Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * POSIX message queues filesystem for Linux. | |
3 | * | |
4 | * Copyright (C) 2003,2004 Krzysztof Benedyczak (golbi@mat.uni.torun.pl) | |
f66e928b | 5 | * Michal Wronski (michal.wronski@gmail.com) |
1da177e4 LT |
6 | * |
7 | * Spinlocks: Mohamed Abbas (abbas.mohamed@intel.com) | |
8 | * Lockless receive & send, fd based notify: | |
9 | * Manfred Spraul (manfred@colorfullife.com) | |
10 | * | |
20ca73bc GW |
11 | * Audit: George Wilson (ltcgcw@us.ibm.com) |
12 | * | |
1da177e4 LT |
13 | * This file is released under the GPL. |
14 | */ | |
15 | ||
c59ede7b | 16 | #include <linux/capability.h> |
1da177e4 LT |
17 | #include <linux/init.h> |
18 | #include <linux/pagemap.h> | |
19 | #include <linux/file.h> | |
20 | #include <linux/mount.h> | |
21 | #include <linux/namei.h> | |
22 | #include <linux/sysctl.h> | |
23 | #include <linux/poll.h> | |
24 | #include <linux/mqueue.h> | |
25 | #include <linux/msg.h> | |
26 | #include <linux/skbuff.h> | |
27 | #include <linux/netlink.h> | |
28 | #include <linux/syscalls.h> | |
20ca73bc | 29 | #include <linux/audit.h> |
7ed20e1a | 30 | #include <linux/signal.h> |
5f921ae9 | 31 | #include <linux/mutex.h> |
b488893a PE |
32 | #include <linux/nsproxy.h> |
33 | #include <linux/pid.h> | |
614b84cf | 34 | #include <linux/ipc_namespace.h> |
46690f37 | 35 | #include <linux/ima.h> |
5f921ae9 | 36 | |
1da177e4 LT |
37 | #include <net/sock.h> |
38 | #include "util.h" | |
39 | ||
40 | #define MQUEUE_MAGIC 0x19800202 | |
41 | #define DIRENT_SIZE 20 | |
42 | #define FILENT_SIZE 80 | |
43 | ||
44 | #define SEND 0 | |
45 | #define RECV 1 | |
46 | ||
47 | #define STATE_NONE 0 | |
48 | #define STATE_PENDING 1 | |
49 | #define STATE_READY 2 | |
50 | ||
1da177e4 LT |
51 | struct ext_wait_queue { /* queue of sleeping tasks */ |
52 | struct task_struct *task; | |
53 | struct list_head list; | |
54 | struct msg_msg *msg; /* ptr of loaded message */ | |
55 | int state; /* one of STATE_* values */ | |
56 | }; | |
57 | ||
58 | struct mqueue_inode_info { | |
59 | spinlock_t lock; | |
60 | struct inode vfs_inode; | |
61 | wait_queue_head_t wait_q; | |
62 | ||
63 | struct msg_msg **messages; | |
64 | struct mq_attr attr; | |
65 | ||
66 | struct sigevent notify; | |
a03fcb73 | 67 | struct pid* notify_owner; |
338cec32 | 68 | struct user_struct *user; /* user who created, for accounting */ |
1da177e4 LT |
69 | struct sock *notify_sock; |
70 | struct sk_buff *notify_cookie; | |
71 | ||
72 | /* for tasks waiting for free space and messages, respectively */ | |
73 | struct ext_wait_queue e_wait_q[2]; | |
74 | ||
75 | unsigned long qsize; /* size of queue in memory (sum of all msgs) */ | |
76 | }; | |
77 | ||
92e1d5be | 78 | static const struct inode_operations mqueue_dir_inode_operations; |
9a32144e | 79 | static const struct file_operations mqueue_file_operations; |
1da177e4 LT |
80 | static struct super_operations mqueue_super_ops; |
81 | static void remove_notification(struct mqueue_inode_info *info); | |
82 | ||
e18b890b | 83 | static struct kmem_cache *mqueue_inode_cachep; |
1da177e4 LT |
84 | |
85 | static struct ctl_table_header * mq_sysctl_table; | |
86 | ||
87 | static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode) | |
88 | { | |
89 | return container_of(inode, struct mqueue_inode_info, vfs_inode); | |
90 | } | |
91 | ||
7eafd7c7 SH |
92 | /* |
93 | * This routine should be called with the mq_lock held. | |
94 | */ | |
95 | static inline struct ipc_namespace *__get_ns_from_inode(struct inode *inode) | |
614b84cf | 96 | { |
7eafd7c7 | 97 | return get_ipc_ns(inode->i_sb->s_fs_info); |
614b84cf SH |
98 | } |
99 | ||
7eafd7c7 | 100 | static struct ipc_namespace *get_ns_from_inode(struct inode *inode) |
614b84cf | 101 | { |
7eafd7c7 SH |
102 | struct ipc_namespace *ns; |
103 | ||
104 | spin_lock(&mq_lock); | |
105 | ns = __get_ns_from_inode(inode); | |
106 | spin_unlock(&mq_lock); | |
107 | return ns; | |
614b84cf SH |
108 | } |
109 | ||
7eafd7c7 SH |
110 | static struct inode *mqueue_get_inode(struct super_block *sb, |
111 | struct ipc_namespace *ipc_ns, int mode, | |
112 | struct mq_attr *attr) | |
1da177e4 | 113 | { |
86a264ab | 114 | struct user_struct *u = current_user(); |
1da177e4 LT |
115 | struct inode *inode; |
116 | ||
117 | inode = new_inode(sb); | |
118 | if (inode) { | |
119 | inode->i_mode = mode; | |
414c0708 DH |
120 | inode->i_uid = current_fsuid(); |
121 | inode->i_gid = current_fsgid(); | |
1da177e4 LT |
122 | inode->i_mtime = inode->i_ctime = inode->i_atime = |
123 | CURRENT_TIME; | |
124 | ||
125 | if (S_ISREG(mode)) { | |
126 | struct mqueue_inode_info *info; | |
127 | struct task_struct *p = current; | |
1da177e4 LT |
128 | unsigned long mq_bytes, mq_msg_tblsz; |
129 | ||
130 | inode->i_fop = &mqueue_file_operations; | |
131 | inode->i_size = FILENT_SIZE; | |
132 | /* mqueue specific info */ | |
133 | info = MQUEUE_I(inode); | |
134 | spin_lock_init(&info->lock); | |
135 | init_waitqueue_head(&info->wait_q); | |
136 | INIT_LIST_HEAD(&info->e_wait_q[0].list); | |
137 | INIT_LIST_HEAD(&info->e_wait_q[1].list); | |
138 | info->messages = NULL; | |
a03fcb73 | 139 | info->notify_owner = NULL; |
1da177e4 LT |
140 | info->qsize = 0; |
141 | info->user = NULL; /* set when all is ok */ | |
142 | memset(&info->attr, 0, sizeof(info->attr)); | |
614b84cf SH |
143 | info->attr.mq_maxmsg = ipc_ns->mq_msg_max; |
144 | info->attr.mq_msgsize = ipc_ns->mq_msgsize_max; | |
1da177e4 LT |
145 | if (attr) { |
146 | info->attr.mq_maxmsg = attr->mq_maxmsg; | |
147 | info->attr.mq_msgsize = attr->mq_msgsize; | |
148 | } | |
149 | mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *); | |
150 | mq_bytes = (mq_msg_tblsz + | |
151 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); | |
152 | ||
153 | spin_lock(&mq_lock); | |
154 | if (u->mq_bytes + mq_bytes < u->mq_bytes || | |
155 | u->mq_bytes + mq_bytes > | |
156 | p->signal->rlim[RLIMIT_MSGQUEUE].rlim_cur) { | |
157 | spin_unlock(&mq_lock); | |
158 | goto out_inode; | |
159 | } | |
160 | u->mq_bytes += mq_bytes; | |
161 | spin_unlock(&mq_lock); | |
162 | ||
163 | info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL); | |
164 | if (!info->messages) { | |
165 | spin_lock(&mq_lock); | |
166 | u->mq_bytes -= mq_bytes; | |
167 | spin_unlock(&mq_lock); | |
168 | goto out_inode; | |
169 | } | |
170 | /* all is ok */ | |
171 | info->user = get_uid(u); | |
172 | } else if (S_ISDIR(mode)) { | |
d8c76e6f | 173 | inc_nlink(inode); |
1da177e4 LT |
174 | /* Some things misbehave if size == 0 on a directory */ |
175 | inode->i_size = 2 * DIRENT_SIZE; | |
176 | inode->i_op = &mqueue_dir_inode_operations; | |
177 | inode->i_fop = &simple_dir_operations; | |
178 | } | |
179 | } | |
180 | return inode; | |
181 | out_inode: | |
182 | make_bad_inode(inode); | |
183 | iput(inode); | |
184 | return NULL; | |
185 | } | |
186 | ||
187 | static int mqueue_fill_super(struct super_block *sb, void *data, int silent) | |
188 | { | |
189 | struct inode *inode; | |
7eafd7c7 SH |
190 | struct ipc_namespace *ns = data; |
191 | int error = 0; | |
1da177e4 LT |
192 | |
193 | sb->s_blocksize = PAGE_CACHE_SIZE; | |
194 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; | |
195 | sb->s_magic = MQUEUE_MAGIC; | |
196 | sb->s_op = &mqueue_super_ops; | |
197 | ||
7eafd7c7 SH |
198 | inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO, |
199 | NULL); | |
200 | if (!inode) { | |
201 | error = -ENOMEM; | |
202 | goto out; | |
203 | } | |
1da177e4 LT |
204 | |
205 | sb->s_root = d_alloc_root(inode); | |
206 | if (!sb->s_root) { | |
207 | iput(inode); | |
7eafd7c7 | 208 | error = -ENOMEM; |
1da177e4 LT |
209 | } |
210 | ||
7eafd7c7 SH |
211 | out: |
212 | return error; | |
1da177e4 LT |
213 | } |
214 | ||
454e2398 DH |
215 | static int mqueue_get_sb(struct file_system_type *fs_type, |
216 | int flags, const char *dev_name, | |
217 | void *data, struct vfsmount *mnt) | |
1da177e4 | 218 | { |
7eafd7c7 SH |
219 | if (!(flags & MS_KERNMOUNT)) |
220 | data = current->nsproxy->ipc_ns; | |
221 | return get_sb_ns(fs_type, flags, data, mqueue_fill_super, mnt); | |
1da177e4 LT |
222 | } |
223 | ||
51cc5068 | 224 | static void init_once(void *foo) |
1da177e4 LT |
225 | { |
226 | struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo; | |
227 | ||
a35afb83 | 228 | inode_init_once(&p->vfs_inode); |
1da177e4 LT |
229 | } |
230 | ||
231 | static struct inode *mqueue_alloc_inode(struct super_block *sb) | |
232 | { | |
233 | struct mqueue_inode_info *ei; | |
234 | ||
e94b1766 | 235 | ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL); |
1da177e4 LT |
236 | if (!ei) |
237 | return NULL; | |
238 | return &ei->vfs_inode; | |
239 | } | |
240 | ||
241 | static void mqueue_destroy_inode(struct inode *inode) | |
242 | { | |
243 | kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode)); | |
244 | } | |
245 | ||
246 | static void mqueue_delete_inode(struct inode *inode) | |
247 | { | |
248 | struct mqueue_inode_info *info; | |
249 | struct user_struct *user; | |
250 | unsigned long mq_bytes; | |
251 | int i; | |
7eafd7c7 | 252 | struct ipc_namespace *ipc_ns; |
1da177e4 LT |
253 | |
254 | if (S_ISDIR(inode->i_mode)) { | |
255 | clear_inode(inode); | |
256 | return; | |
257 | } | |
7eafd7c7 | 258 | ipc_ns = get_ns_from_inode(inode); |
1da177e4 LT |
259 | info = MQUEUE_I(inode); |
260 | spin_lock(&info->lock); | |
261 | for (i = 0; i < info->attr.mq_curmsgs; i++) | |
262 | free_msg(info->messages[i]); | |
263 | kfree(info->messages); | |
264 | spin_unlock(&info->lock); | |
265 | ||
266 | clear_inode(inode); | |
267 | ||
268 | mq_bytes = (info->attr.mq_maxmsg * sizeof(struct msg_msg *) + | |
269 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); | |
270 | user = info->user; | |
271 | if (user) { | |
272 | spin_lock(&mq_lock); | |
273 | user->mq_bytes -= mq_bytes; | |
7eafd7c7 SH |
274 | /* |
275 | * get_ns_from_inode() ensures that the | |
276 | * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns | |
277 | * to which we now hold a reference, or it is NULL. | |
278 | * We can't put it here under mq_lock, though. | |
279 | */ | |
280 | if (ipc_ns) | |
281 | ipc_ns->mq_queues_count--; | |
1da177e4 LT |
282 | spin_unlock(&mq_lock); |
283 | free_uid(user); | |
284 | } | |
7eafd7c7 SH |
285 | if (ipc_ns) |
286 | put_ipc_ns(ipc_ns); | |
1da177e4 LT |
287 | } |
288 | ||
289 | static int mqueue_create(struct inode *dir, struct dentry *dentry, | |
290 | int mode, struct nameidata *nd) | |
291 | { | |
292 | struct inode *inode; | |
293 | struct mq_attr *attr = dentry->d_fsdata; | |
294 | int error; | |
7eafd7c7 | 295 | struct ipc_namespace *ipc_ns; |
1da177e4 LT |
296 | |
297 | spin_lock(&mq_lock); | |
7eafd7c7 SH |
298 | ipc_ns = __get_ns_from_inode(dir); |
299 | if (!ipc_ns) { | |
300 | error = -EACCES; | |
301 | goto out_unlock; | |
302 | } | |
614b84cf SH |
303 | if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max && |
304 | !capable(CAP_SYS_RESOURCE)) { | |
1da177e4 | 305 | error = -ENOSPC; |
614b84cf | 306 | goto out_unlock; |
1da177e4 | 307 | } |
614b84cf | 308 | ipc_ns->mq_queues_count++; |
1da177e4 LT |
309 | spin_unlock(&mq_lock); |
310 | ||
7eafd7c7 | 311 | inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr); |
1da177e4 LT |
312 | if (!inode) { |
313 | error = -ENOMEM; | |
314 | spin_lock(&mq_lock); | |
614b84cf SH |
315 | ipc_ns->mq_queues_count--; |
316 | goto out_unlock; | |
1da177e4 LT |
317 | } |
318 | ||
7eafd7c7 | 319 | put_ipc_ns(ipc_ns); |
1da177e4 LT |
320 | dir->i_size += DIRENT_SIZE; |
321 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
322 | ||
323 | d_instantiate(dentry, inode); | |
324 | dget(dentry); | |
325 | return 0; | |
614b84cf | 326 | out_unlock: |
1da177e4 | 327 | spin_unlock(&mq_lock); |
7eafd7c7 SH |
328 | if (ipc_ns) |
329 | put_ipc_ns(ipc_ns); | |
1da177e4 LT |
330 | return error; |
331 | } | |
332 | ||
333 | static int mqueue_unlink(struct inode *dir, struct dentry *dentry) | |
334 | { | |
335 | struct inode *inode = dentry->d_inode; | |
336 | ||
337 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
338 | dir->i_size -= DIRENT_SIZE; | |
9a53c3a7 | 339 | drop_nlink(inode); |
1da177e4 LT |
340 | dput(dentry); |
341 | return 0; | |
342 | } | |
343 | ||
344 | /* | |
345 | * This is routine for system read from queue file. | |
346 | * To avoid mess with doing here some sort of mq_receive we allow | |
347 | * to read only queue size & notification info (the only values | |
348 | * that are interesting from user point of view and aren't accessible | |
349 | * through std routines) | |
350 | */ | |
351 | static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, | |
f1a43f93 | 352 | size_t count, loff_t *off) |
1da177e4 | 353 | { |
6d63079a | 354 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 | 355 | char buffer[FILENT_SIZE]; |
f1a43f93 | 356 | ssize_t ret; |
1da177e4 LT |
357 | |
358 | spin_lock(&info->lock); | |
359 | snprintf(buffer, sizeof(buffer), | |
360 | "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n", | |
361 | info->qsize, | |
362 | info->notify_owner ? info->notify.sigev_notify : 0, | |
363 | (info->notify_owner && | |
364 | info->notify.sigev_notify == SIGEV_SIGNAL) ? | |
365 | info->notify.sigev_signo : 0, | |
6c5f3e7b | 366 | pid_vnr(info->notify_owner)); |
1da177e4 LT |
367 | spin_unlock(&info->lock); |
368 | buffer[sizeof(buffer)-1] = '\0'; | |
1da177e4 | 369 | |
f1a43f93 AM |
370 | ret = simple_read_from_buffer(u_data, count, off, buffer, |
371 | strlen(buffer)); | |
372 | if (ret <= 0) | |
373 | return ret; | |
1da177e4 | 374 | |
6d63079a | 375 | filp->f_path.dentry->d_inode->i_atime = filp->f_path.dentry->d_inode->i_ctime = CURRENT_TIME; |
f1a43f93 | 376 | return ret; |
1da177e4 LT |
377 | } |
378 | ||
75e1fcc0 | 379 | static int mqueue_flush_file(struct file *filp, fl_owner_t id) |
1da177e4 | 380 | { |
6d63079a | 381 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
382 | |
383 | spin_lock(&info->lock); | |
a03fcb73 | 384 | if (task_tgid(current) == info->notify_owner) |
1da177e4 LT |
385 | remove_notification(info); |
386 | ||
387 | spin_unlock(&info->lock); | |
388 | return 0; | |
389 | } | |
390 | ||
391 | static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab) | |
392 | { | |
6d63079a | 393 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
394 | int retval = 0; |
395 | ||
396 | poll_wait(filp, &info->wait_q, poll_tab); | |
397 | ||
398 | spin_lock(&info->lock); | |
399 | if (info->attr.mq_curmsgs) | |
400 | retval = POLLIN | POLLRDNORM; | |
401 | ||
402 | if (info->attr.mq_curmsgs < info->attr.mq_maxmsg) | |
403 | retval |= POLLOUT | POLLWRNORM; | |
404 | spin_unlock(&info->lock); | |
405 | ||
406 | return retval; | |
407 | } | |
408 | ||
409 | /* Adds current to info->e_wait_q[sr] before element with smaller prio */ | |
410 | static void wq_add(struct mqueue_inode_info *info, int sr, | |
411 | struct ext_wait_queue *ewp) | |
412 | { | |
413 | struct ext_wait_queue *walk; | |
414 | ||
415 | ewp->task = current; | |
416 | ||
417 | list_for_each_entry(walk, &info->e_wait_q[sr].list, list) { | |
418 | if (walk->task->static_prio <= current->static_prio) { | |
419 | list_add_tail(&ewp->list, &walk->list); | |
420 | return; | |
421 | } | |
422 | } | |
423 | list_add_tail(&ewp->list, &info->e_wait_q[sr].list); | |
424 | } | |
425 | ||
426 | /* | |
427 | * Puts current task to sleep. Caller must hold queue lock. After return | |
428 | * lock isn't held. | |
429 | * sr: SEND or RECV | |
430 | */ | |
431 | static int wq_sleep(struct mqueue_inode_info *info, int sr, | |
432 | long timeout, struct ext_wait_queue *ewp) | |
433 | { | |
434 | int retval; | |
435 | signed long time; | |
436 | ||
437 | wq_add(info, sr, ewp); | |
438 | ||
439 | for (;;) { | |
440 | set_current_state(TASK_INTERRUPTIBLE); | |
441 | ||
442 | spin_unlock(&info->lock); | |
443 | time = schedule_timeout(timeout); | |
444 | ||
445 | while (ewp->state == STATE_PENDING) | |
446 | cpu_relax(); | |
447 | ||
448 | if (ewp->state == STATE_READY) { | |
449 | retval = 0; | |
450 | goto out; | |
451 | } | |
452 | spin_lock(&info->lock); | |
453 | if (ewp->state == STATE_READY) { | |
454 | retval = 0; | |
455 | goto out_unlock; | |
456 | } | |
457 | if (signal_pending(current)) { | |
458 | retval = -ERESTARTSYS; | |
459 | break; | |
460 | } | |
461 | if (time == 0) { | |
462 | retval = -ETIMEDOUT; | |
463 | break; | |
464 | } | |
465 | } | |
466 | list_del(&ewp->list); | |
467 | out_unlock: | |
468 | spin_unlock(&info->lock); | |
469 | out: | |
470 | return retval; | |
471 | } | |
472 | ||
473 | /* | |
474 | * Returns waiting task that should be serviced first or NULL if none exists | |
475 | */ | |
476 | static struct ext_wait_queue *wq_get_first_waiter( | |
477 | struct mqueue_inode_info *info, int sr) | |
478 | { | |
479 | struct list_head *ptr; | |
480 | ||
481 | ptr = info->e_wait_q[sr].list.prev; | |
482 | if (ptr == &info->e_wait_q[sr].list) | |
483 | return NULL; | |
484 | return list_entry(ptr, struct ext_wait_queue, list); | |
485 | } | |
486 | ||
487 | /* Auxiliary functions to manipulate messages' list */ | |
488 | static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info) | |
489 | { | |
490 | int k; | |
491 | ||
492 | k = info->attr.mq_curmsgs - 1; | |
493 | while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) { | |
494 | info->messages[k + 1] = info->messages[k]; | |
495 | k--; | |
496 | } | |
497 | info->attr.mq_curmsgs++; | |
498 | info->qsize += ptr->m_ts; | |
499 | info->messages[k + 1] = ptr; | |
500 | } | |
501 | ||
502 | static inline struct msg_msg *msg_get(struct mqueue_inode_info *info) | |
503 | { | |
504 | info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts; | |
505 | return info->messages[info->attr.mq_curmsgs]; | |
506 | } | |
507 | ||
508 | static inline void set_cookie(struct sk_buff *skb, char code) | |
509 | { | |
510 | ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code; | |
511 | } | |
512 | ||
513 | /* | |
514 | * The next function is only to split too long sys_mq_timedsend | |
515 | */ | |
516 | static void __do_notify(struct mqueue_inode_info *info) | |
517 | { | |
518 | /* notification | |
519 | * invoked when there is registered process and there isn't process | |
520 | * waiting synchronously for message AND state of queue changed from | |
521 | * empty to not empty. Here we are sure that no one is waiting | |
522 | * synchronously. */ | |
523 | if (info->notify_owner && | |
524 | info->attr.mq_curmsgs == 1) { | |
525 | struct siginfo sig_i; | |
526 | switch (info->notify.sigev_notify) { | |
527 | case SIGEV_NONE: | |
528 | break; | |
529 | case SIGEV_SIGNAL: | |
530 | /* sends signal */ | |
531 | ||
532 | sig_i.si_signo = info->notify.sigev_signo; | |
533 | sig_i.si_errno = 0; | |
534 | sig_i.si_code = SI_MESGQ; | |
535 | sig_i.si_value = info->notify.sigev_value; | |
a6684999 SB |
536 | sig_i.si_pid = task_tgid_nr_ns(current, |
537 | ns_of_pid(info->notify_owner)); | |
414c0708 | 538 | sig_i.si_uid = current_uid(); |
1da177e4 | 539 | |
a03fcb73 CLG |
540 | kill_pid_info(info->notify.sigev_signo, |
541 | &sig_i, info->notify_owner); | |
1da177e4 LT |
542 | break; |
543 | case SIGEV_THREAD: | |
544 | set_cookie(info->notify_cookie, NOTIFY_WOKENUP); | |
7ee015e0 | 545 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 LT |
546 | break; |
547 | } | |
548 | /* after notification unregisters process */ | |
a03fcb73 CLG |
549 | put_pid(info->notify_owner); |
550 | info->notify_owner = NULL; | |
1da177e4 LT |
551 | } |
552 | wake_up(&info->wait_q); | |
553 | } | |
554 | ||
c32c8af4 | 555 | static long prepare_timeout(struct timespec *p) |
1da177e4 | 556 | { |
c32c8af4 | 557 | struct timespec nowts; |
1da177e4 LT |
558 | long timeout; |
559 | ||
c32c8af4 AV |
560 | if (p) { |
561 | if (unlikely(p->tv_nsec < 0 || p->tv_sec < 0 | |
562 | || p->tv_nsec >= NSEC_PER_SEC)) | |
1da177e4 LT |
563 | return -EINVAL; |
564 | nowts = CURRENT_TIME; | |
565 | /* first subtract as jiffies can't be too big */ | |
c32c8af4 AV |
566 | p->tv_sec -= nowts.tv_sec; |
567 | if (p->tv_nsec < nowts.tv_nsec) { | |
568 | p->tv_nsec += NSEC_PER_SEC; | |
569 | p->tv_sec--; | |
1da177e4 | 570 | } |
c32c8af4 AV |
571 | p->tv_nsec -= nowts.tv_nsec; |
572 | if (p->tv_sec < 0) | |
1da177e4 LT |
573 | return 0; |
574 | ||
c32c8af4 | 575 | timeout = timespec_to_jiffies(p) + 1; |
1da177e4 LT |
576 | } else |
577 | return MAX_SCHEDULE_TIMEOUT; | |
578 | ||
579 | return timeout; | |
580 | } | |
581 | ||
582 | static void remove_notification(struct mqueue_inode_info *info) | |
583 | { | |
a03fcb73 | 584 | if (info->notify_owner != NULL && |
1da177e4 LT |
585 | info->notify.sigev_notify == SIGEV_THREAD) { |
586 | set_cookie(info->notify_cookie, NOTIFY_REMOVED); | |
7ee015e0 | 587 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 | 588 | } |
a03fcb73 CLG |
589 | put_pid(info->notify_owner); |
590 | info->notify_owner = NULL; | |
1da177e4 LT |
591 | } |
592 | ||
614b84cf | 593 | static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr) |
1da177e4 LT |
594 | { |
595 | if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0) | |
596 | return 0; | |
597 | if (capable(CAP_SYS_RESOURCE)) { | |
598 | if (attr->mq_maxmsg > HARD_MSGMAX) | |
599 | return 0; | |
600 | } else { | |
614b84cf SH |
601 | if (attr->mq_maxmsg > ipc_ns->mq_msg_max || |
602 | attr->mq_msgsize > ipc_ns->mq_msgsize_max) | |
1da177e4 LT |
603 | return 0; |
604 | } | |
605 | /* check for overflow */ | |
606 | if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg) | |
607 | return 0; | |
608 | if ((unsigned long)(attr->mq_maxmsg * attr->mq_msgsize) + | |
609 | (attr->mq_maxmsg * sizeof (struct msg_msg *)) < | |
610 | (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize)) | |
611 | return 0; | |
612 | return 1; | |
613 | } | |
614 | ||
615 | /* | |
616 | * Invoked when creating a new queue via sys_mq_open | |
617 | */ | |
614b84cf SH |
618 | static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir, |
619 | struct dentry *dentry, int oflag, mode_t mode, | |
620 | struct mq_attr *attr) | |
1da177e4 | 621 | { |
745ca247 | 622 | const struct cred *cred = current_cred(); |
4a3fd211 | 623 | struct file *result; |
1da177e4 LT |
624 | int ret; |
625 | ||
564f6993 | 626 | if (attr) { |
7c7dce92 | 627 | ret = -EINVAL; |
614b84cf | 628 | if (!mq_attr_ok(ipc_ns, attr)) |
7c7dce92 | 629 | goto out; |
1da177e4 | 630 | /* store for use during create */ |
564f6993 | 631 | dentry->d_fsdata = attr; |
1da177e4 LT |
632 | } |
633 | ||
ce3b0f8d | 634 | mode &= ~current_umask(); |
614b84cf | 635 | ret = mnt_want_write(ipc_ns->mq_mnt); |
4a3fd211 DH |
636 | if (ret) |
637 | goto out; | |
1da177e4 LT |
638 | ret = vfs_create(dir->d_inode, dentry, mode, NULL); |
639 | dentry->d_fsdata = NULL; | |
640 | if (ret) | |
4a3fd211 DH |
641 | goto out_drop_write; |
642 | ||
614b84cf | 643 | result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred); |
4a3fd211 DH |
644 | /* |
645 | * dentry_open() took a persistent mnt_want_write(), | |
646 | * so we can now drop this one. | |
647 | */ | |
614b84cf | 648 | mnt_drop_write(ipc_ns->mq_mnt); |
4a3fd211 DH |
649 | return result; |
650 | ||
651 | out_drop_write: | |
614b84cf | 652 | mnt_drop_write(ipc_ns->mq_mnt); |
7c7dce92 AV |
653 | out: |
654 | dput(dentry); | |
614b84cf | 655 | mntput(ipc_ns->mq_mnt); |
7c7dce92 | 656 | return ERR_PTR(ret); |
1da177e4 LT |
657 | } |
658 | ||
659 | /* Opens existing queue */ | |
614b84cf SH |
660 | static struct file *do_open(struct ipc_namespace *ipc_ns, |
661 | struct dentry *dentry, int oflag) | |
1da177e4 | 662 | { |
745ca247 DH |
663 | const struct cred *cred = current_cred(); |
664 | ||
665 | static const int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE, | |
666 | MAY_READ | MAY_WRITE }; | |
1da177e4 | 667 | |
7c7dce92 AV |
668 | if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) { |
669 | dput(dentry); | |
614b84cf | 670 | mntput(ipc_ns->mq_mnt); |
1da177e4 | 671 | return ERR_PTR(-EINVAL); |
7c7dce92 | 672 | } |
1da177e4 | 673 | |
f419a2e3 | 674 | if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) { |
7c7dce92 | 675 | dput(dentry); |
614b84cf | 676 | mntput(ipc_ns->mq_mnt); |
1da177e4 | 677 | return ERR_PTR(-EACCES); |
7c7dce92 | 678 | } |
1da177e4 | 679 | |
614b84cf | 680 | return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred); |
1da177e4 LT |
681 | } |
682 | ||
d5460c99 HC |
683 | SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode, |
684 | struct mq_attr __user *, u_attr) | |
1da177e4 LT |
685 | { |
686 | struct dentry *dentry; | |
687 | struct file *filp; | |
688 | char *name; | |
564f6993 | 689 | struct mq_attr attr; |
1da177e4 | 690 | int fd, error; |
7eafd7c7 | 691 | struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; |
1da177e4 | 692 | |
564f6993 AV |
693 | if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr))) |
694 | return -EFAULT; | |
695 | ||
696 | audit_mq_open(oflag, mode, u_attr ? &attr : NULL); | |
20ca73bc | 697 | |
1da177e4 LT |
698 | if (IS_ERR(name = getname(u_name))) |
699 | return PTR_ERR(name); | |
700 | ||
269f2134 | 701 | fd = get_unused_fd_flags(O_CLOEXEC); |
1da177e4 LT |
702 | if (fd < 0) |
703 | goto out_putname; | |
704 | ||
614b84cf SH |
705 | mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
706 | dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name)); | |
1da177e4 LT |
707 | if (IS_ERR(dentry)) { |
708 | error = PTR_ERR(dentry); | |
709 | goto out_err; | |
710 | } | |
614b84cf | 711 | mntget(ipc_ns->mq_mnt); |
1da177e4 LT |
712 | |
713 | if (oflag & O_CREAT) { | |
714 | if (dentry->d_inode) { /* entry already exists */ | |
5a190ae6 | 715 | audit_inode(name, dentry); |
7c7dce92 AV |
716 | error = -EEXIST; |
717 | if (oflag & O_EXCL) | |
718 | goto out; | |
614b84cf | 719 | filp = do_open(ipc_ns, dentry, oflag); |
1da177e4 | 720 | } else { |
614b84cf SH |
721 | filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root, |
722 | dentry, oflag, mode, | |
564f6993 | 723 | u_attr ? &attr : NULL); |
1da177e4 | 724 | } |
7c7dce92 AV |
725 | } else { |
726 | error = -ENOENT; | |
727 | if (!dentry->d_inode) | |
728 | goto out; | |
5a190ae6 | 729 | audit_inode(name, dentry); |
614b84cf | 730 | filp = do_open(ipc_ns, dentry, oflag); |
7c7dce92 | 731 | } |
1da177e4 LT |
732 | |
733 | if (IS_ERR(filp)) { | |
734 | error = PTR_ERR(filp); | |
735 | goto out_putfd; | |
736 | } | |
46690f37 | 737 | ima_counts_get(filp); |
1da177e4 | 738 | |
1da177e4 LT |
739 | fd_install(fd, filp); |
740 | goto out_upsem; | |
741 | ||
7c7dce92 AV |
742 | out: |
743 | dput(dentry); | |
614b84cf | 744 | mntput(ipc_ns->mq_mnt); |
7c7dce92 | 745 | out_putfd: |
1da177e4 LT |
746 | put_unused_fd(fd); |
747 | out_err: | |
748 | fd = error; | |
749 | out_upsem: | |
614b84cf | 750 | mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
751 | out_putname: |
752 | putname(name); | |
753 | return fd; | |
754 | } | |
755 | ||
d5460c99 | 756 | SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) |
1da177e4 LT |
757 | { |
758 | int err; | |
759 | char *name; | |
760 | struct dentry *dentry; | |
761 | struct inode *inode = NULL; | |
7eafd7c7 | 762 | struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; |
1da177e4 LT |
763 | |
764 | name = getname(u_name); | |
765 | if (IS_ERR(name)) | |
766 | return PTR_ERR(name); | |
767 | ||
614b84cf | 768 | mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex, |
7a434814 | 769 | I_MUTEX_PARENT); |
614b84cf | 770 | dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name)); |
1da177e4 LT |
771 | if (IS_ERR(dentry)) { |
772 | err = PTR_ERR(dentry); | |
773 | goto out_unlock; | |
774 | } | |
775 | ||
776 | if (!dentry->d_inode) { | |
777 | err = -ENOENT; | |
778 | goto out_err; | |
779 | } | |
780 | ||
781 | inode = dentry->d_inode; | |
782 | if (inode) | |
783 | atomic_inc(&inode->i_count); | |
614b84cf | 784 | err = mnt_want_write(ipc_ns->mq_mnt); |
0622753b DH |
785 | if (err) |
786 | goto out_err; | |
1da177e4 | 787 | err = vfs_unlink(dentry->d_parent->d_inode, dentry); |
614b84cf | 788 | mnt_drop_write(ipc_ns->mq_mnt); |
1da177e4 LT |
789 | out_err: |
790 | dput(dentry); | |
791 | ||
792 | out_unlock: | |
614b84cf | 793 | mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
794 | putname(name); |
795 | if (inode) | |
796 | iput(inode); | |
797 | ||
798 | return err; | |
799 | } | |
800 | ||
801 | /* Pipelined send and receive functions. | |
802 | * | |
803 | * If a receiver finds no waiting message, then it registers itself in the | |
804 | * list of waiting receivers. A sender checks that list before adding the new | |
805 | * message into the message array. If there is a waiting receiver, then it | |
806 | * bypasses the message array and directly hands the message over to the | |
807 | * receiver. | |
808 | * The receiver accepts the message and returns without grabbing the queue | |
809 | * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers | |
810 | * are necessary. The same algorithm is used for sysv semaphores, see | |
7b7a317c | 811 | * ipc/sem.c for more details. |
1da177e4 LT |
812 | * |
813 | * The same algorithm is used for senders. | |
814 | */ | |
815 | ||
816 | /* pipelined_send() - send a message directly to the task waiting in | |
817 | * sys_mq_timedreceive() (without inserting message into a queue). | |
818 | */ | |
819 | static inline void pipelined_send(struct mqueue_inode_info *info, | |
820 | struct msg_msg *message, | |
821 | struct ext_wait_queue *receiver) | |
822 | { | |
823 | receiver->msg = message; | |
824 | list_del(&receiver->list); | |
825 | receiver->state = STATE_PENDING; | |
826 | wake_up_process(receiver->task); | |
d59dd462 | 827 | smp_wmb(); |
1da177e4 LT |
828 | receiver->state = STATE_READY; |
829 | } | |
830 | ||
831 | /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() | |
832 | * gets its message and put to the queue (we have one free place for sure). */ | |
833 | static inline void pipelined_receive(struct mqueue_inode_info *info) | |
834 | { | |
835 | struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND); | |
836 | ||
837 | if (!sender) { | |
838 | /* for poll */ | |
839 | wake_up_interruptible(&info->wait_q); | |
840 | return; | |
841 | } | |
842 | msg_insert(sender->msg, info); | |
843 | list_del(&sender->list); | |
844 | sender->state = STATE_PENDING; | |
845 | wake_up_process(sender->task); | |
d59dd462 | 846 | smp_wmb(); |
1da177e4 LT |
847 | sender->state = STATE_READY; |
848 | } | |
849 | ||
c4ea37c2 HC |
850 | SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr, |
851 | size_t, msg_len, unsigned int, msg_prio, | |
852 | const struct timespec __user *, u_abs_timeout) | |
1da177e4 LT |
853 | { |
854 | struct file *filp; | |
855 | struct inode *inode; | |
856 | struct ext_wait_queue wait; | |
857 | struct ext_wait_queue *receiver; | |
858 | struct msg_msg *msg_ptr; | |
859 | struct mqueue_inode_info *info; | |
c32c8af4 | 860 | struct timespec ts, *p = NULL; |
1da177e4 LT |
861 | long timeout; |
862 | int ret; | |
863 | ||
c32c8af4 AV |
864 | if (u_abs_timeout) { |
865 | if (copy_from_user(&ts, u_abs_timeout, | |
866 | sizeof(struct timespec))) | |
867 | return -EFAULT; | |
868 | p = &ts; | |
869 | } | |
20ca73bc | 870 | |
1da177e4 LT |
871 | if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX)) |
872 | return -EINVAL; | |
873 | ||
c32c8af4 AV |
874 | audit_mq_sendrecv(mqdes, msg_len, msg_prio, p); |
875 | timeout = prepare_timeout(p); | |
1da177e4 LT |
876 | |
877 | ret = -EBADF; | |
878 | filp = fget(mqdes); | |
879 | if (unlikely(!filp)) | |
880 | goto out; | |
881 | ||
6d63079a | 882 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
883 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
884 | goto out_fput; | |
885 | info = MQUEUE_I(inode); | |
5a190ae6 | 886 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
887 | |
888 | if (unlikely(!(filp->f_mode & FMODE_WRITE))) | |
889 | goto out_fput; | |
890 | ||
891 | if (unlikely(msg_len > info->attr.mq_msgsize)) { | |
892 | ret = -EMSGSIZE; | |
893 | goto out_fput; | |
894 | } | |
895 | ||
896 | /* First try to allocate memory, before doing anything with | |
897 | * existing queues. */ | |
898 | msg_ptr = load_msg(u_msg_ptr, msg_len); | |
899 | if (IS_ERR(msg_ptr)) { | |
900 | ret = PTR_ERR(msg_ptr); | |
901 | goto out_fput; | |
902 | } | |
903 | msg_ptr->m_ts = msg_len; | |
904 | msg_ptr->m_type = msg_prio; | |
905 | ||
906 | spin_lock(&info->lock); | |
907 | ||
908 | if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) { | |
909 | if (filp->f_flags & O_NONBLOCK) { | |
910 | spin_unlock(&info->lock); | |
911 | ret = -EAGAIN; | |
912 | } else if (unlikely(timeout < 0)) { | |
913 | spin_unlock(&info->lock); | |
914 | ret = timeout; | |
915 | } else { | |
916 | wait.task = current; | |
917 | wait.msg = (void *) msg_ptr; | |
918 | wait.state = STATE_NONE; | |
919 | ret = wq_sleep(info, SEND, timeout, &wait); | |
920 | } | |
921 | if (ret < 0) | |
922 | free_msg(msg_ptr); | |
923 | } else { | |
924 | receiver = wq_get_first_waiter(info, RECV); | |
925 | if (receiver) { | |
926 | pipelined_send(info, msg_ptr, receiver); | |
927 | } else { | |
928 | /* adds message to the queue */ | |
929 | msg_insert(msg_ptr, info); | |
930 | __do_notify(info); | |
931 | } | |
932 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
933 | CURRENT_TIME; | |
934 | spin_unlock(&info->lock); | |
935 | ret = 0; | |
936 | } | |
937 | out_fput: | |
938 | fput(filp); | |
939 | out: | |
940 | return ret; | |
941 | } | |
942 | ||
c4ea37c2 HC |
943 | SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr, |
944 | size_t, msg_len, unsigned int __user *, u_msg_prio, | |
945 | const struct timespec __user *, u_abs_timeout) | |
1da177e4 LT |
946 | { |
947 | long timeout; | |
948 | ssize_t ret; | |
949 | struct msg_msg *msg_ptr; | |
950 | struct file *filp; | |
951 | struct inode *inode; | |
952 | struct mqueue_inode_info *info; | |
953 | struct ext_wait_queue wait; | |
c32c8af4 | 954 | struct timespec ts, *p = NULL; |
1da177e4 | 955 | |
c32c8af4 AV |
956 | if (u_abs_timeout) { |
957 | if (copy_from_user(&ts, u_abs_timeout, | |
958 | sizeof(struct timespec))) | |
959 | return -EFAULT; | |
960 | p = &ts; | |
961 | } | |
20ca73bc | 962 | |
c32c8af4 AV |
963 | audit_mq_sendrecv(mqdes, msg_len, 0, p); |
964 | timeout = prepare_timeout(p); | |
1da177e4 LT |
965 | |
966 | ret = -EBADF; | |
967 | filp = fget(mqdes); | |
968 | if (unlikely(!filp)) | |
969 | goto out; | |
970 | ||
6d63079a | 971 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
972 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
973 | goto out_fput; | |
974 | info = MQUEUE_I(inode); | |
5a190ae6 | 975 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
976 | |
977 | if (unlikely(!(filp->f_mode & FMODE_READ))) | |
978 | goto out_fput; | |
979 | ||
980 | /* checks if buffer is big enough */ | |
981 | if (unlikely(msg_len < info->attr.mq_msgsize)) { | |
982 | ret = -EMSGSIZE; | |
983 | goto out_fput; | |
984 | } | |
985 | ||
986 | spin_lock(&info->lock); | |
987 | if (info->attr.mq_curmsgs == 0) { | |
988 | if (filp->f_flags & O_NONBLOCK) { | |
989 | spin_unlock(&info->lock); | |
990 | ret = -EAGAIN; | |
991 | msg_ptr = NULL; | |
992 | } else if (unlikely(timeout < 0)) { | |
993 | spin_unlock(&info->lock); | |
994 | ret = timeout; | |
995 | msg_ptr = NULL; | |
996 | } else { | |
997 | wait.task = current; | |
998 | wait.state = STATE_NONE; | |
999 | ret = wq_sleep(info, RECV, timeout, &wait); | |
1000 | msg_ptr = wait.msg; | |
1001 | } | |
1002 | } else { | |
1003 | msg_ptr = msg_get(info); | |
1004 | ||
1005 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
1006 | CURRENT_TIME; | |
1007 | ||
1008 | /* There is now free space in queue. */ | |
1009 | pipelined_receive(info); | |
1010 | spin_unlock(&info->lock); | |
1011 | ret = 0; | |
1012 | } | |
1013 | if (ret == 0) { | |
1014 | ret = msg_ptr->m_ts; | |
1015 | ||
1016 | if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) || | |
1017 | store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) { | |
1018 | ret = -EFAULT; | |
1019 | } | |
1020 | free_msg(msg_ptr); | |
1021 | } | |
1022 | out_fput: | |
1023 | fput(filp); | |
1024 | out: | |
1025 | return ret; | |
1026 | } | |
1027 | ||
1028 | /* | |
1029 | * Notes: the case when user wants us to deregister (with NULL as pointer) | |
1030 | * and he isn't currently owner of notification, will be silently discarded. | |
1031 | * It isn't explicitly defined in the POSIX. | |
1032 | */ | |
c4ea37c2 HC |
1033 | SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes, |
1034 | const struct sigevent __user *, u_notification) | |
1da177e4 LT |
1035 | { |
1036 | int ret; | |
1037 | struct file *filp; | |
1038 | struct sock *sock; | |
1039 | struct inode *inode; | |
1040 | struct sigevent notification; | |
1041 | struct mqueue_inode_info *info; | |
1042 | struct sk_buff *nc; | |
1043 | ||
20114f71 | 1044 | if (u_notification) { |
1da177e4 LT |
1045 | if (copy_from_user(¬ification, u_notification, |
1046 | sizeof(struct sigevent))) | |
1047 | return -EFAULT; | |
20114f71 AV |
1048 | } |
1049 | ||
1050 | audit_mq_notify(mqdes, u_notification ? ¬ification : NULL); | |
1da177e4 | 1051 | |
20114f71 AV |
1052 | nc = NULL; |
1053 | sock = NULL; | |
1054 | if (u_notification != NULL) { | |
1da177e4 LT |
1055 | if (unlikely(notification.sigev_notify != SIGEV_NONE && |
1056 | notification.sigev_notify != SIGEV_SIGNAL && | |
1057 | notification.sigev_notify != SIGEV_THREAD)) | |
1058 | return -EINVAL; | |
1059 | if (notification.sigev_notify == SIGEV_SIGNAL && | |
7ed20e1a | 1060 | !valid_signal(notification.sigev_signo)) { |
1da177e4 LT |
1061 | return -EINVAL; |
1062 | } | |
1063 | if (notification.sigev_notify == SIGEV_THREAD) { | |
c3d8d1e3 PM |
1064 | long timeo; |
1065 | ||
1da177e4 LT |
1066 | /* create the notify skb */ |
1067 | nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL); | |
1068 | ret = -ENOMEM; | |
1069 | if (!nc) | |
1070 | goto out; | |
1071 | ret = -EFAULT; | |
1072 | if (copy_from_user(nc->data, | |
1073 | notification.sigev_value.sival_ptr, | |
1074 | NOTIFY_COOKIE_LEN)) { | |
1075 | goto out; | |
1076 | } | |
1077 | ||
1078 | /* TODO: add a header? */ | |
1079 | skb_put(nc, NOTIFY_COOKIE_LEN); | |
1080 | /* and attach it to the socket */ | |
1081 | retry: | |
1082 | filp = fget(notification.sigev_signo); | |
1083 | ret = -EBADF; | |
1084 | if (!filp) | |
1085 | goto out; | |
1086 | sock = netlink_getsockbyfilp(filp); | |
1087 | fput(filp); | |
1088 | if (IS_ERR(sock)) { | |
1089 | ret = PTR_ERR(sock); | |
1090 | sock = NULL; | |
1091 | goto out; | |
1092 | } | |
1093 | ||
c3d8d1e3 | 1094 | timeo = MAX_SCHEDULE_TIMEOUT; |
9457afee | 1095 | ret = netlink_attachskb(sock, nc, &timeo, NULL); |
1da177e4 LT |
1096 | if (ret == 1) |
1097 | goto retry; | |
1098 | if (ret) { | |
1099 | sock = NULL; | |
1100 | nc = NULL; | |
1101 | goto out; | |
1102 | } | |
1103 | } | |
1104 | } | |
1105 | ||
1106 | ret = -EBADF; | |
1107 | filp = fget(mqdes); | |
1108 | if (!filp) | |
1109 | goto out; | |
1110 | ||
6d63079a | 1111 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1112 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1113 | goto out_fput; | |
1114 | info = MQUEUE_I(inode); | |
1115 | ||
1116 | ret = 0; | |
1117 | spin_lock(&info->lock); | |
1118 | if (u_notification == NULL) { | |
a03fcb73 | 1119 | if (info->notify_owner == task_tgid(current)) { |
1da177e4 LT |
1120 | remove_notification(info); |
1121 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1122 | } | |
a03fcb73 | 1123 | } else if (info->notify_owner != NULL) { |
1da177e4 LT |
1124 | ret = -EBUSY; |
1125 | } else { | |
1126 | switch (notification.sigev_notify) { | |
1127 | case SIGEV_NONE: | |
1128 | info->notify.sigev_notify = SIGEV_NONE; | |
1129 | break; | |
1130 | case SIGEV_THREAD: | |
1131 | info->notify_sock = sock; | |
1132 | info->notify_cookie = nc; | |
1133 | sock = NULL; | |
1134 | nc = NULL; | |
1135 | info->notify.sigev_notify = SIGEV_THREAD; | |
1136 | break; | |
1137 | case SIGEV_SIGNAL: | |
1138 | info->notify.sigev_signo = notification.sigev_signo; | |
1139 | info->notify.sigev_value = notification.sigev_value; | |
1140 | info->notify.sigev_notify = SIGEV_SIGNAL; | |
1141 | break; | |
1142 | } | |
a03fcb73 CLG |
1143 | |
1144 | info->notify_owner = get_pid(task_tgid(current)); | |
1da177e4 LT |
1145 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1146 | } | |
1147 | spin_unlock(&info->lock); | |
1148 | out_fput: | |
1149 | fput(filp); | |
1150 | out: | |
1151 | if (sock) { | |
1152 | netlink_detachskb(sock, nc); | |
1153 | } else if (nc) { | |
1154 | dev_kfree_skb(nc); | |
1155 | } | |
1156 | return ret; | |
1157 | } | |
1158 | ||
c4ea37c2 HC |
1159 | SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes, |
1160 | const struct mq_attr __user *, u_mqstat, | |
1161 | struct mq_attr __user *, u_omqstat) | |
1da177e4 LT |
1162 | { |
1163 | int ret; | |
1164 | struct mq_attr mqstat, omqstat; | |
1165 | struct file *filp; | |
1166 | struct inode *inode; | |
1167 | struct mqueue_inode_info *info; | |
1168 | ||
1169 | if (u_mqstat != NULL) { | |
1170 | if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr))) | |
1171 | return -EFAULT; | |
1172 | if (mqstat.mq_flags & (~O_NONBLOCK)) | |
1173 | return -EINVAL; | |
1174 | } | |
1175 | ||
1176 | ret = -EBADF; | |
1177 | filp = fget(mqdes); | |
1178 | if (!filp) | |
1179 | goto out; | |
1180 | ||
6d63079a | 1181 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1182 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1183 | goto out_fput; | |
1184 | info = MQUEUE_I(inode); | |
1185 | ||
1186 | spin_lock(&info->lock); | |
1187 | ||
1188 | omqstat = info->attr; | |
1189 | omqstat.mq_flags = filp->f_flags & O_NONBLOCK; | |
1190 | if (u_mqstat) { | |
7392906e | 1191 | audit_mq_getsetattr(mqdes, &mqstat); |
db1dd4d3 | 1192 | spin_lock(&filp->f_lock); |
1da177e4 LT |
1193 | if (mqstat.mq_flags & O_NONBLOCK) |
1194 | filp->f_flags |= O_NONBLOCK; | |
1195 | else | |
1196 | filp->f_flags &= ~O_NONBLOCK; | |
db1dd4d3 | 1197 | spin_unlock(&filp->f_lock); |
1da177e4 LT |
1198 | |
1199 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1200 | } | |
1201 | ||
1202 | spin_unlock(&info->lock); | |
1203 | ||
1204 | ret = 0; | |
1205 | if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat, | |
1206 | sizeof(struct mq_attr))) | |
1207 | ret = -EFAULT; | |
1208 | ||
1209 | out_fput: | |
1210 | fput(filp); | |
1211 | out: | |
1212 | return ret; | |
1213 | } | |
1214 | ||
92e1d5be | 1215 | static const struct inode_operations mqueue_dir_inode_operations = { |
1da177e4 LT |
1216 | .lookup = simple_lookup, |
1217 | .create = mqueue_create, | |
1218 | .unlink = mqueue_unlink, | |
1219 | }; | |
1220 | ||
9a32144e | 1221 | static const struct file_operations mqueue_file_operations = { |
1da177e4 LT |
1222 | .flush = mqueue_flush_file, |
1223 | .poll = mqueue_poll_file, | |
1224 | .read = mqueue_read_file, | |
1225 | }; | |
1226 | ||
1227 | static struct super_operations mqueue_super_ops = { | |
1228 | .alloc_inode = mqueue_alloc_inode, | |
1229 | .destroy_inode = mqueue_destroy_inode, | |
1230 | .statfs = simple_statfs, | |
1231 | .delete_inode = mqueue_delete_inode, | |
1232 | .drop_inode = generic_delete_inode, | |
1233 | }; | |
1234 | ||
1235 | static struct file_system_type mqueue_fs_type = { | |
1236 | .name = "mqueue", | |
1237 | .get_sb = mqueue_get_sb, | |
1238 | .kill_sb = kill_litter_super, | |
1239 | }; | |
1240 | ||
7eafd7c7 SH |
1241 | int mq_init_ns(struct ipc_namespace *ns) |
1242 | { | |
1243 | ns->mq_queues_count = 0; | |
1244 | ns->mq_queues_max = DFLT_QUEUESMAX; | |
1245 | ns->mq_msg_max = DFLT_MSGMAX; | |
1246 | ns->mq_msgsize_max = DFLT_MSGSIZEMAX; | |
1247 | ||
1248 | ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns); | |
1249 | if (IS_ERR(ns->mq_mnt)) { | |
1250 | int err = PTR_ERR(ns->mq_mnt); | |
1251 | ns->mq_mnt = NULL; | |
1252 | return err; | |
1253 | } | |
1254 | return 0; | |
1255 | } | |
1256 | ||
1257 | void mq_clear_sbinfo(struct ipc_namespace *ns) | |
1258 | { | |
1259 | ns->mq_mnt->mnt_sb->s_fs_info = NULL; | |
1260 | } | |
1261 | ||
1262 | void mq_put_mnt(struct ipc_namespace *ns) | |
1263 | { | |
1264 | mntput(ns->mq_mnt); | |
1265 | } | |
1266 | ||
1da177e4 LT |
1267 | static int __init init_mqueue_fs(void) |
1268 | { | |
1269 | int error; | |
1270 | ||
1271 | mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache", | |
1272 | sizeof(struct mqueue_inode_info), 0, | |
20c2df83 | 1273 | SLAB_HWCACHE_ALIGN, init_once); |
1da177e4 LT |
1274 | if (mqueue_inode_cachep == NULL) |
1275 | return -ENOMEM; | |
1276 | ||
1277 | /* ignore failues - they are not fatal */ | |
bdc8e5f8 | 1278 | mq_sysctl_table = mq_register_sysctl_table(); |
1da177e4 LT |
1279 | |
1280 | error = register_filesystem(&mqueue_fs_type); | |
1281 | if (error) | |
1282 | goto out_sysctl; | |
1283 | ||
7eafd7c7 SH |
1284 | spin_lock_init(&mq_lock); |
1285 | ||
1286 | init_ipc_ns.mq_mnt = kern_mount_data(&mqueue_fs_type, &init_ipc_ns); | |
614b84cf SH |
1287 | if (IS_ERR(init_ipc_ns.mq_mnt)) { |
1288 | error = PTR_ERR(init_ipc_ns.mq_mnt); | |
1da177e4 LT |
1289 | goto out_filesystem; |
1290 | } | |
1291 | ||
1da177e4 LT |
1292 | return 0; |
1293 | ||
1294 | out_filesystem: | |
1295 | unregister_filesystem(&mqueue_fs_type); | |
1296 | out_sysctl: | |
1297 | if (mq_sysctl_table) | |
1298 | unregister_sysctl_table(mq_sysctl_table); | |
1a1d92c1 | 1299 | kmem_cache_destroy(mqueue_inode_cachep); |
1da177e4 LT |
1300 | return error; |
1301 | } | |
1302 | ||
1303 | __initcall(init_mqueue_fs); |