Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * proc/fs/generic.c --- generic routines for the proc-fs | |
4 | * | |
5 | * This file contains generic proc-fs routines for handling | |
6 | * directories and files. | |
7 | * | |
8 | * Copyright (C) 1991, 1992 Linus Torvalds. | |
9 | * Copyright (C) 1997 Theodore Ts'o | |
10 | */ | |
11 | ||
b4884f23 | 12 | #include <linux/cache.h> |
1da177e4 LT |
13 | #include <linux/errno.h> |
14 | #include <linux/time.h> | |
15 | #include <linux/proc_fs.h> | |
16 | #include <linux/stat.h> | |
1025774c | 17 | #include <linux/mm.h> |
1da177e4 | 18 | #include <linux/module.h> |
1da4d377 | 19 | #include <linux/namei.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
87ebdc00 | 21 | #include <linux/printk.h> |
1da177e4 | 22 | #include <linux/mount.h> |
1da177e4 LT |
23 | #include <linux/init.h> |
24 | #include <linux/idr.h> | |
1da177e4 | 25 | #include <linux/bitops.h> |
64a07bd8 | 26 | #include <linux/spinlock.h> |
786d7e16 | 27 | #include <linux/completion.h> |
7c0f6ba6 | 28 | #include <linux/uaccess.h> |
fddda2b7 | 29 | #include <linux/seq_file.h> |
1da177e4 | 30 | |
fee781e6 AB |
31 | #include "internal.h" |
32 | ||
ecf1a3df | 33 | static DEFINE_RWLOCK(proc_subdir_lock); |
64a07bd8 | 34 | |
b4884f23 AD |
35 | struct kmem_cache *proc_dir_entry_cache __ro_after_init; |
36 | ||
37 | void pde_free(struct proc_dir_entry *pde) | |
38 | { | |
39 | if (S_ISLNK(pde->mode)) | |
40 | kfree(pde->data); | |
41 | if (pde->name != pde->inline_name) | |
42 | kfree(pde->name); | |
43 | kmem_cache_free(proc_dir_entry_cache, pde); | |
44 | } | |
45 | ||
93ad5bc6 | 46 | static int proc_match(const char *name, struct proc_dir_entry *de, unsigned int len) |
1da177e4 | 47 | { |
710585d4 ND |
48 | if (len < de->namelen) |
49 | return -1; | |
50 | if (len > de->namelen) | |
51 | return 1; | |
52 | ||
53 | return memcmp(name, de->name, len); | |
54 | } | |
55 | ||
56 | static struct proc_dir_entry *pde_subdir_first(struct proc_dir_entry *dir) | |
57 | { | |
4f113437 AD |
58 | return rb_entry_safe(rb_first(&dir->subdir), struct proc_dir_entry, |
59 | subdir_node); | |
710585d4 ND |
60 | } |
61 | ||
62 | static struct proc_dir_entry *pde_subdir_next(struct proc_dir_entry *dir) | |
63 | { | |
2fc1e948 ND |
64 | return rb_entry_safe(rb_next(&dir->subdir_node), struct proc_dir_entry, |
65 | subdir_node); | |
710585d4 ND |
66 | } |
67 | ||
68 | static struct proc_dir_entry *pde_subdir_find(struct proc_dir_entry *dir, | |
69 | const char *name, | |
70 | unsigned int len) | |
71 | { | |
4f113437 | 72 | struct rb_node *node = dir->subdir.rb_node; |
710585d4 ND |
73 | |
74 | while (node) { | |
4e4a7fb7 GT |
75 | struct proc_dir_entry *de = rb_entry(node, |
76 | struct proc_dir_entry, | |
77 | subdir_node); | |
93ad5bc6 | 78 | int result = proc_match(name, de, len); |
710585d4 ND |
79 | |
80 | if (result < 0) | |
81 | node = node->rb_left; | |
82 | else if (result > 0) | |
83 | node = node->rb_right; | |
84 | else | |
85 | return de; | |
86 | } | |
87 | return NULL; | |
88 | } | |
89 | ||
90 | static bool pde_subdir_insert(struct proc_dir_entry *dir, | |
91 | struct proc_dir_entry *de) | |
92 | { | |
4f113437 AD |
93 | struct rb_root *root = &dir->subdir; |
94 | struct rb_node **new = &root->rb_node, *parent = NULL; | |
710585d4 ND |
95 | |
96 | /* Figure out where to put new node */ | |
97 | while (*new) { | |
4e4a7fb7 GT |
98 | struct proc_dir_entry *this = rb_entry(*new, |
99 | struct proc_dir_entry, | |
100 | subdir_node); | |
93ad5bc6 | 101 | int result = proc_match(de->name, this, de->namelen); |
710585d4 ND |
102 | |
103 | parent = *new; | |
104 | if (result < 0) | |
105 | new = &(*new)->rb_left; | |
4f113437 | 106 | else if (result > 0) |
710585d4 | 107 | new = &(*new)->rb_right; |
4f113437 | 108 | else |
710585d4 ND |
109 | return false; |
110 | } | |
111 | ||
112 | /* Add new node and rebalance tree. */ | |
113 | rb_link_node(&de->subdir_node, parent, new); | |
4f113437 | 114 | rb_insert_color(&de->subdir_node, root); |
710585d4 | 115 | return true; |
1da177e4 LT |
116 | } |
117 | ||
c1632a0f | 118 | static int proc_notify_change(struct mnt_idmap *idmap, |
549c7297 | 119 | struct dentry *dentry, struct iattr *iattr) |
1da177e4 | 120 | { |
2b0143b5 | 121 | struct inode *inode = d_inode(dentry); |
1da177e4 LT |
122 | struct proc_dir_entry *de = PDE(inode); |
123 | int error; | |
124 | ||
c1632a0f | 125 | error = setattr_prepare(&nop_mnt_idmap, dentry, iattr); |
1da177e4 | 126 | if (error) |
1025774c | 127 | return error; |
1da177e4 | 128 | |
c1632a0f | 129 | setattr_copy(&nop_mnt_idmap, inode, iattr); |
46f69557 | 130 | |
cdf7e8dd | 131 | proc_set_user(de, inode->i_uid, inode->i_gid); |
1da177e4 | 132 | de->mode = inode->i_mode; |
1025774c | 133 | return 0; |
1da177e4 LT |
134 | } |
135 | ||
b74d24f7 | 136 | static int proc_getattr(struct mnt_idmap *idmap, |
549c7297 | 137 | const struct path *path, struct kstat *stat, |
a528d35e | 138 | u32 request_mask, unsigned int query_flags) |
2b579bee | 139 | { |
a528d35e | 140 | struct inode *inode = d_inode(path->dentry); |
6bee55f9 | 141 | struct proc_dir_entry *de = PDE(inode); |
e06689bf AD |
142 | if (de) { |
143 | nlink_t nlink = READ_ONCE(de->nlink); | |
144 | if (nlink > 0) { | |
145 | set_nlink(inode, nlink); | |
146 | } | |
147 | } | |
2b579bee | 148 | |
b74d24f7 | 149 | generic_fillattr(&nop_mnt_idmap, inode, stat); |
2b579bee MS |
150 | return 0; |
151 | } | |
152 | ||
c5ef1c42 | 153 | static const struct inode_operations proc_file_inode_operations = { |
1da177e4 LT |
154 | .setattr = proc_notify_change, |
155 | }; | |
156 | ||
157 | /* | |
158 | * This function parses a name such as "tty/driver/serial", and | |
159 | * returns the struct proc_dir_entry for "/proc/tty/driver", and | |
160 | * returns "serial" in residual. | |
161 | */ | |
e17a5765 AD |
162 | static int __xlate_proc_name(const char *name, struct proc_dir_entry **ret, |
163 | const char **residual) | |
1da177e4 LT |
164 | { |
165 | const char *cp = name, *next; | |
166 | struct proc_dir_entry *de; | |
1da177e4 | 167 | |
b793cd9a AD |
168 | de = *ret ?: &proc_root; |
169 | while ((next = strchr(cp, '/')) != NULL) { | |
5f6354ea | 170 | de = pde_subdir_find(de, cp, next - cp); |
12bac0d9 AD |
171 | if (!de) { |
172 | WARN(1, "name '%s'\n", name); | |
e17a5765 | 173 | return -ENOENT; |
12bac0d9 | 174 | } |
5f6354ea | 175 | cp = next + 1; |
1da177e4 LT |
176 | } |
177 | *residual = cp; | |
178 | *ret = de; | |
e17a5765 AD |
179 | return 0; |
180 | } | |
181 | ||
182 | static int xlate_proc_name(const char *name, struct proc_dir_entry **ret, | |
183 | const char **residual) | |
184 | { | |
185 | int rv; | |
186 | ||
ecf1a3df | 187 | read_lock(&proc_subdir_lock); |
e17a5765 | 188 | rv = __xlate_proc_name(name, ret, residual); |
ecf1a3df | 189 | read_unlock(&proc_subdir_lock); |
e17a5765 | 190 | return rv; |
1da177e4 LT |
191 | } |
192 | ||
9a185409 | 193 | static DEFINE_IDA(proc_inum_ida); |
1da177e4 | 194 | |
67935df4 | 195 | #define PROC_DYNAMIC_FIRST 0xF0000000U |
1da177e4 LT |
196 | |
197 | /* | |
198 | * Return an inode number between PROC_DYNAMIC_FIRST and | |
199 | * 0xffffffff, or zero on failure. | |
200 | */ | |
33d6dce6 | 201 | int proc_alloc_inum(unsigned int *inum) |
1da177e4 | 202 | { |
cde1b693 | 203 | int i; |
1da177e4 | 204 | |
cde1b693 HK |
205 | i = ida_simple_get(&proc_inum_ida, 0, UINT_MAX - PROC_DYNAMIC_FIRST + 1, |
206 | GFP_KERNEL); | |
207 | if (i < 0) | |
208 | return i; | |
1da177e4 | 209 | |
cde1b693 | 210 | *inum = PROC_DYNAMIC_FIRST + (unsigned int)i; |
33d6dce6 | 211 | return 0; |
1da177e4 LT |
212 | } |
213 | ||
33d6dce6 | 214 | void proc_free_inum(unsigned int inum) |
1da177e4 | 215 | { |
cde1b693 | 216 | ida_simple_remove(&proc_inum_ida, inum - PROC_DYNAMIC_FIRST); |
1da177e4 LT |
217 | } |
218 | ||
1da4d377 AD |
219 | static int proc_misc_d_revalidate(struct dentry *dentry, unsigned int flags) |
220 | { | |
221 | if (flags & LOOKUP_RCU) | |
222 | return -ECHILD; | |
223 | ||
224 | if (atomic_read(&PDE(d_inode(dentry))->in_use) < 0) | |
225 | return 0; /* revalidate */ | |
226 | return 1; | |
227 | } | |
228 | ||
229 | static int proc_misc_d_delete(const struct dentry *dentry) | |
230 | { | |
231 | return atomic_read(&PDE(d_inode(dentry))->in_use) < 0; | |
232 | } | |
233 | ||
234 | static const struct dentry_operations proc_misc_dentry_ops = { | |
235 | .d_revalidate = proc_misc_d_revalidate, | |
236 | .d_delete = proc_misc_d_delete, | |
237 | }; | |
238 | ||
1da177e4 LT |
239 | /* |
240 | * Don't create negative dentries here, return -ENOENT by hand | |
241 | * instead. | |
242 | */ | |
93ad5bc6 AD |
243 | struct dentry *proc_lookup_de(struct inode *dir, struct dentry *dentry, |
244 | struct proc_dir_entry *de) | |
1da177e4 | 245 | { |
d3d009cb | 246 | struct inode *inode; |
1da177e4 | 247 | |
ecf1a3df | 248 | read_lock(&proc_subdir_lock); |
710585d4 ND |
249 | de = pde_subdir_find(de, dentry->d_name.name, dentry->d_name.len); |
250 | if (de) { | |
251 | pde_get(de); | |
ecf1a3df | 252 | read_unlock(&proc_subdir_lock); |
710585d4 ND |
253 | inode = proc_get_inode(dir->i_sb, de); |
254 | if (!inode) | |
255 | return ERR_PTR(-ENOMEM); | |
1fde6f21 | 256 | d_set_d_op(dentry, de->proc_dops); |
888e2b03 | 257 | return d_splice_alias(inode, dentry); |
1da177e4 | 258 | } |
ecf1a3df | 259 | read_unlock(&proc_subdir_lock); |
d3d009cb | 260 | return ERR_PTR(-ENOENT); |
1da177e4 LT |
261 | } |
262 | ||
e9720acd | 263 | struct dentry *proc_lookup(struct inode *dir, struct dentry *dentry, |
00cd8dd3 | 264 | unsigned int flags) |
e9720acd | 265 | { |
6814ef2d AG |
266 | struct proc_fs_info *fs_info = proc_sb_info(dir->i_sb); |
267 | ||
268 | if (fs_info->pidonly == PROC_PIDONLY_ON) | |
269 | return ERR_PTR(-ENOENT); | |
270 | ||
93ad5bc6 | 271 | return proc_lookup_de(dir, dentry, PDE(dir)); |
e9720acd PE |
272 | } |
273 | ||
1da177e4 LT |
274 | /* |
275 | * This returns non-zero if at EOF, so that the /proc | |
276 | * root directory can use this and check if it should | |
277 | * continue with the <pid> entries.. | |
278 | * | |
279 | * Note that the VFS-layer doesn't care about the return | |
280 | * value of the readdir() call, as long as it's non-negative | |
281 | * for success.. | |
282 | */ | |
93ad5bc6 AD |
283 | int proc_readdir_de(struct file *file, struct dir_context *ctx, |
284 | struct proc_dir_entry *de) | |
1da177e4 | 285 | { |
1da177e4 | 286 | int i; |
f0c3b509 AV |
287 | |
288 | if (!dir_emit_dots(file, ctx)) | |
289 | return 0; | |
290 | ||
8d48b2e0 | 291 | i = ctx->pos - 2; |
ecf1a3df | 292 | read_lock(&proc_subdir_lock); |
710585d4 | 293 | de = pde_subdir_first(de); |
f0c3b509 AV |
294 | for (;;) { |
295 | if (!de) { | |
ecf1a3df | 296 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
297 | return 0; |
298 | } | |
299 | if (!i) | |
300 | break; | |
710585d4 | 301 | de = pde_subdir_next(de); |
f0c3b509 | 302 | i--; |
1da177e4 | 303 | } |
f0c3b509 AV |
304 | |
305 | do { | |
306 | struct proc_dir_entry *next; | |
307 | pde_get(de); | |
ecf1a3df | 308 | read_unlock(&proc_subdir_lock); |
f0c3b509 AV |
309 | if (!dir_emit(ctx, de->name, de->namelen, |
310 | de->low_ino, de->mode >> 12)) { | |
311 | pde_put(de); | |
312 | return 0; | |
313 | } | |
f0c3b509 | 314 | ctx->pos++; |
8d48b2e0 | 315 | read_lock(&proc_subdir_lock); |
710585d4 | 316 | next = pde_subdir_next(de); |
f0c3b509 AV |
317 | pde_put(de); |
318 | de = next; | |
319 | } while (de); | |
ecf1a3df | 320 | read_unlock(&proc_subdir_lock); |
fd3930f7 | 321 | return 1; |
1da177e4 LT |
322 | } |
323 | ||
f0c3b509 | 324 | int proc_readdir(struct file *file, struct dir_context *ctx) |
e9720acd | 325 | { |
f0c3b509 | 326 | struct inode *inode = file_inode(file); |
6814ef2d AG |
327 | struct proc_fs_info *fs_info = proc_sb_info(inode->i_sb); |
328 | ||
329 | if (fs_info->pidonly == PROC_PIDONLY_ON) | |
330 | return 1; | |
e9720acd | 331 | |
93ad5bc6 | 332 | return proc_readdir_de(file, ctx, PDE(inode)); |
e9720acd PE |
333 | } |
334 | ||
1da177e4 LT |
335 | /* |
336 | * These are the generic /proc directory operations. They | |
337 | * use the in-memory "struct proc_dir_entry" tree to parse | |
338 | * the /proc directory. | |
339 | */ | |
00977a59 | 340 | static const struct file_operations proc_dir_operations = { |
b4df2b92 | 341 | .llseek = generic_file_llseek, |
1da177e4 | 342 | .read = generic_read_dir, |
f50752ea | 343 | .iterate_shared = proc_readdir, |
1da177e4 LT |
344 | }; |
345 | ||
c6c75ded AD |
346 | static int proc_net_d_revalidate(struct dentry *dentry, unsigned int flags) |
347 | { | |
348 | return 0; | |
349 | } | |
350 | ||
351 | const struct dentry_operations proc_net_dentry_ops = { | |
352 | .d_revalidate = proc_net_d_revalidate, | |
353 | .d_delete = always_delete_dentry, | |
354 | }; | |
355 | ||
1da177e4 LT |
356 | /* |
357 | * proc directories can do almost nothing.. | |
358 | */ | |
c5ef1c42 | 359 | static const struct inode_operations proc_dir_inode_operations = { |
1da177e4 | 360 | .lookup = proc_lookup, |
2b579bee | 361 | .getattr = proc_getattr, |
1da177e4 LT |
362 | .setattr = proc_notify_change, |
363 | }; | |
364 | ||
61172eae CH |
365 | /* returns the registered entry, or frees dp and returns NULL on failure */ |
366 | struct proc_dir_entry *proc_register(struct proc_dir_entry *dir, | |
367 | struct proc_dir_entry *dp) | |
1da177e4 | 368 | { |
61172eae CH |
369 | if (proc_alloc_inum(&dp->low_ino)) |
370 | goto out_free_entry; | |
64a07bd8 | 371 | |
ecf1a3df | 372 | write_lock(&proc_subdir_lock); |
99fc06df | 373 | dp->parent = dir; |
b208d54b | 374 | if (pde_subdir_insert(dir, dp) == false) { |
710585d4 ND |
375 | WARN(1, "proc_dir_entry '%s/%s' already registered\n", |
376 | dir->name, dp->name); | |
ecf1a3df | 377 | write_unlock(&proc_subdir_lock); |
61172eae | 378 | goto out_free_inum; |
b208d54b | 379 | } |
e06689bf | 380 | dir->nlink++; |
ecf1a3df | 381 | write_unlock(&proc_subdir_lock); |
99fc06df | 382 | |
61172eae CH |
383 | return dp; |
384 | out_free_inum: | |
385 | proc_free_inum(dp->low_ino); | |
386 | out_free_entry: | |
387 | pde_free(dp); | |
388 | return NULL; | |
1da177e4 LT |
389 | } |
390 | ||
2d3a4e36 | 391 | static struct proc_dir_entry *__proc_create(struct proc_dir_entry **parent, |
1da177e4 | 392 | const char *name, |
d161a13f | 393 | umode_t mode, |
1da177e4 LT |
394 | nlink_t nlink) |
395 | { | |
396 | struct proc_dir_entry *ent = NULL; | |
dbcdb504 AD |
397 | const char *fn; |
398 | struct qstr qstr; | |
1da177e4 | 399 | |
7cee4e00 | 400 | if (xlate_proc_name(name, parent, &fn) != 0) |
1da177e4 | 401 | goto out; |
dbcdb504 AD |
402 | qstr.name = fn; |
403 | qstr.len = strlen(fn); | |
404 | if (qstr.len == 0 || qstr.len >= 256) { | |
405 | WARN(1, "name len %u\n", qstr.len); | |
406 | return NULL; | |
407 | } | |
b77d70db AD |
408 | if (qstr.len == 1 && fn[0] == '.') { |
409 | WARN(1, "name '.'\n"); | |
410 | return NULL; | |
411 | } | |
412 | if (qstr.len == 2 && fn[0] == '.' && fn[1] == '.') { | |
413 | WARN(1, "name '..'\n"); | |
414 | return NULL; | |
415 | } | |
dbcdb504 AD |
416 | if (*parent == &proc_root && name_to_int(&qstr) != ~0U) { |
417 | WARN(1, "create '/proc/%s' by hand\n", qstr.name); | |
418 | return NULL; | |
419 | } | |
eb6d38d5 EB |
420 | if (is_empty_pde(*parent)) { |
421 | WARN(1, "attempt to add to permanently empty directory"); | |
422 | return NULL; | |
423 | } | |
1da177e4 | 424 | |
b4884f23 | 425 | ent = kmem_cache_zalloc(proc_dir_entry_cache, GFP_KERNEL); |
17baa2a2 | 426 | if (!ent) |
427 | goto out; | |
1da177e4 | 428 | |
24074a35 | 429 | if (qstr.len + 1 <= SIZEOF_PDE_INLINE_NAME) { |
b4884f23 AD |
430 | ent->name = ent->inline_name; |
431 | } else { | |
432 | ent->name = kmalloc(qstr.len + 1, GFP_KERNEL); | |
433 | if (!ent->name) { | |
434 | pde_free(ent); | |
435 | return NULL; | |
436 | } | |
437 | } | |
438 | ||
dbcdb504 AD |
439 | memcpy(ent->name, fn, qstr.len + 1); |
440 | ent->namelen = qstr.len; | |
1da177e4 LT |
441 | ent->mode = mode; |
442 | ent->nlink = nlink; | |
4f113437 | 443 | ent->subdir = RB_ROOT; |
9cdd83e3 | 444 | refcount_set(&ent->refcnt, 1); |
786d7e16 | 445 | spin_lock_init(&ent->pde_unload_lock); |
881adb85 | 446 | INIT_LIST_HEAD(&ent->pde_openers); |
c110486f DT |
447 | proc_set_user(ent, (*parent)->uid, (*parent)->gid); |
448 | ||
1fde6f21 | 449 | ent->proc_dops = &proc_misc_dentry_ops; |
70551977 AD |
450 | /* Revalidate everything under /proc/${pid}/net */ |
451 | if ((*parent)->proc_dops == &proc_net_dentry_ops) | |
452 | pde_force_lookup(ent); | |
1fde6f21 | 453 | |
17baa2a2 | 454 | out: |
1da177e4 LT |
455 | return ent; |
456 | } | |
457 | ||
458 | struct proc_dir_entry *proc_symlink(const char *name, | |
459 | struct proc_dir_entry *parent, const char *dest) | |
460 | { | |
461 | struct proc_dir_entry *ent; | |
462 | ||
2d3a4e36 | 463 | ent = __proc_create(&parent, name, |
1da177e4 LT |
464 | (S_IFLNK | S_IRUGO | S_IWUGO | S_IXUGO),1); |
465 | ||
466 | if (ent) { | |
467 | ent->data = kmalloc((ent->size=strlen(dest))+1, GFP_KERNEL); | |
468 | if (ent->data) { | |
469 | strcpy((char*)ent->data,dest); | |
d443b9fd | 470 | ent->proc_iops = &proc_link_inode_operations; |
61172eae | 471 | ent = proc_register(parent, ent); |
1da177e4 | 472 | } else { |
b4884f23 | 473 | pde_free(ent); |
1da177e4 LT |
474 | ent = NULL; |
475 | } | |
476 | } | |
477 | return ent; | |
478 | } | |
587d4a17 | 479 | EXPORT_SYMBOL(proc_symlink); |
1da177e4 | 480 | |
c6c75ded AD |
481 | struct proc_dir_entry *_proc_mkdir(const char *name, umode_t mode, |
482 | struct proc_dir_entry *parent, void *data, bool force_lookup) | |
1da177e4 LT |
483 | { |
484 | struct proc_dir_entry *ent; | |
485 | ||
270b5ac2 DH |
486 | if (mode == 0) |
487 | mode = S_IRUGO | S_IXUGO; | |
488 | ||
2d3a4e36 | 489 | ent = __proc_create(&parent, name, S_IFDIR | mode, 2); |
1da177e4 | 490 | if (ent) { |
270b5ac2 | 491 | ent->data = data; |
d56c0d45 | 492 | ent->proc_dir_ops = &proc_dir_operations; |
d443b9fd | 493 | ent->proc_iops = &proc_dir_inode_operations; |
c6c75ded AD |
494 | if (force_lookup) { |
495 | pde_force_lookup(ent); | |
496 | } | |
61172eae | 497 | ent = proc_register(parent, ent); |
1da177e4 LT |
498 | } |
499 | return ent; | |
500 | } | |
c6c75ded AD |
501 | EXPORT_SYMBOL_GPL(_proc_mkdir); |
502 | ||
503 | struct proc_dir_entry *proc_mkdir_data(const char *name, umode_t mode, | |
504 | struct proc_dir_entry *parent, void *data) | |
505 | { | |
506 | return _proc_mkdir(name, mode, parent, data, false); | |
507 | } | |
270b5ac2 | 508 | EXPORT_SYMBOL_GPL(proc_mkdir_data); |
1da177e4 | 509 | |
270b5ac2 DH |
510 | struct proc_dir_entry *proc_mkdir_mode(const char *name, umode_t mode, |
511 | struct proc_dir_entry *parent) | |
78e92b99 | 512 | { |
270b5ac2 | 513 | return proc_mkdir_data(name, mode, parent, NULL); |
78e92b99 | 514 | } |
270b5ac2 | 515 | EXPORT_SYMBOL(proc_mkdir_mode); |
78e92b99 | 516 | |
1da177e4 LT |
517 | struct proc_dir_entry *proc_mkdir(const char *name, |
518 | struct proc_dir_entry *parent) | |
519 | { | |
270b5ac2 | 520 | return proc_mkdir_data(name, 0, parent, NULL); |
1da177e4 | 521 | } |
587d4a17 | 522 | EXPORT_SYMBOL(proc_mkdir); |
1da177e4 | 523 | |
eb6d38d5 EB |
524 | struct proc_dir_entry *proc_create_mount_point(const char *name) |
525 | { | |
526 | umode_t mode = S_IFDIR | S_IRUGO | S_IXUGO; | |
527 | struct proc_dir_entry *ent, *parent = NULL; | |
528 | ||
529 | ent = __proc_create(&parent, name, mode, 2); | |
530 | if (ent) { | |
531 | ent->data = NULL; | |
d56c0d45 | 532 | ent->proc_dir_ops = NULL; |
eb6d38d5 | 533 | ent->proc_iops = NULL; |
61172eae | 534 | ent = proc_register(parent, ent); |
eb6d38d5 EB |
535 | } |
536 | return ent; | |
537 | } | |
f97df70b | 538 | EXPORT_SYMBOL(proc_create_mount_point); |
eb6d38d5 | 539 | |
7aed53d1 CH |
540 | struct proc_dir_entry *proc_create_reg(const char *name, umode_t mode, |
541 | struct proc_dir_entry **parent, void *data) | |
2d3a4e36 | 542 | { |
7aed53d1 CH |
543 | struct proc_dir_entry *p; |
544 | ||
b6cdc731 AV |
545 | if ((mode & S_IFMT) == 0) |
546 | mode |= S_IFREG; | |
7aed53d1 CH |
547 | if ((mode & S_IALLUGO) == 0) |
548 | mode |= S_IRUGO; | |
549 | if (WARN_ON_ONCE(!S_ISREG(mode))) | |
b6cdc731 | 550 | return NULL; |
7aed53d1 CH |
551 | |
552 | p = __proc_create(parent, name, mode, 1); | |
553 | if (p) { | |
554 | p->proc_iops = &proc_file_inode_operations; | |
555 | p->data = data; | |
2d3a4e36 | 556 | } |
7aed53d1 CH |
557 | return p; |
558 | } | |
559 | ||
d919b33d AD |
560 | static inline void pde_set_flags(struct proc_dir_entry *pde) |
561 | { | |
562 | if (pde->proc_ops->proc_flags & PROC_ENTRY_PERMANENT) | |
563 | pde->flags |= PROC_ENTRY_PERMANENT; | |
564 | } | |
565 | ||
7aed53d1 CH |
566 | struct proc_dir_entry *proc_create_data(const char *name, umode_t mode, |
567 | struct proc_dir_entry *parent, | |
d56c0d45 | 568 | const struct proc_ops *proc_ops, void *data) |
7aed53d1 CH |
569 | { |
570 | struct proc_dir_entry *p; | |
2d3a4e36 | 571 | |
7aed53d1 CH |
572 | p = proc_create_reg(name, mode, &parent, data); |
573 | if (!p) | |
574 | return NULL; | |
d56c0d45 | 575 | p->proc_ops = proc_ops; |
d919b33d | 576 | pde_set_flags(p); |
7aed53d1 | 577 | return proc_register(parent, p); |
2d3a4e36 | 578 | } |
587d4a17 | 579 | EXPORT_SYMBOL(proc_create_data); |
271a15ea | 580 | |
855d9765 AD |
581 | struct proc_dir_entry *proc_create(const char *name, umode_t mode, |
582 | struct proc_dir_entry *parent, | |
d56c0d45 | 583 | const struct proc_ops *proc_ops) |
855d9765 | 584 | { |
d56c0d45 | 585 | return proc_create_data(name, mode, parent, proc_ops, NULL); |
855d9765 AD |
586 | } |
587 | EXPORT_SYMBOL(proc_create); | |
588 | ||
fddda2b7 CH |
589 | static int proc_seq_open(struct inode *inode, struct file *file) |
590 | { | |
591 | struct proc_dir_entry *de = PDE(inode); | |
592 | ||
44414d82 CH |
593 | if (de->state_size) |
594 | return seq_open_private(file, de->seq_ops, de->state_size); | |
fddda2b7 CH |
595 | return seq_open(file, de->seq_ops); |
596 | } | |
597 | ||
877f919e CH |
598 | static int proc_seq_release(struct inode *inode, struct file *file) |
599 | { | |
600 | struct proc_dir_entry *de = PDE(inode); | |
601 | ||
602 | if (de->state_size) | |
603 | return seq_release_private(inode, file); | |
604 | return seq_release(inode, file); | |
605 | } | |
606 | ||
d56c0d45 | 607 | static const struct proc_ops proc_seq_ops = { |
d919b33d | 608 | /* not permanent -- can call into arbitrary seq_operations */ |
d56c0d45 | 609 | .proc_open = proc_seq_open, |
b24c30c6 | 610 | .proc_read_iter = seq_read_iter, |
d56c0d45 AD |
611 | .proc_lseek = seq_lseek, |
612 | .proc_release = proc_seq_release, | |
fddda2b7 CH |
613 | }; |
614 | ||
44414d82 | 615 | struct proc_dir_entry *proc_create_seq_private(const char *name, umode_t mode, |
fddda2b7 | 616 | struct proc_dir_entry *parent, const struct seq_operations *ops, |
44414d82 | 617 | unsigned int state_size, void *data) |
fddda2b7 CH |
618 | { |
619 | struct proc_dir_entry *p; | |
620 | ||
621 | p = proc_create_reg(name, mode, &parent, data); | |
622 | if (!p) | |
623 | return NULL; | |
d56c0d45 | 624 | p->proc_ops = &proc_seq_ops; |
fddda2b7 | 625 | p->seq_ops = ops; |
44414d82 | 626 | p->state_size = state_size; |
fddda2b7 CH |
627 | return proc_register(parent, p); |
628 | } | |
44414d82 | 629 | EXPORT_SYMBOL(proc_create_seq_private); |
fddda2b7 | 630 | |
3f3942ac CH |
631 | static int proc_single_open(struct inode *inode, struct file *file) |
632 | { | |
633 | struct proc_dir_entry *de = PDE(inode); | |
634 | ||
635 | return single_open(file, de->single_show, de->data); | |
636 | } | |
637 | ||
d56c0d45 | 638 | static const struct proc_ops proc_single_ops = { |
d919b33d | 639 | /* not permanent -- can call into arbitrary ->single_show */ |
d56c0d45 | 640 | .proc_open = proc_single_open, |
7cfc630e | 641 | .proc_read_iter = seq_read_iter, |
d56c0d45 AD |
642 | .proc_lseek = seq_lseek, |
643 | .proc_release = single_release, | |
3f3942ac CH |
644 | }; |
645 | ||
646 | struct proc_dir_entry *proc_create_single_data(const char *name, umode_t mode, | |
647 | struct proc_dir_entry *parent, | |
648 | int (*show)(struct seq_file *, void *), void *data) | |
649 | { | |
650 | struct proc_dir_entry *p; | |
651 | ||
652 | p = proc_create_reg(name, mode, &parent, data); | |
653 | if (!p) | |
654 | return NULL; | |
d56c0d45 | 655 | p->proc_ops = &proc_single_ops; |
3f3942ac CH |
656 | p->single_show = show; |
657 | return proc_register(parent, p); | |
658 | } | |
659 | EXPORT_SYMBOL(proc_create_single_data); | |
660 | ||
271a15ea DH |
661 | void proc_set_size(struct proc_dir_entry *de, loff_t size) |
662 | { | |
663 | de->size = size; | |
664 | } | |
665 | EXPORT_SYMBOL(proc_set_size); | |
666 | ||
667 | void proc_set_user(struct proc_dir_entry *de, kuid_t uid, kgid_t gid) | |
668 | { | |
669 | de->uid = uid; | |
670 | de->gid = gid; | |
671 | } | |
672 | EXPORT_SYMBOL(proc_set_user); | |
2d3a4e36 | 673 | |
135d5655 AD |
674 | void pde_put(struct proc_dir_entry *pde) |
675 | { | |
9cdd83e3 | 676 | if (refcount_dec_and_test(&pde->refcnt)) { |
b4884f23 AD |
677 | proc_free_inum(pde->low_ino); |
678 | pde_free(pde); | |
679 | } | |
135d5655 AD |
680 | } |
681 | ||
8ce584c7 AV |
682 | /* |
683 | * Remove a /proc entry and free it if it's not currently in use. | |
684 | */ | |
685 | void remove_proc_entry(const char *name, struct proc_dir_entry *parent) | |
686 | { | |
8ce584c7 AV |
687 | struct proc_dir_entry *de = NULL; |
688 | const char *fn = name; | |
689 | unsigned int len; | |
690 | ||
ecf1a3df | 691 | write_lock(&proc_subdir_lock); |
8ce584c7 | 692 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 693 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
694 | return; |
695 | } | |
696 | len = strlen(fn); | |
697 | ||
710585d4 | 698 | de = pde_subdir_find(parent, fn, len); |
e06689bf | 699 | if (de) { |
d919b33d AD |
700 | if (unlikely(pde_is_permanent(de))) { |
701 | WARN(1, "removing permanent /proc entry '%s'", de->name); | |
702 | de = NULL; | |
703 | } else { | |
704 | rb_erase(&de->subdir_node, &parent->subdir); | |
705 | if (S_ISDIR(de->mode)) | |
706 | parent->nlink--; | |
e06689bf AD |
707 | } |
708 | } | |
ecf1a3df | 709 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
710 | if (!de) { |
711 | WARN(1, "name '%s'\n", name); | |
712 | return; | |
713 | } | |
714 | ||
866ad9a7 | 715 | proc_entry_rundown(de); |
881adb85 | 716 | |
710585d4 ND |
717 | WARN(pde_subdir_first(de), |
718 | "%s: removing non-empty directory '%s/%s', leaking at least '%s'\n", | |
719 | __func__, de->parent->name, de->name, pde_subdir_first(de)->name); | |
135d5655 | 720 | pde_put(de); |
1da177e4 | 721 | } |
587d4a17 | 722 | EXPORT_SYMBOL(remove_proc_entry); |
8ce584c7 AV |
723 | |
724 | int remove_proc_subtree(const char *name, struct proc_dir_entry *parent) | |
725 | { | |
8ce584c7 AV |
726 | struct proc_dir_entry *root = NULL, *de, *next; |
727 | const char *fn = name; | |
728 | unsigned int len; | |
729 | ||
ecf1a3df | 730 | write_lock(&proc_subdir_lock); |
8ce584c7 | 731 | if (__xlate_proc_name(name, &parent, &fn) != 0) { |
ecf1a3df | 732 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
733 | return -ENOENT; |
734 | } | |
735 | len = strlen(fn); | |
736 | ||
710585d4 | 737 | root = pde_subdir_find(parent, fn, len); |
8ce584c7 | 738 | if (!root) { |
ecf1a3df | 739 | write_unlock(&proc_subdir_lock); |
8ce584c7 AV |
740 | return -ENOENT; |
741 | } | |
d919b33d AD |
742 | if (unlikely(pde_is_permanent(root))) { |
743 | write_unlock(&proc_subdir_lock); | |
744 | WARN(1, "removing permanent /proc entry '%s/%s'", | |
745 | root->parent->name, root->name); | |
746 | return -EINVAL; | |
747 | } | |
4f113437 | 748 | rb_erase(&root->subdir_node, &parent->subdir); |
710585d4 | 749 | |
8ce584c7 AV |
750 | de = root; |
751 | while (1) { | |
710585d4 | 752 | next = pde_subdir_first(de); |
8ce584c7 | 753 | if (next) { |
f4bf74d8 | 754 | if (unlikely(pde_is_permanent(next))) { |
d919b33d AD |
755 | write_unlock(&proc_subdir_lock); |
756 | WARN(1, "removing permanent /proc entry '%s/%s'", | |
757 | next->parent->name, next->name); | |
758 | return -EINVAL; | |
759 | } | |
4f113437 | 760 | rb_erase(&next->subdir_node, &de->subdir); |
8ce584c7 AV |
761 | de = next; |
762 | continue; | |
763 | } | |
8ce584c7 AV |
764 | next = de->parent; |
765 | if (S_ISDIR(de->mode)) | |
766 | next->nlink--; | |
e06689bf AD |
767 | write_unlock(&proc_subdir_lock); |
768 | ||
769 | proc_entry_rundown(de); | |
8ce584c7 AV |
770 | if (de == root) |
771 | break; | |
772 | pde_put(de); | |
773 | ||
ecf1a3df | 774 | write_lock(&proc_subdir_lock); |
8ce584c7 AV |
775 | de = next; |
776 | } | |
777 | pde_put(root); | |
778 | return 0; | |
779 | } | |
780 | EXPORT_SYMBOL(remove_proc_subtree); | |
4a520d27 DH |
781 | |
782 | void *proc_get_parent_data(const struct inode *inode) | |
783 | { | |
784 | struct proc_dir_entry *de = PDE(inode); | |
785 | return de->parent->data; | |
786 | } | |
787 | EXPORT_SYMBOL_GPL(proc_get_parent_data); | |
a8ca16ea DH |
788 | |
789 | void proc_remove(struct proc_dir_entry *de) | |
790 | { | |
791 | if (de) | |
792 | remove_proc_subtree(de->name, de->parent); | |
793 | } | |
794 | EXPORT_SYMBOL(proc_remove); | |
c30480b9 | 795 | |
564def71 DH |
796 | /* |
797 | * Pull a user buffer into memory and pass it to the file's write handler if | |
798 | * one is supplied. The ->write() method is permitted to modify the | |
799 | * kernel-side buffer. | |
800 | */ | |
801 | ssize_t proc_simple_write(struct file *f, const char __user *ubuf, size_t size, | |
802 | loff_t *_pos) | |
803 | { | |
804 | struct proc_dir_entry *pde = PDE(file_inode(f)); | |
805 | char *buf; | |
806 | int ret; | |
807 | ||
808 | if (!pde->write) | |
809 | return -EACCES; | |
810 | if (size == 0 || size > PAGE_SIZE - 1) | |
811 | return -EINVAL; | |
812 | buf = memdup_user_nul(ubuf, size); | |
813 | if (IS_ERR(buf)) | |
814 | return PTR_ERR(buf); | |
815 | ret = pde->write(f, buf, size); | |
816 | kfree(buf); | |
817 | return ret == 0 ? size : ret; | |
818 | } |