; | |
316 | spin_lock(&sysctl_lock); | |
317 | unuse_table(head); | |
318 | spin_unlock(&sysctl_lock); | |
319 | } | |
320 | ||
321 | static struct ctl_table_set * | |
322 | lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces) | |
323 | { | |
324 | struct ctl_table_set *set = &root->default_set; | |
325 | if (root->lookup) | |
326 | set = root->lookup(root, namespaces); | |
327 | return set; | |
328 | } | |
329 | ||
076c3eed | 330 | static struct ctl_table *lookup_entry(struct ctl_table_header **phead, |
7ec66d06 | 331 | struct ctl_dir *dir, |
076c3eed EB |
332 | const char *name, int namelen) |
333 | { | |
334 | struct ctl_table_header *head; | |
335 | struct ctl_table *entry; | |
076c3eed EB |
336 | |
337 | spin_lock(&sysctl_lock); | |
0e47c99d EB |
338 | entry = find_entry(&head, dir, name, namelen); |
339 | if (entry && use_table(head)) | |
340 | *phead = head; | |
341 | else | |
342 | entry = NULL; | |
076c3eed EB |
343 | spin_unlock(&sysctl_lock); |
344 | return entry; | |
345 | } | |
346 | ||
ac13ac6f | 347 | static struct ctl_node *first_usable_entry(struct rb_node *node) |
1f87f0b5 | 348 | { |
ac13ac6f | 349 | struct ctl_node *ctl_node; |
1f87f0b5 | 350 | |
ac13ac6f EB |
351 | for (;node; node = rb_next(node)) { |
352 | ctl_node = rb_entry(node, struct ctl_node, node); | |
353 | if (use_table(ctl_node->header)) | |
354 | return ctl_node; | |
1f87f0b5 | 355 | } |
1f87f0b5 EB |
356 | return NULL; |
357 | } | |
358 | ||
7ec66d06 | 359 | static void first_entry(struct ctl_dir *dir, |
6a75ce16 EB |
360 | struct ctl_table_header **phead, struct ctl_table **pentry) |
361 | { | |
ac13ac6f | 362 | struct ctl_table_header *head = NULL; |
7ec66d06 | 363 | struct ctl_table *entry = NULL; |
ac13ac6f | 364 | struct ctl_node *ctl_node; |
6a75ce16 EB |
365 | |
366 | spin_lock(&sysctl_lock); | |
ac13ac6f | 367 | ctl_node = first_usable_entry(rb_first(&dir->root)); |
6a75ce16 | 368 | spin_unlock(&sysctl_lock); |
ac13ac6f EB |
369 | if (ctl_node) { |
370 | head = ctl_node->header; | |
371 | entry = &head->ctl_table[ctl_node - head->node]; | |
372 | } | |
6a75ce16 EB |
373 | *phead = head; |
374 | *pentry = entry; | |
375 | } | |
376 | ||
7ec66d06 | 377 | static void next_entry(struct ctl_table_header **phead, struct ctl_table **pentry) |
1f87f0b5 | 378 | { |
6a75ce16 EB |
379 | struct ctl_table_header *head = *phead; |
380 | struct ctl_table *entry = *pentry; | |
ac13ac6f | 381 | struct ctl_node *ctl_node = &head->node[entry - head->ctl_table]; |
6a75ce16 | 382 | |
ac13ac6f EB |
383 | spin_lock(&sysctl_lock); |
384 | unuse_table(head); | |
385 | ||
386 | ctl_node = first_usable_entry(rb_next(&ctl_node->node)); | |
387 | spin_unlock(&sysctl_lock); | |
388 | head = NULL; | |
389 | if (ctl_node) { | |
390 | head = ctl_node->header; | |
391 | entry = &head->ctl_table[ctl_node - head->node]; | |
6a75ce16 EB |
392 | } |
393 | *phead = head; | |
394 | *pentry = entry; | |
1f87f0b5 EB |
395 | } |
396 | ||
397 | void register_sysctl_root(struct ctl_table_root *root) | |
398 | { | |
1f87f0b5 EB |
399 | } |
400 | ||
401 | /* | |
402 | * sysctl_perm does NOT grant the superuser all rights automatically, because | |
403 | * some sysctl variables are readonly even to root. | |
404 | */ | |
405 | ||
406 | static int test_perm(int mode, int op) | |
407 | { | |
091bd3ea | 408 | if (uid_eq(current_euid(), GLOBAL_ROOT_UID)) |
1f87f0b5 | 409 | mode >>= 6; |
091bd3ea | 410 | else if (in_egroup_p(GLOBAL_ROOT_GID)) |
1f87f0b5 EB |
411 | mode >>= 3; |
412 | if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0) | |
413 | return 0; | |
414 | return -EACCES; | |
415 | } | |
416 | ||
73f7ef43 | 417 | static int sysctl_perm(struct ctl_table_header *head, struct ctl_table *table, int op) |
1f87f0b5 | 418 | { |
73f7ef43 | 419 | struct ctl_table_root *root = head->root; |
1f87f0b5 EB |
420 | int mode; |
421 | ||
422 | if (root->permissions) | |
73f7ef43 | 423 | mode = root->permissions(head, table); |
1f87f0b5 EB |
424 | else |
425 | mode = table->mode; | |
426 | ||
427 | return test_perm(mode, op); | |
428 | } | |
429 | ||
9043476f AV |
430 | static struct inode *proc_sys_make_inode(struct super_block *sb, |
431 | struct ctl_table_header *head, struct ctl_table *table) | |
77b14db5 EB |
432 | { |
433 | struct inode *inode; | |
9043476f | 434 | struct proc_inode *ei; |
77b14db5 | 435 | |
9043476f | 436 | inode = new_inode(sb); |
77b14db5 EB |
437 | if (!inode) |
438 | goto out; | |
439 | ||
85fe4025 CH |
440 | inode->i_ino = get_next_ino(); |
441 | ||
9043476f | 442 | sysctl_head_get(head); |
77b14db5 | 443 | ei = PROC_I(inode); |
9043476f AV |
444 | ei->sysctl = head; |
445 | ei->sysctl_entry = table; | |
446 | ||
77b14db5 | 447 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; |
9043476f | 448 | inode->i_mode = table->mode; |
7ec66d06 | 449 | if (!S_ISDIR(table->mode)) { |
9043476f AV |
450 | inode->i_mode |= S_IFREG; |
451 | inode->i_op = &proc_sys_inode_operations; | |
452 | inode->i_fop = &proc_sys_file_operations; | |
453 | } else { | |
454 | inode->i_mode |= S_IFDIR; | |
9043476f AV |
455 | inode->i_op = &proc_sys_dir_operations; |
456 | inode->i_fop = &proc_sys_dir_file_operations; | |
f9bd6733 EB |
457 | if (is_empty_dir(head)) |
458 | make_empty_dir_inode(inode); | |
9043476f | 459 | } |
77b14db5 EB |
460 | out: |
461 | return inode; | |
462 | } | |
463 | ||
81324364 | 464 | static struct ctl_table_header *grab_header(struct inode *inode) |
77b14db5 | 465 | { |
3cc3e046 EB |
466 | struct ctl_table_header *head = PROC_I(inode)->sysctl; |
467 | if (!head) | |
0e47c99d | 468 | head = &sysctl_table_root.default_set.dir.header; |
3cc3e046 | 469 | return sysctl_head_grab(head); |
9043476f | 470 | } |
77b14db5 | 471 | |
9043476f | 472 | static struct dentry *proc_sys_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 473 | unsigned int flags) |
9043476f AV |
474 | { |
475 | struct ctl_table_header *head = grab_header(dir); | |
9043476f | 476 | struct ctl_table_header *h = NULL; |
dc12e909 | 477 | const struct qstr *name = &dentry->d_name; |
9043476f AV |
478 | struct ctl_table *p; |
479 | struct inode *inode; | |
480 | struct dentry *err = ERR_PTR(-ENOENT); | |
7ec66d06 | 481 | struct ctl_dir *ctl_dir; |
0e47c99d | 482 | int ret; |
77b14db5 | 483 | |
9043476f AV |
484 | if (IS_ERR(head)) |
485 | return ERR_CAST(head); | |
77b14db5 | 486 | |
7ec66d06 | 487 | ctl_dir = container_of(head, struct ctl_dir, header); |
77b14db5 | 488 | |
7ec66d06 | 489 | p = lookup_entry(&h, ctl_dir, name->name, name->len); |
9043476f | 490 | if (!p) |
77b14db5 EB |
491 | goto out; |
492 | ||
4e757320 EB |
493 | if (S_ISLNK(p->mode)) { |
494 | ret = sysctl_follow_link(&h, &p, current->nsproxy); | |
495 | err = ERR_PTR(ret); | |
496 | if (ret) | |
497 | goto out; | |
498 | } | |
0e47c99d | 499 | |
77b14db5 | 500 | err = ERR_PTR(-ENOMEM); |
9043476f | 501 | inode = proc_sys_make_inode(dir->i_sb, h ? h : head, p); |
77b14db5 EB |
502 | if (!inode) |
503 | goto out; | |
504 | ||
505 | err = NULL; | |
fb045adb | 506 | d_set_d_op(dentry, &proc_sys_dentry_operations); |
77b14db5 EB |
507 | d_add(dentry, inode); |
508 | ||
509 | out: | |
6bf61045 FR |
510 | if (h) |
511 | sysctl_head_finish(h); | |
77b14db5 EB |
512 | sysctl_head_finish(head); |
513 | return err; | |
514 | } | |
515 | ||
7708bfb1 PE |
516 | static ssize_t proc_sys_call_handler(struct file *filp, void __user *buf, |
517 | size_t count, loff_t *ppos, int write) | |
77b14db5 | 518 | { |
496ad9aa | 519 | struct inode *inode = file_inode(filp); |
9043476f AV |
520 | struct ctl_table_header *head = grab_header(inode); |
521 | struct ctl_table *table = PROC_I(inode)->sysctl_entry; | |
2a2da53b DH |
522 | ssize_t error; |
523 | size_t res; | |
77b14db5 | 524 | |
9043476f AV |
525 | if (IS_ERR(head)) |
526 | return PTR_ERR(head); | |
77b14db5 EB |
527 | |
528 | /* | |
529 | * At this point we know that the sysctl was not unregistered | |
530 | * and won't be until we finish. | |
531 | */ | |
532 | error = -EPERM; | |
73f7ef43 | 533 | if (sysctl_perm(head, table, write ? MAY_WRITE : MAY_READ)) |
77b14db5 EB |
534 | goto out; |
535 | ||
9043476f AV |
536 | /* if that can happen at all, it should be -EINVAL, not -EISDIR */ |
537 | error = -EINVAL; | |
538 | if (!table->proc_handler) | |
539 | goto out; | |
540 | ||
77b14db5 EB |
541 | /* careful: calling conventions are nasty here */ |
542 | res = count; | |
8d65af78 | 543 | error = table->proc_handler(table, write, buf, &res, ppos); |
77b14db5 EB |
544 | if (!error) |
545 | error = res; | |
546 | out: | |
547 | sysctl_head_finish(head); | |
548 | ||
549 | return error; | |
550 | } | |
551 | ||
7708bfb1 | 552 | static ssize_t proc_sys_read(struct file *filp, char __user *buf, |
77b14db5 EB |
553 | size_t count, loff_t *ppos) |
554 | { | |
7708bfb1 PE |
555 | return proc_sys_call_handler(filp, (void __user *)buf, count, ppos, 0); |
556 | } | |
77b14db5 | 557 | |
7708bfb1 PE |
558 | static ssize_t proc_sys_write(struct file *filp, const char __user *buf, |
559 | size_t count, loff_t *ppos) | |
560 | { | |
561 | return proc_sys_call_handler(filp, (void __user *)buf, count, ppos, 1); | |
77b14db5 EB |
562 | } |
563 | ||
f1ecf068 LDM |
564 | static int proc_sys_open(struct inode *inode, struct file *filp) |
565 | { | |
4e474a00 | 566 | struct ctl_table_header *head = grab_header(inode); |
f1ecf068 LDM |
567 | struct ctl_table *table = PROC_I(inode)->sysctl_entry; |
568 | ||
4e474a00 LDM |
569 | /* sysctl was unregistered */ |
570 | if (IS_ERR(head)) | |
571 | return PTR_ERR(head); | |
572 | ||
f1ecf068 LDM |
573 | if (table->poll) |
574 | filp->private_data = proc_sys_poll_event(table->poll); | |
575 | ||
4e474a00 LDM |
576 | sysctl_head_finish(head); |
577 | ||
f1ecf068 LDM |
578 | return 0; |
579 | } | |
580 | ||
581 | static unsigned int proc_sys_poll(struct file *filp, poll_table *wait) | |
582 | { | |
496ad9aa | 583 | struct inode *inode = file_inode(filp); |
4e474a00 | 584 | struct ctl_table_header *head = grab_header(inode); |
f1ecf068 | 585 | struct ctl_table *table = PROC_I(inode)->sysctl_entry; |
f1ecf068 | 586 | unsigned int ret = DEFAULT_POLLMASK; |
4e474a00 LDM |
587 | unsigned long event; |
588 | ||
589 | /* sysctl was unregistered */ | |
590 | if (IS_ERR(head)) | |
591 | return POLLERR | POLLHUP; | |
f1ecf068 LDM |
592 | |
593 | if (!table->proc_handler) | |
594 | goto out; | |
595 | ||
596 | if (!table->poll) | |
597 | goto out; | |
598 | ||
4e474a00 | 599 | event = (unsigned long)filp->private_data; |
f1ecf068 LDM |
600 | poll_wait(filp, &table->poll->wait, wait); |
601 | ||
602 | if (event != atomic_read(&table->poll->event)) { | |
603 | filp->private_data = proc_sys_poll_event(table->poll); | |
604 | ret = POLLIN | POLLRDNORM | POLLERR | POLLPRI; | |
605 | } | |
606 | ||
607 | out: | |
4e474a00 LDM |
608 | sysctl_head_finish(head); |
609 | ||
f1ecf068 LDM |
610 | return ret; |
611 | } | |
77b14db5 | 612 | |
f0c3b509 AV |
613 | static bool proc_sys_fill_cache(struct file *file, |
614 | struct dir_context *ctx, | |
9043476f AV |
615 | struct ctl_table_header *head, |
616 | struct ctl_table *table) | |
77b14db5 | 617 | { |
f0c3b509 | 618 | struct dentry *child, *dir = file->f_path.dentry; |
77b14db5 EB |
619 | struct inode *inode; |
620 | struct qstr qname; | |
621 | ino_t ino = 0; | |
622 | unsigned type = DT_UNKNOWN; | |
77b14db5 EB |
623 | |
624 | qname.name = table->procname; | |
625 | qname.len = strlen(table->procname); | |
8387ff25 | 626 | qname.hash = full_name_hash(dir, qname.name, qname.len); |
77b14db5 | 627 | |
77b14db5 EB |
628 | child = d_lookup(dir, &qname); |
629 | if (!child) { | |
76aab3ab AV |
630 | DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); |
631 | child = d_alloc_parallel(dir, &qname, &wq); | |
632 | if (IS_ERR(child)) | |
633 | return false; | |
634 | if (d_in_lookup(child)) { | |
9043476f AV |
635 | inode = proc_sys_make_inode(dir->d_sb, head, table); |
636 | if (!inode) { | |
76aab3ab | 637 | d_lookup_done(child); |
9043476f | 638 | dput(child); |
f0c3b509 | 639 | return false; |
77b14db5 | 640 | } |
76aab3ab AV |
641 | d_set_d_op(child, &proc_sys_dentry_operations); |
642 | d_add(child, inode); | |
77b14db5 EB |
643 | } |
644 | } | |
2b0143b5 | 645 | inode = d_inode(child); |
9043476f AV |
646 | ino = inode->i_ino; |
647 | type = inode->i_mode >> 12; | |
77b14db5 | 648 | dput(child); |
f0c3b509 | 649 | return dir_emit(ctx, qname.name, qname.len, ino, type); |
9043476f AV |
650 | } |
651 | ||
f0c3b509 AV |
652 | static bool proc_sys_link_fill_cache(struct file *file, |
653 | struct dir_context *ctx, | |
0e47c99d EB |
654 | struct ctl_table_header *head, |
655 | struct ctl_table *table) | |
656 | { | |
f0c3b509 | 657 | bool ret = true; |
0e47c99d EB |
658 | head = sysctl_head_grab(head); |
659 | ||
4e757320 EB |
660 | if (S_ISLNK(table->mode)) { |
661 | /* It is not an error if we can not follow the link ignore it */ | |
f0c3b509 | 662 | int err = sysctl_follow_link(&head, &table, current->nsproxy); |
4e757320 EB |
663 | if (err) |
664 | goto out; | |
665 | } | |
0e47c99d | 666 | |
f0c3b509 | 667 | ret = proc_sys_fill_cache(file, ctx, head, table); |
0e47c99d EB |
668 | out: |
669 | sysctl_head_finish(head); | |
670 | return ret; | |
671 | } | |
672 | ||
e5eea098 | 673 | static int scan(struct ctl_table_header *head, struct ctl_table *table, |
9043476f | 674 | unsigned long *pos, struct file *file, |
f0c3b509 | 675 | struct dir_context *ctx) |
9043476f | 676 | { |
f0c3b509 | 677 | bool res; |
9043476f | 678 | |
f0c3b509 AV |
679 | if ((*pos)++ < ctx->pos) |
680 | return true; | |
9043476f | 681 | |
0e47c99d | 682 | if (unlikely(S_ISLNK(table->mode))) |
f0c3b509 | 683 | res = proc_sys_link_fill_cache(file, ctx, head, table); |
0e47c99d | 684 | else |
f0c3b509 | 685 | res = proc_sys_fill_cache(file, ctx, head, table); |
9043476f | 686 | |
f0c3b509 AV |
687 | if (res) |
688 | ctx->pos = *pos; | |
9043476f | 689 | |
6a75ce16 | 690 | return res; |
77b14db5 EB |
691 | } |
692 | ||
f0c3b509 | 693 | static int proc_sys_readdir(struct file *file, struct dir_context *ctx) |
77b14db5 | 694 | { |
f0c3b509 | 695 | struct ctl_table_header *head = grab_header(file_inode(file)); |
9043476f | 696 | struct ctl_table_header *h = NULL; |
6a75ce16 | 697 | struct ctl_table *entry; |
7ec66d06 | 698 | struct ctl_dir *ctl_dir; |
77b14db5 | 699 | unsigned long pos; |
9043476f AV |
700 | |
701 | if (IS_ERR(head)) | |
702 | return PTR_ERR(head); | |
77b14db5 | 703 | |
7ec66d06 | 704 | ctl_dir = container_of(head, struct ctl_dir, header); |
77b14db5 | 705 | |
f0c3b509 AV |
706 | if (!dir_emit_dots(file, ctx)) |
707 | return 0; | |
708 | ||
77b14db5 EB |
709 | pos = 2; |
710 | ||
7ec66d06 | 711 | for (first_entry(ctl_dir, &h, &entry); h; next_entry(&h, &entry)) { |
f0c3b509 | 712 | if (!scan(h, entry, &pos, file, ctx)) { |
9043476f AV |
713 | sysctl_head_finish(h); |
714 | break; | |
77b14db5 EB |
715 | } |
716 | } | |
77b14db5 | 717 | sysctl_head_finish(head); |
f0c3b509 | 718 | return 0; |
77b14db5 EB |
719 | } |
720 | ||
10556cb2 | 721 | static int proc_sys_permission(struct inode *inode, int mask) |
77b14db5 EB |
722 | { |
723 | /* | |
724 | * sysctl entries that are not writeable, | |
725 | * are _NOT_ writeable, capabilities or not. | |
726 | */ | |
f696a365 MS |
727 | struct ctl_table_header *head; |
728 | struct ctl_table *table; | |
77b14db5 EB |
729 | int error; |
730 | ||
f696a365 MS |
731 | /* Executable files are not allowed under /proc/sys/ */ |
732 | if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode)) | |
733 | return -EACCES; | |
734 | ||
735 | head = grab_header(inode); | |
9043476f AV |
736 | if (IS_ERR(head)) |
737 | return PTR_ERR(head); | |
77b14db5 | 738 | |
f696a365 | 739 | table = PROC_I(inode)->sysctl_entry; |
9043476f AV |
740 | if (!table) /* global root - r-xr-xr-x */ |
741 | error = mask & MAY_WRITE ? -EACCES : 0; | |
742 | else /* Use the permissions on the sysctl table entry */ | |
73f7ef43 | 743 | error = sysctl_perm(head, table, mask & ~MAY_NOT_BLOCK); |
77b14db5 | 744 | |
77b14db5 EB |
745 | sysctl_head_finish(head); |
746 | return error; | |
747 | } | |
748 | ||
749 | static int proc_sys_setattr(struct dentry *dentry, struct iattr *attr) | |
750 | { | |
2b0143b5 | 751 | struct inode *inode = d_inode(dentry); |
77b14db5 EB |
752 | int error; |
753 | ||
754 | if (attr->ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID)) | |
755 | return -EPERM; | |
756 | ||
757 | error = inode_change_ok(inode, attr); | |
1025774c CH |
758 | if (error) |
759 | return error; | |
760 | ||
1025774c CH |
761 | setattr_copy(inode, attr); |
762 | mark_inode_dirty(inode); | |
763 | return 0; | |
77b14db5 EB |
764 | } |
765 | ||
9043476f AV |
766 | static int proc_sys_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) |
767 | { | |
2b0143b5 | 768 | struct inode *inode = d_inode(dentry); |
9043476f AV |
769 | struct ctl_table_header *head = grab_header(inode); |
770 | struct ctl_table *table = PROC_I(inode)->sysctl_entry; | |
771 | ||
772 | if (IS_ERR(head)) | |
773 | return PTR_ERR(head); | |
774 | ||
775 | generic_fillattr(inode, stat); | |
776 | if (table) | |
777 | stat->mode = (stat->mode & S_IFMT) | table->mode; | |
778 | ||
779 | sysctl_head_finish(head); | |
780 | return 0; | |
781 | } | |
782 | ||
77b14db5 | 783 | static const struct file_operations proc_sys_file_operations = { |
f1ecf068 LDM |
784 | .open = proc_sys_open, |
785 | .poll = proc_sys_poll, | |
77b14db5 EB |
786 | .read = proc_sys_read, |
787 | .write = proc_sys_write, | |
6038f373 | 788 | .llseek = default_llseek, |
9043476f AV |
789 | }; |
790 | ||
791 | static const struct file_operations proc_sys_dir_file_operations = { | |
887df078 | 792 | .read = generic_read_dir, |
f50752ea | 793 | .iterate_shared = proc_sys_readdir, |
3222a3e5 | 794 | .llseek = generic_file_llseek, |
77b14db5 EB |
795 | }; |
796 | ||
03a44825 | 797 | static const struct inode_operations proc_sys_inode_operations = { |
9043476f AV |
798 | .permission = proc_sys_permission, |
799 | .setattr = proc_sys_setattr, | |
800 | .getattr = proc_sys_getattr, | |
801 | }; | |
802 | ||
803 | static const struct inode_operations proc_sys_dir_operations = { | |
77b14db5 EB |
804 | .lookup = proc_sys_lookup, |
805 | .permission = proc_sys_permission, | |
806 | .setattr = proc_sys_setattr, | |
9043476f | 807 | .getattr = proc_sys_getattr, |
77b14db5 EB |
808 | }; |
809 | ||
0b728e19 | 810 | static int proc_sys_revalidate(struct dentry *dentry, unsigned int flags) |
77b14db5 | 811 | { |
0b728e19 | 812 | if (flags & LOOKUP_RCU) |
34286d66 | 813 | return -ECHILD; |
2b0143b5 | 814 | return !PROC_I(d_inode(dentry))->sysctl->unregistering; |
9043476f AV |
815 | } |
816 | ||
fe15ce44 | 817 | static int proc_sys_delete(const struct dentry *dentry) |
9043476f | 818 | { |
2b0143b5 | 819 | return !!PROC_I(d_inode(dentry))->sysctl->unregistering; |
9043476f AV |
820 | } |
821 | ||
1f87f0b5 EB |
822 | static int sysctl_is_seen(struct ctl_table_header *p) |
823 | { | |
824 | struct ctl_table_set *set = p->set; | |
825 | int res; | |
826 | spin_lock(&sysctl_lock); | |
827 | if (p->unregistering) | |
828 | res = 0; | |
829 | else if (!set->is_seen) | |
830 | res = 1; | |
831 | else | |
832 | res = set->is_seen(set); | |
833 | spin_unlock(&sysctl_lock); | |
834 | return res; | |
835 | } | |
836 | ||
6fa67e70 | 837 | static int proc_sys_compare(const struct dentry *dentry, |
621e155a | 838 | unsigned int len, const char *str, const struct qstr *name) |
9043476f | 839 | { |
dfef6dcd | 840 | struct ctl_table_header *head; |
da53be12 LT |
841 | struct inode *inode; |
842 | ||
31e6b01f NP |
843 | /* Although proc doesn't have negative dentries, rcu-walk means |
844 | * that inode here can be NULL */ | |
dfef6dcd | 845 | /* AV: can it, indeed? */ |
2b0143b5 | 846 | inode = d_inode_rcu(dentry); |
31e6b01f | 847 | if (!inode) |
dfef6dcd | 848 | return 1; |
621e155a | 849 | if (name->len != len) |
9043476f | 850 | return 1; |
621e155a | 851 | if (memcmp(name->name, str, len)) |
9043476f | 852 | return 1; |
dfef6dcd AV |
853 | head = rcu_dereference(PROC_I(inode)->sysctl); |
854 | return !head || !sysctl_is_seen(head); | |
77b14db5 EB |
855 | } |
856 | ||
d72f71eb | 857 | static const struct dentry_operations proc_sys_dentry_operations = { |
77b14db5 | 858 | .d_revalidate = proc_sys_revalidate, |
9043476f AV |
859 | .d_delete = proc_sys_delete, |
860 | .d_compare = proc_sys_compare, | |
77b14db5 EB |
861 | }; |
862 | ||
0e47c99d EB |
863 | static struct ctl_dir *find_subdir(struct ctl_dir *dir, |
864 | const char *name, int namelen) | |
1f87f0b5 | 865 | { |
7ec66d06 EB |
866 | struct ctl_table_header *head; |
867 | struct ctl_table *entry; | |
1f87f0b5 | 868 | |
0e47c99d | 869 | entry = find_entry(&head, dir, name, namelen); |
7ec66d06 EB |
870 | if (!entry) |
871 | return ERR_PTR(-ENOENT); | |
51f72f4a EB |
872 | if (!S_ISDIR(entry->mode)) |
873 | return ERR_PTR(-ENOTDIR); | |
874 | return container_of(head, struct ctl_dir, header); | |
7ec66d06 EB |
875 | } |
876 | ||
877 | static struct ctl_dir *new_dir(struct ctl_table_set *set, | |
0e47c99d | 878 | const char *name, int namelen) |
7ec66d06 EB |
879 | { |
880 | struct ctl_table *table; | |
881 | struct ctl_dir *new; | |
ac13ac6f | 882 | struct ctl_node *node; |
7ec66d06 | 883 | char *new_name; |
1f87f0b5 | 884 | |
ac13ac6f EB |
885 | new = kzalloc(sizeof(*new) + sizeof(struct ctl_node) + |
886 | sizeof(struct ctl_table)*2 + namelen + 1, | |
887 | GFP_KERNEL); | |
7ec66d06 | 888 | if (!new) |
1f87f0b5 EB |
889 | return NULL; |
890 | ||
ac13ac6f EB |
891 | node = (struct ctl_node *)(new + 1); |
892 | table = (struct ctl_table *)(node + 1); | |
7ec66d06 EB |
893 | new_name = (char *)(table + 2); |
894 | memcpy(new_name, name, namelen); | |
895 | new_name[namelen] = '\0'; | |
896 | table[0].procname = new_name; | |
897 | table[0].mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
ac13ac6f | 898 | init_header(&new->header, set->dir.header.root, set, node, table); |
7ec66d06 EB |
899 | |
900 | return new; | |
1f87f0b5 EB |
901 | } |
902 | ||
60f126d9 EB |
903 | /** |
904 | * get_subdir - find or create a subdir with the specified name. | |
905 | * @dir: Directory to create the subdirectory in | |
906 | * @name: The name of the subdirectory to find or create | |
907 | * @namelen: The length of name | |
908 | * | |
909 | * Takes a directory with an elevated reference count so we know that | |
910 | * if we drop the lock the directory will not go away. Upon success | |
911 | * the reference is moved from @dir to the returned subdirectory. | |
912 | * Upon error an error code is returned and the reference on @dir is | |
913 | * simply dropped. | |
914 | */ | |
0e47c99d EB |
915 | static struct ctl_dir *get_subdir(struct ctl_dir *dir, |
916 | const char *name, int namelen) | |
1f87f0b5 | 917 | { |
0e47c99d | 918 | struct ctl_table_set *set = dir->header.set; |
7ec66d06 | 919 | struct ctl_dir *subdir, *new = NULL; |
0eb97f38 | 920 | int err; |
1f87f0b5 | 921 | |
7ec66d06 | 922 | spin_lock(&sysctl_lock); |
0e47c99d | 923 | subdir = find_subdir(dir, name, namelen); |
7ec66d06 EB |
924 | if (!IS_ERR(subdir)) |
925 | goto found; | |
926 | if (PTR_ERR(subdir) != -ENOENT) | |
927 | goto failed; | |
928 | ||
929 | spin_unlock(&sysctl_lock); | |
930 | new = new_dir(set, name, namelen); | |
931 | spin_lock(&sysctl_lock); | |
932 | subdir = ERR_PTR(-ENOMEM); | |
933 | if (!new) | |
934 | goto failed; | |
935 | ||
60f126d9 | 936 | /* Was the subdir added while we dropped the lock? */ |
0e47c99d | 937 | subdir = find_subdir(dir, name, namelen); |
7ec66d06 EB |
938 | if (!IS_ERR(subdir)) |
939 | goto found; | |
940 | if (PTR_ERR(subdir) != -ENOENT) | |
941 | goto failed; | |
942 | ||
60f126d9 | 943 | /* Nope. Use the our freshly made directory entry. */ |
0eb97f38 EB |
944 | err = insert_header(dir, &new->header); |
945 | subdir = ERR_PTR(err); | |
946 | if (err) | |
0e47c99d | 947 | goto failed; |
7ec66d06 EB |
948 | subdir = new; |
949 | found: | |
950 | subdir->header.nreg++; | |
951 | failed: | |
a1c83681 | 952 | if (IS_ERR(subdir)) { |
87ebdc00 | 953 | pr_err("sysctl could not get directory: "); |
6980128f | 954 | sysctl_print_dir(dir); |
87ebdc00 | 955 | pr_cont("/%*.*s %ld\n", |
7ec66d06 | 956 | namelen, namelen, name, PTR_ERR(subdir)); |
1f87f0b5 | 957 | } |
7ec66d06 EB |
958 | drop_sysctl_table(&dir->header); |
959 | if (new) | |
960 | drop_sysctl_table(&new->header); | |
961 | spin_unlock(&sysctl_lock); | |
962 | return subdir; | |
1f87f0b5 EB |
963 | } |
964 | ||
0e47c99d EB |
965 | static struct ctl_dir *xlate_dir(struct ctl_table_set *set, struct ctl_dir *dir) |
966 | { | |
967 | struct ctl_dir *parent; | |
968 | const char *procname; | |
969 | if (!dir->header.parent) | |
970 | return &set->dir; | |
971 | parent = xlate_dir(set, dir->header.parent); | |
972 | if (IS_ERR(parent)) | |
973 | return parent; | |
974 | procname = dir->header.ctl_table[0].procname; | |
975 | return find_subdir(parent, procname, strlen(procname)); | |
976 | } | |
977 | ||
978 | static int sysctl_follow_link(struct ctl_table_header **phead, | |
979 | struct ctl_table **pentry, struct nsproxy *namespaces) | |
980 | { | |
981 | struct ctl_table_header *head; | |
982 | struct ctl_table_root *root; | |
983 | struct ctl_table_set *set; | |
984 | struct ctl_table *entry; | |
985 | struct ctl_dir *dir; | |
986 | int ret; | |
987 | ||
0e47c99d EB |
988 | ret = 0; |
989 | spin_lock(&sysctl_lock); | |
990 | root = (*pentry)->data; | |
991 | set = lookup_header_set(root, namespaces); | |
992 | dir = xlate_dir(set, (*phead)->parent); | |
993 | if (IS_ERR(dir)) | |
994 | ret = PTR_ERR(dir); | |
995 | else { | |
996 | const char *procname = (*pentry)->procname; | |
997 | head = NULL; | |
998 | entry = find_entry(&head, dir, procname, strlen(procname)); | |
999 | ret = -ENOENT; | |
1000 | if (entry && use_table(head)) { | |
1001 | unuse_table(*phead); | |
1002 | *phead = head; | |
1003 | *pentry = entry; | |
1004 | ret = 0; | |
1005 | } | |
1006 | } | |
1007 | ||
1008 | spin_unlock(&sysctl_lock); | |
1009 | return ret; | |
1010 | } | |
1011 | ||
7c60c48f | 1012 | static int sysctl_err(const char *path, struct ctl_table *table, char *fmt, ...) |
1f87f0b5 | 1013 | { |
7c60c48f EB |
1014 | struct va_format vaf; |
1015 | va_list args; | |
1f87f0b5 | 1016 | |
7c60c48f EB |
1017 | va_start(args, fmt); |
1018 | vaf.fmt = fmt; | |
1019 | vaf.va = &args; | |
1020 | ||
87ebdc00 AM |
1021 | pr_err("sysctl table check failed: %s/%s %pV\n", |
1022 | path, table->procname, &vaf); | |
1f87f0b5 | 1023 | |
7c60c48f EB |
1024 | va_end(args); |
1025 | return -EINVAL; | |
1f87f0b5 EB |
1026 | } |
1027 | ||
7c60c48f | 1028 | static int sysctl_check_table(const char *path, struct ctl_table *table) |
1f87f0b5 | 1029 | { |
7c60c48f | 1030 | int err = 0; |
1f87f0b5 | 1031 | for (; table->procname; table++) { |
1f87f0b5 | 1032 | if (table->child) |
7c60c48f EB |
1033 | err = sysctl_err(path, table, "Not a file"); |
1034 | ||
1035 | if ((table->proc_handler == proc_dostring) || | |
1036 | (table->proc_handler == proc_dointvec) || | |
1037 | (table->proc_handler == proc_dointvec_minmax) || | |
1038 | (table->proc_handler == proc_dointvec_jiffies) || | |
1039 | (table->proc_handler == proc_dointvec_userhz_jiffies) || | |
1040 | (table->proc_handler == proc_dointvec_ms_jiffies) || | |
1041 | (table->proc_handler == proc_doulongvec_minmax) || | |
1042 | (table->proc_handler == proc_doulongvec_ms_jiffies_minmax)) { | |
1043 | if (!table->data) | |
1044 | err = sysctl_err(path, table, "No data"); | |
1045 | if (!table->maxlen) | |
1046 | err = sysctl_err(path, table, "No maxlen"); | |
1047 | } | |
1048 | if (!table->proc_handler) | |
1049 | err = sysctl_err(path, table, "No proc_handler"); | |
1050 | ||
1051 | if ((table->mode & (S_IRUGO|S_IWUGO)) != table->mode) | |
1052 | err = sysctl_err(path, table, "bogus .mode 0%o", | |
1053 | table->mode); | |
1f87f0b5 | 1054 | } |
7c60c48f | 1055 | return err; |
1f87f0b5 | 1056 | } |
1f87f0b5 | 1057 | |
0e47c99d EB |
1058 | static struct ctl_table_header *new_links(struct ctl_dir *dir, struct ctl_table *table, |
1059 | struct ctl_table_root *link_root) | |
1060 | { | |
1061 | struct ctl_table *link_table, *entry, *link; | |
1062 | struct ctl_table_header *links; | |
ac13ac6f | 1063 | struct ctl_node *node; |
0e47c99d EB |
1064 | char *link_name; |
1065 | int nr_entries, name_bytes; | |
1066 | ||
1067 | name_bytes = 0; | |
1068 | nr_entries = 0; | |
1069 | for (entry = table; entry->procname; entry++) { | |
1070 | nr_entries++; | |
1071 | name_bytes += strlen(entry->procname) + 1; | |
1072 | } | |
1073 | ||
1074 | links = kzalloc(sizeof(struct ctl_table_header) + | |
ac13ac6f | 1075 | sizeof(struct ctl_node)*nr_entries + |
0e47c99d EB |
1076 | sizeof(struct ctl_table)*(nr_entries + 1) + |
1077 | name_bytes, | |
1078 | GFP_KERNEL); | |
1079 | ||
1080 | if (!links) | |
1081 | return NULL; | |
1082 | ||
ac13ac6f EB |
1083 | node = (struct ctl_node *)(links + 1); |
1084 | link_table = (struct ctl_table *)(node + nr_entries); | |
0e47c99d EB |
1085 | link_name = (char *)&link_table[nr_entries + 1]; |
1086 | ||
1087 | for (link = link_table, entry = table; entry->procname; link++, entry++) { | |
1088 | int len = strlen(entry->procname) + 1; | |
1089 | memcpy(link_name, entry->procname, len); | |
1090 | link->procname = link_name; | |
1091 | link->mode = S_IFLNK|S_IRWXUGO; | |
1092 | link->data = link_root; | |
1093 | link_name += len; | |
1094 | } | |
ac13ac6f | 1095 | init_header(links, dir->header.root, dir->header.set, node, link_table); |
0e47c99d EB |
1096 | links->nreg = nr_entries; |
1097 | ||
1098 | return links; | |
1099 | } | |
1100 | ||
1101 | static bool get_links(struct ctl_dir *dir, | |
1102 | struct ctl_table *table, struct ctl_table_root *link_root) | |
1103 | { | |
1104 | struct ctl_table_header *head; | |
1105 | struct ctl_table *entry, *link; | |
1106 | ||
1107 | /* Are there links available for every entry in table? */ | |
1108 | for (entry = table; entry->procname; entry++) { | |
1109 | const char *procname = entry->procname; | |
1110 | link = find_entry(&head, dir, procname, strlen(procname)); | |
1111 | if (!link) | |
1112 | return false; | |
1113 | if (S_ISDIR(link->mode) && S_ISDIR(entry->mode)) | |
1114 | continue; | |
1115 | if (S_ISLNK(link->mode) && (link->data == link_root)) | |
1116 | continue; | |
1117 | return false; | |
1118 | } | |
1119 | ||
1120 | /* The checks passed. Increase the registration count on the links */ | |
1121 | for (entry = table; entry->procname; entry++) { | |
1122 | const char *procname = entry->procname; | |
1123 | link = find_entry(&head, dir, procname, strlen(procname)); | |
1124 | head->nreg++; | |
1125 | } | |
1126 | return true; | |
1127 | } | |
1128 | ||
1129 | static int insert_links(struct ctl_table_header *head) | |
1130 | { | |
1131 | struct ctl_table_set *root_set = &sysctl_table_root.default_set; | |
1132 | struct ctl_dir *core_parent = NULL; | |
1133 | struct ctl_table_header *links; | |
1134 | int err; | |
1135 | ||
1136 | if (head->set == root_set) | |
1137 | return 0; | |
1138 | ||
1139 | core_parent = xlate_dir(root_set, head->parent); | |
1140 | if (IS_ERR(core_parent)) | |
1141 | return 0; | |
1142 | ||
1143 | if (get_links(core_parent, head->ctl_table, head->root)) | |
1144 | return 0; | |
1145 | ||
1146 | core_parent->header.nreg++; | |
1147 | spin_unlock(&sysctl_lock); | |
1148 | ||
1149 | links = new_links(core_parent, head->ctl_table, head->root); | |
1150 | ||
1151 | spin_lock(&sysctl_lock); | |
1152 | err = -ENOMEM; | |
1153 | if (!links) | |
1154 | goto out; | |
1155 | ||
1156 | err = 0; | |
1157 | if (get_links(core_parent, head->ctl_table, head->root)) { | |
1158 | kfree(links); | |
1159 | goto out; | |
1160 | } | |
1161 | ||
1162 | err = insert_header(core_parent, links); | |
1163 | if (err) | |
1164 | kfree(links); | |
1165 | out: | |
1166 | drop_sysctl_table(&core_parent->header); | |
1167 | return err; | |
1168 | } | |
1169 | ||
1f87f0b5 | 1170 | /** |
f728019b | 1171 | * __register_sysctl_table - register a leaf sysctl table |
60a47a2e | 1172 | * @set: Sysctl tree to register on |
1f87f0b5 EB |
1173 | * @path: The path to the directory the sysctl table is in. |
1174 | * @table: the top-level table structure | |
1175 | * | |
1176 | * Register a sysctl table hierarchy. @table should be a filled in ctl_table | |
1177 | * array. A completely 0 filled entry terminates the table. | |
1178 | * | |
1179 | * The members of the &struct ctl_table structure are used as follows: | |
1180 | * | |
1181 | * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not | |
1182 | * enter a sysctl file | |
1183 | * | |
1184 | * data - a pointer to data for use by proc_handler | |
1185 | * | |
1186 | * maxlen - the maximum size in bytes of the data | |
1187 | * | |
f728019b | 1188 | * mode - the file permissions for the /proc/sys file |
1f87f0b5 | 1189 | * |
f728019b | 1190 | * child - must be %NULL. |
1f87f0b5 EB |
1191 | * |
1192 | * proc_handler - the text handler routine (described below) | |
1193 | * | |
1f87f0b5 EB |
1194 | * extra1, extra2 - extra pointers usable by the proc handler routines |
1195 | * | |
1196 | * Leaf nodes in the sysctl tree will be represented by a single file | |
1197 | * under /proc; non-leaf nodes will be represented by directories. | |
1198 | * | |
f728019b EB |
1199 | * There must be a proc_handler routine for any terminal nodes. |
1200 | * Several default handlers are available to cover common cases - | |
1f87f0b5 EB |
1201 | * |
1202 | * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), | |
1203 | * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), | |
1204 | * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() | |
1205 | * | |
1206 | * It is the handler's job to read the input buffer from user memory | |
1207 | * and process it. The handler should return 0 on success. | |
1208 | * | |
1209 | * This routine returns %NULL on a failure to register, and a pointer | |
1210 | * to the table header on success. | |
1211 | */ | |
6e9d5164 | 1212 | struct ctl_table_header *__register_sysctl_table( |
60a47a2e | 1213 | struct ctl_table_set *set, |
6e9d5164 | 1214 | const char *path, struct ctl_table *table) |
1f87f0b5 | 1215 | { |
60a47a2e | 1216 | struct ctl_table_root *root = set->dir.header.root; |
1f87f0b5 | 1217 | struct ctl_table_header *header; |
6e9d5164 | 1218 | const char *name, *nextname; |
7ec66d06 | 1219 | struct ctl_dir *dir; |
ac13ac6f EB |
1220 | struct ctl_table *entry; |
1221 | struct ctl_node *node; | |
1222 | int nr_entries = 0; | |
1223 | ||
1224 | for (entry = table; entry->procname; entry++) | |
1225 | nr_entries++; | |
1f87f0b5 | 1226 | |
ac13ac6f EB |
1227 | header = kzalloc(sizeof(struct ctl_table_header) + |
1228 | sizeof(struct ctl_node)*nr_entries, GFP_KERNEL); | |
1f87f0b5 EB |
1229 | if (!header) |
1230 | return NULL; | |
1231 | ||
ac13ac6f EB |
1232 | node = (struct ctl_node *)(header + 1); |
1233 | init_header(header, root, set, node, table); | |
7ec66d06 EB |
1234 | if (sysctl_check_table(path, table)) |
1235 | goto fail; | |
1236 | ||
1237 | spin_lock(&sysctl_lock); | |
0e47c99d | 1238 | dir = &set->dir; |
60f126d9 | 1239 | /* Reference moved down the diretory tree get_subdir */ |
7ec66d06 EB |
1240 | dir->header.nreg++; |
1241 | spin_unlock(&sysctl_lock); | |
1f87f0b5 | 1242 | |
7ec66d06 | 1243 | /* Find the directory for the ctl_table */ |
6e9d5164 EB |
1244 | for (name = path; name; name = nextname) { |
1245 | int namelen; | |
1246 | nextname = strchr(name, '/'); | |
1247 | if (nextname) { | |
1248 | namelen = nextname - name; | |
1249 | nextname++; | |
1250 | } else { | |
1251 | namelen = strlen(name); | |
1252 | } | |
1253 | if (namelen == 0) | |
1254 | continue; | |
1f87f0b5 | 1255 | |
0e47c99d | 1256 | dir = get_subdir(dir, name, namelen); |
7ec66d06 EB |
1257 | if (IS_ERR(dir)) |
1258 | goto fail; | |
1f87f0b5 | 1259 | } |
0e47c99d | 1260 | |
1f87f0b5 | 1261 | spin_lock(&sysctl_lock); |
0e47c99d | 1262 | if (insert_header(dir, header)) |
7ec66d06 | 1263 | goto fail_put_dir_locked; |
0e47c99d | 1264 | |
7ec66d06 | 1265 | drop_sysctl_table(&dir->header); |
1f87f0b5 EB |
1266 | spin_unlock(&sysctl_lock); |
1267 | ||
1268 | return header; | |
0e47c99d | 1269 | |
7ec66d06 EB |
1270 | fail_put_dir_locked: |
1271 | drop_sysctl_table(&dir->header); | |
7c60c48f EB |
1272 | spin_unlock(&sysctl_lock); |
1273 | fail: | |
1274 | kfree(header); | |
1275 | dump_stack(); | |
1276 | return NULL; | |
1f87f0b5 EB |
1277 | } |
1278 | ||
fea478d4 EB |
1279 | /** |
1280 | * register_sysctl - register a sysctl table | |
1281 | * @path: The path to the directory the sysctl table is in. | |
1282 | * @table: the table structure | |
1283 | * | |
1284 | * Register a sysctl table. @table should be a filled in ctl_table | |
1285 | * array. A completely 0 filled entry terminates the table. | |
1286 | * | |
1287 | * See __register_sysctl_table for more details. | |
1288 | */ | |
1289 | struct ctl_table_header *register_sysctl(const char *path, struct ctl_table *table) | |
1290 | { | |
1291 | return __register_sysctl_table(&sysctl_table_root.default_set, | |
1292 | path, table); | |
1293 | } | |
1294 | EXPORT_SYMBOL(register_sysctl); | |
1295 | ||
6e9d5164 EB |
1296 | static char *append_path(const char *path, char *pos, const char *name) |
1297 | { | |
1298 | int namelen; | |
1299 | namelen = strlen(name); | |
1300 | if (((pos - path) + namelen + 2) >= PATH_MAX) | |
1301 | return NULL; | |
1302 | memcpy(pos, name, namelen); | |
1303 | pos[namelen] = '/'; | |
1304 | pos[namelen + 1] = '\0'; | |
1305 | pos += namelen + 1; | |
1306 | return pos; | |
1307 | } | |
1308 | ||
f728019b EB |
1309 | static int count_subheaders(struct ctl_table *table) |
1310 | { | |
1311 | int has_files = 0; | |
1312 | int nr_subheaders = 0; | |
1313 | struct ctl_table *entry; | |
1314 | ||
1315 | /* special case: no directory and empty directory */ | |
1316 | if (!table || !table->procname) | |
1317 | return 1; | |
1318 | ||
1319 | for (entry = table; entry->procname; entry++) { | |
1320 | if (entry->child) | |
1321 | nr_subheaders += count_subheaders(entry->child); | |
1322 | else | |
1323 | has_files = 1; | |
1324 | } | |
1325 | return nr_subheaders + has_files; | |
1326 | } | |
1327 | ||
1328 | static int register_leaf_sysctl_tables(const char *path, char *pos, | |
60a47a2e | 1329 | struct ctl_table_header ***subheader, struct ctl_table_set *set, |
f728019b EB |
1330 | struct ctl_table *table) |
1331 | { | |
1332 | struct ctl_table *ctl_table_arg = NULL; | |
1333 | struct ctl_table *entry, *files; | |
1334 | int nr_files = 0; | |
1335 | int nr_dirs = 0; | |
1336 | int err = -ENOMEM; | |
1337 | ||
1338 | for (entry = table; entry->procname; entry++) { | |
1339 | if (entry->child) | |
1340 | nr_dirs++; | |
1341 | else | |
1342 | nr_files++; | |
1343 | } | |
1344 | ||
1345 | files = table; | |
1346 | /* If there are mixed files and directories we need a new table */ | |
1347 | if (nr_dirs && nr_files) { | |
1348 | struct ctl_table *new; | |
1349 | files = kzalloc(sizeof(struct ctl_table) * (nr_files + 1), | |
1350 | GFP_KERNEL); | |
1351 | if (!files) | |
1352 | goto out; | |
1353 | ||
1354 | ctl_table_arg = files; | |
1355 | for (new = files, entry = table; entry->procname; entry++) { | |
1356 | if (entry->child) | |
1357 | continue; | |
1358 | *new = *entry; | |
1359 | new++; | |
1360 | } | |
1361 | } | |
1362 | ||
1363 | /* Register everything except a directory full of subdirectories */ | |
1364 | if (nr_files || !nr_dirs) { | |
1365 | struct ctl_table_header *header; | |
60a47a2e | 1366 | header = __register_sysctl_table(set, path, files); |
f728019b EB |
1367 | if (!header) { |
1368 | kfree(ctl_table_arg); | |
1369 | goto out; | |
1370 | } | |
1371 | ||
1372 | /* Remember if we need to free the file table */ | |
1373 | header->ctl_table_arg = ctl_table_arg; | |
1374 | **subheader = header; | |
1375 | (*subheader)++; | |
1376 | } | |
1377 | ||
1378 | /* Recurse into the subdirectories. */ | |
1379 | for (entry = table; entry->procname; entry++) { | |
1380 | char *child_pos; | |
1381 | ||
1382 | if (!entry->child) | |
1383 | continue; | |
1384 | ||
1385 | err = -ENAMETOOLONG; | |
1386 | child_pos = append_path(path, pos, entry->procname); | |
1387 | if (!child_pos) | |
1388 | goto out; | |
1389 | ||
1390 | err = register_leaf_sysctl_tables(path, child_pos, subheader, | |
60a47a2e | 1391 | set, entry->child); |
f728019b EB |
1392 | pos[0] = '\0'; |
1393 | if (err) | |
1394 | goto out; | |
1395 | } | |
1396 | err = 0; | |
1397 | out: | |
1398 | /* On failure our caller will unregister all registered subheaders */ | |
1399 | return err; | |
1400 | } | |
1401 | ||
6e9d5164 EB |
1402 | /** |
1403 | * __register_sysctl_paths - register a sysctl table hierarchy | |
60a47a2e | 1404 | * @set: Sysctl tree to register on |
6e9d5164 EB |
1405 | * @path: The path to the directory the sysctl table is in. |
1406 | * @table: the top-level table structure | |
1407 | * | |
1408 | * Register a sysctl table hierarchy. @table should be a filled in ctl_table | |
1409 | * array. A completely 0 filled entry terminates the table. | |
1410 | * | |
1411 | * See __register_sysctl_table for more details. | |
1412 | */ | |
1413 | struct ctl_table_header *__register_sysctl_paths( | |
60a47a2e | 1414 | struct ctl_table_set *set, |
6e9d5164 EB |
1415 | const struct ctl_path *path, struct ctl_table *table) |
1416 | { | |
ec6a5266 | 1417 | struct ctl_table *ctl_table_arg = table; |
f728019b EB |
1418 | int nr_subheaders = count_subheaders(table); |
1419 | struct ctl_table_header *header = NULL, **subheaders, **subheader; | |
6e9d5164 EB |
1420 | const struct ctl_path *component; |
1421 | char *new_path, *pos; | |
1422 | ||
1423 | pos = new_path = kmalloc(PATH_MAX, GFP_KERNEL); | |
1424 | if (!new_path) | |
1425 | return NULL; | |
1426 | ||
1427 | pos[0] = '\0'; | |
1428 | for (component = path; component->procname; component++) { | |
1429 | pos = append_path(new_path, pos, component->procname); | |
1430 | if (!pos) | |
1431 | goto out; | |
1432 | } | |
ec6a5266 EB |
1433 | while (table->procname && table->child && !table[1].procname) { |
1434 | pos = append_path(new_path, pos, table->procname); | |
1435 | if (!pos) | |
1436 | goto out; | |
1437 | table = table->child; | |
1438 | } | |
f728019b | 1439 | if (nr_subheaders == 1) { |
60a47a2e | 1440 | header = __register_sysctl_table(set, new_path, table); |
f728019b EB |
1441 | if (header) |
1442 | header->ctl_table_arg = ctl_table_arg; | |
1443 | } else { | |
1444 | header = kzalloc(sizeof(*header) + | |
1445 | sizeof(*subheaders)*nr_subheaders, GFP_KERNEL); | |
1446 | if (!header) | |
1447 | goto out; | |
1448 | ||
1449 | subheaders = (struct ctl_table_header **) (header + 1); | |
1450 | subheader = subheaders; | |
ec6a5266 | 1451 | header->ctl_table_arg = ctl_table_arg; |
f728019b EB |
1452 | |
1453 | if (register_leaf_sysctl_tables(new_path, pos, &subheader, | |
60a47a2e | 1454 | set, table)) |
f728019b EB |
1455 | goto err_register_leaves; |
1456 | } | |
1457 | ||
6e9d5164 EB |
1458 | out: |
1459 | kfree(new_path); | |
1460 | return header; | |
f728019b EB |
1461 | |
1462 | err_register_leaves: | |
1463 | while (subheader > subheaders) { | |
1464 | struct ctl_table_header *subh = *(--subheader); | |
1465 | struct ctl_table *table = subh->ctl_table_arg; | |
1466 | unregister_sysctl_table(subh); | |
1467 | kfree(table); | |
1468 | } | |
1469 | kfree(header); | |
1470 | header = NULL; | |
1471 | goto out; | |
6e9d5164 EB |
1472 | } |
1473 | ||
1f87f0b5 EB |
1474 | /** |
1475 | * register_sysctl_table_path - register a sysctl table hierarchy | |
1476 | * @path: The path to the directory the sysctl table is in. | |
1477 | * @table: the top-level table structure | |
1478 | * | |
1479 | * Register a sysctl table hierarchy. @table should be a filled in ctl_table | |
1480 | * array. A completely 0 filled entry terminates the table. | |
1481 | * | |
1482 | * See __register_sysctl_paths for more details. | |
1483 | */ | |
1484 | struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path, | |
1485 | struct ctl_table *table) | |
1486 | { | |
60a47a2e | 1487 | return __register_sysctl_paths(&sysctl_table_root.default_set, |
1f87f0b5 EB |
1488 | path, table); |
1489 | } | |
1490 | EXPORT_SYMBOL(register_sysctl_paths); | |
1491 | ||
1492 | /** | |
1493 | * register_sysctl_table - register a sysctl table hierarchy | |
1494 | * @table: the top-level table structure | |
1495 | * | |
1496 | * Register a sysctl table hierarchy. @table should be a filled in ctl_table | |
1497 | * array. A completely 0 filled entry terminates the table. | |
1498 | * | |
1499 | * See register_sysctl_paths for more details. | |
1500 | */ | |
1501 | struct ctl_table_header *register_sysctl_table(struct ctl_table *table) | |
1502 | { | |
1503 | static const struct ctl_path null_path[] = { {} }; | |
1504 | ||
1505 | return register_sysctl_paths(null_path, table); | |
1506 | } | |
1507 | EXPORT_SYMBOL(register_sysctl_table); | |
1508 | ||
0e47c99d EB |
1509 | static void put_links(struct ctl_table_header *header) |
1510 | { | |
1511 | struct ctl_table_set *root_set = &sysctl_table_root.default_set; | |
1512 | struct ctl_table_root *root = header->root; | |
1513 | struct ctl_dir *parent = header->parent; | |
1514 | struct ctl_dir *core_parent; | |
1515 | struct ctl_table *entry; | |
1516 | ||
1517 | if (header->set == root_set) | |
1518 | return; | |
1519 | ||
1520 | core_parent = xlate_dir(root_set, parent); | |
1521 | if (IS_ERR(core_parent)) | |
1522 | return; | |
1523 | ||
1524 | for (entry = header->ctl_table; entry->procname; entry++) { | |
1525 | struct ctl_table_header *link_head; | |
1526 | struct ctl_table *link; | |
1527 | const char *name = entry->procname; | |
1528 | ||
1529 | link = find_entry(&link_head, core_parent, name, strlen(name)); | |
1530 | if (link && | |
1531 | ((S_ISDIR(link->mode) && S_ISDIR(entry->mode)) || | |
1532 | (S_ISLNK(link->mode) && (link->data == root)))) { | |
1533 | drop_sysctl_table(link_head); | |
1534 | } | |
1535 | else { | |
87ebdc00 | 1536 | pr_err("sysctl link missing during unregister: "); |
0e47c99d | 1537 | sysctl_print_dir(parent); |
87ebdc00 | 1538 | pr_cont("/%s\n", name); |
0e47c99d EB |
1539 | } |
1540 | } | |
1541 | } | |
1542 | ||
938aaa4f EB |
1543 | static void drop_sysctl_table(struct ctl_table_header *header) |
1544 | { | |
7ec66d06 EB |
1545 | struct ctl_dir *parent = header->parent; |
1546 | ||
938aaa4f EB |
1547 | if (--header->nreg) |
1548 | return; | |
1549 | ||
0e47c99d | 1550 | put_links(header); |
938aaa4f | 1551 | start_unregistering(header); |
938aaa4f EB |
1552 | if (!--header->count) |
1553 | kfree_rcu(header, rcu); | |
7ec66d06 EB |
1554 | |
1555 | if (parent) | |
1556 | drop_sysctl_table(&parent->header); | |
938aaa4f EB |
1557 | } |
1558 | ||
1f87f0b5 EB |
1559 | /** |
1560 | * unregister_sysctl_table - unregister a sysctl table hierarchy | |
1561 | * @header: the header returned from register_sysctl_table | |
1562 | * | |
1563 | * Unregisters the sysctl table and all children. proc entries may not | |
1564 | * actually be removed until they are no longer used by anyone. | |
1565 | */ | |
1566 | void unregister_sysctl_table(struct ctl_table_header * header) | |
1567 | { | |
f728019b | 1568 | int nr_subheaders; |
1f87f0b5 EB |
1569 | might_sleep(); |
1570 | ||
1571 | if (header == NULL) | |
1572 | return; | |
1573 | ||
f728019b EB |
1574 | nr_subheaders = count_subheaders(header->ctl_table_arg); |
1575 | if (unlikely(nr_subheaders > 1)) { | |
1576 | struct ctl_table_header **subheaders; | |
1577 | int i; | |
1578 | ||
1579 | subheaders = (struct ctl_table_header **)(header + 1); | |
1580 | for (i = nr_subheaders -1; i >= 0; i--) { | |
1581 | struct ctl_table_header *subh = subheaders[i]; | |
1582 | struct ctl_table *table = subh->ctl_table_arg; | |
1583 | unregister_sysctl_table(subh); | |
1584 | kfree(table); | |
1585 | } | |
1586 | kfree(header); | |
1587 | return; | |
1588 | } | |
1589 | ||
1f87f0b5 | 1590 | spin_lock(&sysctl_lock); |
938aaa4f | 1591 | drop_sysctl_table(header); |
1f87f0b5 EB |
1592 | spin_unlock(&sysctl_lock); |
1593 | } | |
1594 | EXPORT_SYMBOL(unregister_sysctl_table); | |
1595 | ||
0e47c99d | 1596 | void setup_sysctl_set(struct ctl_table_set *set, |
9eb47c26 | 1597 | struct ctl_table_root *root, |
1f87f0b5 EB |
1598 | int (*is_seen)(struct ctl_table_set *)) |
1599 | { | |
1347440d | 1600 | memset(set, 0, sizeof(*set)); |
0e47c99d | 1601 | set->is_seen = is_seen; |
ac13ac6f | 1602 | init_header(&set->dir.header, root, set, NULL, root_table); |
1f87f0b5 EB |
1603 | } |
1604 | ||
97324cd8 EB |
1605 | void retire_sysctl_set(struct ctl_table_set *set) |
1606 | { | |
ac13ac6f | 1607 | WARN_ON(!RB_EMPTY_ROOT(&set->dir.root)); |
97324cd8 | 1608 | } |
1f87f0b5 | 1609 | |
1e0edd3f | 1610 | int __init proc_sys_init(void) |
77b14db5 | 1611 | { |
e1675231 AD |
1612 | struct proc_dir_entry *proc_sys_root; |
1613 | ||
77b14db5 | 1614 | proc_sys_root = proc_mkdir("sys", NULL); |
9043476f AV |
1615 | proc_sys_root->proc_iops = &proc_sys_dir_operations; |
1616 | proc_sys_root->proc_fops = &proc_sys_dir_file_operations; | |
77b14db5 | 1617 | proc_sys_root->nlink = 0; |
de4e83bd EB |
1618 | |
1619 | return sysctl_init(); | |
77b14db5 | 1620 | } |