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> |
5f921ae9 | 35 | |
1da177e4 LT |
36 | #include <net/sock.h> |
37 | #include "util.h" | |
38 | ||
39 | #define MQUEUE_MAGIC 0x19800202 | |
40 | #define DIRENT_SIZE 20 | |
41 | #define FILENT_SIZE 80 | |
42 | ||
43 | #define SEND 0 | |
44 | #define RECV 1 | |
45 | ||
46 | #define STATE_NONE 0 | |
47 | #define STATE_PENDING 1 | |
48 | #define STATE_READY 2 | |
49 | ||
1da177e4 LT |
50 | struct ext_wait_queue { /* queue of sleeping tasks */ |
51 | struct task_struct *task; | |
52 | struct list_head list; | |
53 | struct msg_msg *msg; /* ptr of loaded message */ | |
54 | int state; /* one of STATE_* values */ | |
55 | }; | |
56 | ||
57 | struct mqueue_inode_info { | |
58 | spinlock_t lock; | |
59 | struct inode vfs_inode; | |
60 | wait_queue_head_t wait_q; | |
61 | ||
62 | struct msg_msg **messages; | |
63 | struct mq_attr attr; | |
64 | ||
65 | struct sigevent notify; | |
a03fcb73 | 66 | struct pid* notify_owner; |
338cec32 | 67 | struct user_struct *user; /* user who created, for accounting */ |
1da177e4 LT |
68 | struct sock *notify_sock; |
69 | struct sk_buff *notify_cookie; | |
70 | ||
71 | /* for tasks waiting for free space and messages, respectively */ | |
72 | struct ext_wait_queue e_wait_q[2]; | |
73 | ||
74 | unsigned long qsize; /* size of queue in memory (sum of all msgs) */ | |
75 | }; | |
76 | ||
92e1d5be | 77 | static const struct inode_operations mqueue_dir_inode_operations; |
9a32144e | 78 | static const struct file_operations mqueue_file_operations; |
b87221de | 79 | static const struct super_operations mqueue_super_ops; |
1da177e4 LT |
80 | static void remove_notification(struct mqueue_inode_info *info); |
81 | ||
e18b890b | 82 | static struct kmem_cache *mqueue_inode_cachep; |
1da177e4 LT |
83 | |
84 | static struct ctl_table_header * mq_sysctl_table; | |
85 | ||
86 | static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode) | |
87 | { | |
88 | return container_of(inode, struct mqueue_inode_info, vfs_inode); | |
89 | } | |
90 | ||
7eafd7c7 SH |
91 | /* |
92 | * This routine should be called with the mq_lock held. | |
93 | */ | |
94 | static inline struct ipc_namespace *__get_ns_from_inode(struct inode *inode) | |
614b84cf | 95 | { |
7eafd7c7 | 96 | return get_ipc_ns(inode->i_sb->s_fs_info); |
614b84cf SH |
97 | } |
98 | ||
7eafd7c7 | 99 | static struct ipc_namespace *get_ns_from_inode(struct inode *inode) |
614b84cf | 100 | { |
7eafd7c7 SH |
101 | struct ipc_namespace *ns; |
102 | ||
103 | spin_lock(&mq_lock); | |
104 | ns = __get_ns_from_inode(inode); | |
105 | spin_unlock(&mq_lock); | |
106 | return ns; | |
614b84cf SH |
107 | } |
108 | ||
7eafd7c7 SH |
109 | static struct inode *mqueue_get_inode(struct super_block *sb, |
110 | struct ipc_namespace *ipc_ns, int mode, | |
111 | struct mq_attr *attr) | |
1da177e4 | 112 | { |
86a264ab | 113 | struct user_struct *u = current_user(); |
1da177e4 LT |
114 | struct inode *inode; |
115 | ||
116 | inode = new_inode(sb); | |
117 | if (inode) { | |
118 | inode->i_mode = mode; | |
414c0708 DH |
119 | inode->i_uid = current_fsuid(); |
120 | inode->i_gid = current_fsgid(); | |
1da177e4 LT |
121 | inode->i_mtime = inode->i_ctime = inode->i_atime = |
122 | CURRENT_TIME; | |
123 | ||
124 | if (S_ISREG(mode)) { | |
125 | struct mqueue_inode_info *info; | |
126 | struct task_struct *p = current; | |
1da177e4 LT |
127 | unsigned long mq_bytes, mq_msg_tblsz; |
128 | ||
129 | inode->i_fop = &mqueue_file_operations; | |
130 | inode->i_size = FILENT_SIZE; | |
131 | /* mqueue specific info */ | |
132 | info = MQUEUE_I(inode); | |
133 | spin_lock_init(&info->lock); | |
134 | init_waitqueue_head(&info->wait_q); | |
135 | INIT_LIST_HEAD(&info->e_wait_q[0].list); | |
136 | INIT_LIST_HEAD(&info->e_wait_q[1].list); | |
a03fcb73 | 137 | info->notify_owner = NULL; |
1da177e4 LT |
138 | info->qsize = 0; |
139 | info->user = NULL; /* set when all is ok */ | |
140 | memset(&info->attr, 0, sizeof(info->attr)); | |
614b84cf SH |
141 | info->attr.mq_maxmsg = ipc_ns->mq_msg_max; |
142 | info->attr.mq_msgsize = ipc_ns->mq_msgsize_max; | |
1da177e4 LT |
143 | if (attr) { |
144 | info->attr.mq_maxmsg = attr->mq_maxmsg; | |
145 | info->attr.mq_msgsize = attr->mq_msgsize; | |
146 | } | |
147 | mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *); | |
c8308b1c AGR |
148 | info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL); |
149 | if (!info->messages) | |
150 | goto out_inode; | |
151 | ||
1da177e4 LT |
152 | mq_bytes = (mq_msg_tblsz + |
153 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); | |
154 | ||
155 | spin_lock(&mq_lock); | |
156 | if (u->mq_bytes + mq_bytes < u->mq_bytes || | |
157 | u->mq_bytes + mq_bytes > | |
158 | p->signal->rlim[RLIMIT_MSGQUEUE].rlim_cur) { | |
159 | spin_unlock(&mq_lock); | |
c8308b1c | 160 | kfree(info->messages); |
1da177e4 LT |
161 | goto out_inode; |
162 | } | |
163 | u->mq_bytes += mq_bytes; | |
164 | spin_unlock(&mq_lock); | |
165 | ||
1da177e4 LT |
166 | /* all is ok */ |
167 | info->user = get_uid(u); | |
168 | } else if (S_ISDIR(mode)) { | |
d8c76e6f | 169 | inc_nlink(inode); |
1da177e4 LT |
170 | /* Some things misbehave if size == 0 on a directory */ |
171 | inode->i_size = 2 * DIRENT_SIZE; | |
172 | inode->i_op = &mqueue_dir_inode_operations; | |
173 | inode->i_fop = &simple_dir_operations; | |
174 | } | |
175 | } | |
176 | return inode; | |
177 | out_inode: | |
178 | make_bad_inode(inode); | |
179 | iput(inode); | |
180 | return NULL; | |
181 | } | |
182 | ||
183 | static int mqueue_fill_super(struct super_block *sb, void *data, int silent) | |
184 | { | |
185 | struct inode *inode; | |
7eafd7c7 SH |
186 | struct ipc_namespace *ns = data; |
187 | int error = 0; | |
1da177e4 LT |
188 | |
189 | sb->s_blocksize = PAGE_CACHE_SIZE; | |
190 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; | |
191 | sb->s_magic = MQUEUE_MAGIC; | |
192 | sb->s_op = &mqueue_super_ops; | |
193 | ||
7eafd7c7 SH |
194 | inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO, |
195 | NULL); | |
196 | if (!inode) { | |
197 | error = -ENOMEM; | |
198 | goto out; | |
199 | } | |
1da177e4 LT |
200 | |
201 | sb->s_root = d_alloc_root(inode); | |
202 | if (!sb->s_root) { | |
203 | iput(inode); | |
7eafd7c7 | 204 | error = -ENOMEM; |
1da177e4 LT |
205 | } |
206 | ||
7eafd7c7 SH |
207 | out: |
208 | return error; | |
1da177e4 LT |
209 | } |
210 | ||
454e2398 DH |
211 | static int mqueue_get_sb(struct file_system_type *fs_type, |
212 | int flags, const char *dev_name, | |
213 | void *data, struct vfsmount *mnt) | |
1da177e4 | 214 | { |
7eafd7c7 SH |
215 | if (!(flags & MS_KERNMOUNT)) |
216 | data = current->nsproxy->ipc_ns; | |
217 | return get_sb_ns(fs_type, flags, data, mqueue_fill_super, mnt); | |
1da177e4 LT |
218 | } |
219 | ||
51cc5068 | 220 | static void init_once(void *foo) |
1da177e4 LT |
221 | { |
222 | struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo; | |
223 | ||
a35afb83 | 224 | inode_init_once(&p->vfs_inode); |
1da177e4 LT |
225 | } |
226 | ||
227 | static struct inode *mqueue_alloc_inode(struct super_block *sb) | |
228 | { | |
229 | struct mqueue_inode_info *ei; | |
230 | ||
e94b1766 | 231 | ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL); |
1da177e4 LT |
232 | if (!ei) |
233 | return NULL; | |
234 | return &ei->vfs_inode; | |
235 | } | |
236 | ||
237 | static void mqueue_destroy_inode(struct inode *inode) | |
238 | { | |
239 | kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode)); | |
240 | } | |
241 | ||
242 | static void mqueue_delete_inode(struct inode *inode) | |
243 | { | |
244 | struct mqueue_inode_info *info; | |
245 | struct user_struct *user; | |
246 | unsigned long mq_bytes; | |
247 | int i; | |
7eafd7c7 | 248 | struct ipc_namespace *ipc_ns; |
1da177e4 LT |
249 | |
250 | if (S_ISDIR(inode->i_mode)) { | |
251 | clear_inode(inode); | |
252 | return; | |
253 | } | |
7eafd7c7 | 254 | ipc_ns = get_ns_from_inode(inode); |
1da177e4 LT |
255 | info = MQUEUE_I(inode); |
256 | spin_lock(&info->lock); | |
257 | for (i = 0; i < info->attr.mq_curmsgs; i++) | |
258 | free_msg(info->messages[i]); | |
259 | kfree(info->messages); | |
260 | spin_unlock(&info->lock); | |
261 | ||
262 | clear_inode(inode); | |
263 | ||
8834cf79 AGR |
264 | /* Total amount of bytes accounted for the mqueue */ |
265 | mq_bytes = info->attr.mq_maxmsg * (sizeof(struct msg_msg *) | |
266 | + info->attr.mq_msgsize); | |
1da177e4 LT |
267 | user = info->user; |
268 | if (user) { | |
269 | spin_lock(&mq_lock); | |
270 | user->mq_bytes -= mq_bytes; | |
7eafd7c7 SH |
271 | /* |
272 | * get_ns_from_inode() ensures that the | |
273 | * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns | |
274 | * to which we now hold a reference, or it is NULL. | |
275 | * We can't put it here under mq_lock, though. | |
276 | */ | |
277 | if (ipc_ns) | |
278 | ipc_ns->mq_queues_count--; | |
1da177e4 LT |
279 | spin_unlock(&mq_lock); |
280 | free_uid(user); | |
281 | } | |
7eafd7c7 SH |
282 | if (ipc_ns) |
283 | put_ipc_ns(ipc_ns); | |
1da177e4 LT |
284 | } |
285 | ||
286 | static int mqueue_create(struct inode *dir, struct dentry *dentry, | |
287 | int mode, struct nameidata *nd) | |
288 | { | |
289 | struct inode *inode; | |
290 | struct mq_attr *attr = dentry->d_fsdata; | |
291 | int error; | |
7eafd7c7 | 292 | struct ipc_namespace *ipc_ns; |
1da177e4 LT |
293 | |
294 | spin_lock(&mq_lock); | |
7eafd7c7 SH |
295 | ipc_ns = __get_ns_from_inode(dir); |
296 | if (!ipc_ns) { | |
297 | error = -EACCES; | |
298 | goto out_unlock; | |
299 | } | |
614b84cf SH |
300 | if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max && |
301 | !capable(CAP_SYS_RESOURCE)) { | |
1da177e4 | 302 | error = -ENOSPC; |
614b84cf | 303 | goto out_unlock; |
1da177e4 | 304 | } |
614b84cf | 305 | ipc_ns->mq_queues_count++; |
1da177e4 LT |
306 | spin_unlock(&mq_lock); |
307 | ||
7eafd7c7 | 308 | inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr); |
1da177e4 LT |
309 | if (!inode) { |
310 | error = -ENOMEM; | |
311 | spin_lock(&mq_lock); | |
614b84cf SH |
312 | ipc_ns->mq_queues_count--; |
313 | goto out_unlock; | |
1da177e4 LT |
314 | } |
315 | ||
7eafd7c7 | 316 | put_ipc_ns(ipc_ns); |
1da177e4 LT |
317 | dir->i_size += DIRENT_SIZE; |
318 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
319 | ||
320 | d_instantiate(dentry, inode); | |
321 | dget(dentry); | |
322 | return 0; | |
614b84cf | 323 | out_unlock: |
1da177e4 | 324 | spin_unlock(&mq_lock); |
7eafd7c7 SH |
325 | if (ipc_ns) |
326 | put_ipc_ns(ipc_ns); | |
1da177e4 LT |
327 | return error; |
328 | } | |
329 | ||
330 | static int mqueue_unlink(struct inode *dir, struct dentry *dentry) | |
331 | { | |
332 | struct inode *inode = dentry->d_inode; | |
333 | ||
334 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
335 | dir->i_size -= DIRENT_SIZE; | |
9a53c3a7 | 336 | drop_nlink(inode); |
1da177e4 LT |
337 | dput(dentry); |
338 | return 0; | |
339 | } | |
340 | ||
341 | /* | |
342 | * This is routine for system read from queue file. | |
343 | * To avoid mess with doing here some sort of mq_receive we allow | |
344 | * to read only queue size & notification info (the only values | |
345 | * that are interesting from user point of view and aren't accessible | |
346 | * through std routines) | |
347 | */ | |
348 | static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, | |
f1a43f93 | 349 | size_t count, loff_t *off) |
1da177e4 | 350 | { |
6d63079a | 351 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 | 352 | char buffer[FILENT_SIZE]; |
f1a43f93 | 353 | ssize_t ret; |
1da177e4 LT |
354 | |
355 | spin_lock(&info->lock); | |
356 | snprintf(buffer, sizeof(buffer), | |
357 | "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n", | |
358 | info->qsize, | |
359 | info->notify_owner ? info->notify.sigev_notify : 0, | |
360 | (info->notify_owner && | |
361 | info->notify.sigev_notify == SIGEV_SIGNAL) ? | |
362 | info->notify.sigev_signo : 0, | |
6c5f3e7b | 363 | pid_vnr(info->notify_owner)); |
1da177e4 LT |
364 | spin_unlock(&info->lock); |
365 | buffer[sizeof(buffer)-1] = '\0'; | |
1da177e4 | 366 | |
f1a43f93 AM |
367 | ret = simple_read_from_buffer(u_data, count, off, buffer, |
368 | strlen(buffer)); | |
369 | if (ret <= 0) | |
370 | return ret; | |
1da177e4 | 371 | |
6d63079a | 372 | filp->f_path.dentry->d_inode->i_atime = filp->f_path.dentry->d_inode->i_ctime = CURRENT_TIME; |
f1a43f93 | 373 | return ret; |
1da177e4 LT |
374 | } |
375 | ||
75e1fcc0 | 376 | static int mqueue_flush_file(struct file *filp, fl_owner_t id) |
1da177e4 | 377 | { |
6d63079a | 378 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
379 | |
380 | spin_lock(&info->lock); | |
a03fcb73 | 381 | if (task_tgid(current) == info->notify_owner) |
1da177e4 LT |
382 | remove_notification(info); |
383 | ||
384 | spin_unlock(&info->lock); | |
385 | return 0; | |
386 | } | |
387 | ||
388 | static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab) | |
389 | { | |
6d63079a | 390 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
391 | int retval = 0; |
392 | ||
393 | poll_wait(filp, &info->wait_q, poll_tab); | |
394 | ||
395 | spin_lock(&info->lock); | |
396 | if (info->attr.mq_curmsgs) | |
397 | retval = POLLIN | POLLRDNORM; | |
398 | ||
399 | if (info->attr.mq_curmsgs < info->attr.mq_maxmsg) | |
400 | retval |= POLLOUT | POLLWRNORM; | |
401 | spin_unlock(&info->lock); | |
402 | ||
403 | return retval; | |
404 | } | |
405 | ||
406 | /* Adds current to info->e_wait_q[sr] before element with smaller prio */ | |
407 | static void wq_add(struct mqueue_inode_info *info, int sr, | |
408 | struct ext_wait_queue *ewp) | |
409 | { | |
410 | struct ext_wait_queue *walk; | |
411 | ||
412 | ewp->task = current; | |
413 | ||
414 | list_for_each_entry(walk, &info->e_wait_q[sr].list, list) { | |
415 | if (walk->task->static_prio <= current->static_prio) { | |
416 | list_add_tail(&ewp->list, &walk->list); | |
417 | return; | |
418 | } | |
419 | } | |
420 | list_add_tail(&ewp->list, &info->e_wait_q[sr].list); | |
421 | } | |
422 | ||
423 | /* | |
424 | * Puts current task to sleep. Caller must hold queue lock. After return | |
425 | * lock isn't held. | |
426 | * sr: SEND or RECV | |
427 | */ | |
428 | static int wq_sleep(struct mqueue_inode_info *info, int sr, | |
429 | long timeout, struct ext_wait_queue *ewp) | |
430 | { | |
431 | int retval; | |
432 | signed long time; | |
433 | ||
434 | wq_add(info, sr, ewp); | |
435 | ||
436 | for (;;) { | |
437 | set_current_state(TASK_INTERRUPTIBLE); | |
438 | ||
439 | spin_unlock(&info->lock); | |
440 | time = schedule_timeout(timeout); | |
441 | ||
442 | while (ewp->state == STATE_PENDING) | |
443 | cpu_relax(); | |
444 | ||
445 | if (ewp->state == STATE_READY) { | |
446 | retval = 0; | |
447 | goto out; | |
448 | } | |
449 | spin_lock(&info->lock); | |
450 | if (ewp->state == STATE_READY) { | |
451 | retval = 0; | |
452 | goto out_unlock; | |
453 | } | |
454 | if (signal_pending(current)) { | |
455 | retval = -ERESTARTSYS; | |
456 | break; | |
457 | } | |
458 | if (time == 0) { | |
459 | retval = -ETIMEDOUT; | |
460 | break; | |
461 | } | |
462 | } | |
463 | list_del(&ewp->list); | |
464 | out_unlock: | |
465 | spin_unlock(&info->lock); | |
466 | out: | |
467 | return retval; | |
468 | } | |
469 | ||
470 | /* | |
471 | * Returns waiting task that should be serviced first or NULL if none exists | |
472 | */ | |
473 | static struct ext_wait_queue *wq_get_first_waiter( | |
474 | struct mqueue_inode_info *info, int sr) | |
475 | { | |
476 | struct list_head *ptr; | |
477 | ||
478 | ptr = info->e_wait_q[sr].list.prev; | |
479 | if (ptr == &info->e_wait_q[sr].list) | |
480 | return NULL; | |
481 | return list_entry(ptr, struct ext_wait_queue, list); | |
482 | } | |
483 | ||
484 | /* Auxiliary functions to manipulate messages' list */ | |
485 | static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info) | |
486 | { | |
487 | int k; | |
488 | ||
489 | k = info->attr.mq_curmsgs - 1; | |
490 | while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) { | |
491 | info->messages[k + 1] = info->messages[k]; | |
492 | k--; | |
493 | } | |
494 | info->attr.mq_curmsgs++; | |
495 | info->qsize += ptr->m_ts; | |
496 | info->messages[k + 1] = ptr; | |
497 | } | |
498 | ||
499 | static inline struct msg_msg *msg_get(struct mqueue_inode_info *info) | |
500 | { | |
501 | info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts; | |
502 | return info->messages[info->attr.mq_curmsgs]; | |
503 | } | |
504 | ||
505 | static inline void set_cookie(struct sk_buff *skb, char code) | |
506 | { | |
507 | ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code; | |
508 | } | |
509 | ||
510 | /* | |
511 | * The next function is only to split too long sys_mq_timedsend | |
512 | */ | |
513 | static void __do_notify(struct mqueue_inode_info *info) | |
514 | { | |
515 | /* notification | |
516 | * invoked when there is registered process and there isn't process | |
517 | * waiting synchronously for message AND state of queue changed from | |
518 | * empty to not empty. Here we are sure that no one is waiting | |
519 | * synchronously. */ | |
520 | if (info->notify_owner && | |
521 | info->attr.mq_curmsgs == 1) { | |
522 | struct siginfo sig_i; | |
523 | switch (info->notify.sigev_notify) { | |
524 | case SIGEV_NONE: | |
525 | break; | |
526 | case SIGEV_SIGNAL: | |
527 | /* sends signal */ | |
528 | ||
529 | sig_i.si_signo = info->notify.sigev_signo; | |
530 | sig_i.si_errno = 0; | |
531 | sig_i.si_code = SI_MESGQ; | |
532 | sig_i.si_value = info->notify.sigev_value; | |
a6684999 SB |
533 | sig_i.si_pid = task_tgid_nr_ns(current, |
534 | ns_of_pid(info->notify_owner)); | |
414c0708 | 535 | sig_i.si_uid = current_uid(); |
1da177e4 | 536 | |
a03fcb73 CLG |
537 | kill_pid_info(info->notify.sigev_signo, |
538 | &sig_i, info->notify_owner); | |
1da177e4 LT |
539 | break; |
540 | case SIGEV_THREAD: | |
541 | set_cookie(info->notify_cookie, NOTIFY_WOKENUP); | |
7ee015e0 | 542 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 LT |
543 | break; |
544 | } | |
545 | /* after notification unregisters process */ | |
a03fcb73 CLG |
546 | put_pid(info->notify_owner); |
547 | info->notify_owner = NULL; | |
1da177e4 LT |
548 | } |
549 | wake_up(&info->wait_q); | |
550 | } | |
551 | ||
c32c8af4 | 552 | static long prepare_timeout(struct timespec *p) |
1da177e4 | 553 | { |
c32c8af4 | 554 | struct timespec nowts; |
1da177e4 LT |
555 | long timeout; |
556 | ||
c32c8af4 AV |
557 | if (p) { |
558 | if (unlikely(p->tv_nsec < 0 || p->tv_sec < 0 | |
559 | || p->tv_nsec >= NSEC_PER_SEC)) | |
1da177e4 LT |
560 | return -EINVAL; |
561 | nowts = CURRENT_TIME; | |
562 | /* first subtract as jiffies can't be too big */ | |
c32c8af4 AV |
563 | p->tv_sec -= nowts.tv_sec; |
564 | if (p->tv_nsec < nowts.tv_nsec) { | |
565 | p->tv_nsec += NSEC_PER_SEC; | |
566 | p->tv_sec--; | |
1da177e4 | 567 | } |
c32c8af4 AV |
568 | p->tv_nsec -= nowts.tv_nsec; |
569 | if (p->tv_sec < 0) | |
1da177e4 LT |
570 | return 0; |
571 | ||
c32c8af4 | 572 | timeout = timespec_to_jiffies(p) + 1; |
1da177e4 LT |
573 | } else |
574 | return MAX_SCHEDULE_TIMEOUT; | |
575 | ||
576 | return timeout; | |
577 | } | |
578 | ||
579 | static void remove_notification(struct mqueue_inode_info *info) | |
580 | { | |
a03fcb73 | 581 | if (info->notify_owner != NULL && |
1da177e4 LT |
582 | info->notify.sigev_notify == SIGEV_THREAD) { |
583 | set_cookie(info->notify_cookie, NOTIFY_REMOVED); | |
7ee015e0 | 584 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 | 585 | } |
a03fcb73 CLG |
586 | put_pid(info->notify_owner); |
587 | info->notify_owner = NULL; | |
1da177e4 LT |
588 | } |
589 | ||
614b84cf | 590 | static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr) |
1da177e4 LT |
591 | { |
592 | if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0) | |
593 | return 0; | |
594 | if (capable(CAP_SYS_RESOURCE)) { | |
595 | if (attr->mq_maxmsg > HARD_MSGMAX) | |
596 | return 0; | |
597 | } else { | |
614b84cf SH |
598 | if (attr->mq_maxmsg > ipc_ns->mq_msg_max || |
599 | attr->mq_msgsize > ipc_ns->mq_msgsize_max) | |
1da177e4 LT |
600 | return 0; |
601 | } | |
602 | /* check for overflow */ | |
603 | if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg) | |
604 | return 0; | |
8834cf79 AGR |
605 | if ((unsigned long)(attr->mq_maxmsg * (attr->mq_msgsize |
606 | + sizeof (struct msg_msg *))) < | |
1da177e4 LT |
607 | (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize)) |
608 | return 0; | |
609 | return 1; | |
610 | } | |
611 | ||
612 | /* | |
613 | * Invoked when creating a new queue via sys_mq_open | |
614 | */ | |
614b84cf SH |
615 | static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir, |
616 | struct dentry *dentry, int oflag, mode_t mode, | |
617 | struct mq_attr *attr) | |
1da177e4 | 618 | { |
745ca247 | 619 | const struct cred *cred = current_cred(); |
4a3fd211 | 620 | struct file *result; |
1da177e4 LT |
621 | int ret; |
622 | ||
564f6993 | 623 | if (attr) { |
7c7dce92 | 624 | ret = -EINVAL; |
614b84cf | 625 | if (!mq_attr_ok(ipc_ns, attr)) |
7c7dce92 | 626 | goto out; |
1da177e4 | 627 | /* store for use during create */ |
564f6993 | 628 | dentry->d_fsdata = attr; |
1da177e4 LT |
629 | } |
630 | ||
ce3b0f8d | 631 | mode &= ~current_umask(); |
614b84cf | 632 | ret = mnt_want_write(ipc_ns->mq_mnt); |
4a3fd211 DH |
633 | if (ret) |
634 | goto out; | |
1da177e4 LT |
635 | ret = vfs_create(dir->d_inode, dentry, mode, NULL); |
636 | dentry->d_fsdata = NULL; | |
637 | if (ret) | |
4a3fd211 DH |
638 | goto out_drop_write; |
639 | ||
614b84cf | 640 | result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred); |
4a3fd211 DH |
641 | /* |
642 | * dentry_open() took a persistent mnt_want_write(), | |
643 | * so we can now drop this one. | |
644 | */ | |
614b84cf | 645 | mnt_drop_write(ipc_ns->mq_mnt); |
4a3fd211 DH |
646 | return result; |
647 | ||
648 | out_drop_write: | |
614b84cf | 649 | mnt_drop_write(ipc_ns->mq_mnt); |
7c7dce92 AV |
650 | out: |
651 | dput(dentry); | |
614b84cf | 652 | mntput(ipc_ns->mq_mnt); |
7c7dce92 | 653 | return ERR_PTR(ret); |
1da177e4 LT |
654 | } |
655 | ||
656 | /* Opens existing queue */ | |
614b84cf SH |
657 | static struct file *do_open(struct ipc_namespace *ipc_ns, |
658 | struct dentry *dentry, int oflag) | |
1da177e4 | 659 | { |
04db0dde | 660 | int ret; |
745ca247 DH |
661 | const struct cred *cred = current_cred(); |
662 | ||
663 | static const int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE, | |
664 | MAY_READ | MAY_WRITE }; | |
1da177e4 | 665 | |
7c7dce92 | 666 | if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) { |
04db0dde AGR |
667 | ret = -EINVAL; |
668 | goto err; | |
7c7dce92 | 669 | } |
1da177e4 | 670 | |
f419a2e3 | 671 | if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) { |
04db0dde AGR |
672 | ret = -EACCES; |
673 | goto err; | |
7c7dce92 | 674 | } |
1da177e4 | 675 | |
614b84cf | 676 | return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred); |
04db0dde AGR |
677 | |
678 | err: | |
679 | dput(dentry); | |
680 | mntput(ipc_ns->mq_mnt); | |
681 | return ERR_PTR(ret); | |
1da177e4 LT |
682 | } |
683 | ||
d5460c99 HC |
684 | SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, mode_t, mode, |
685 | struct mq_attr __user *, u_attr) | |
1da177e4 LT |
686 | { |
687 | struct dentry *dentry; | |
688 | struct file *filp; | |
689 | char *name; | |
564f6993 | 690 | struct mq_attr attr; |
1da177e4 | 691 | int fd, error; |
7eafd7c7 | 692 | struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; |
1da177e4 | 693 | |
564f6993 AV |
694 | if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr))) |
695 | return -EFAULT; | |
696 | ||
697 | audit_mq_open(oflag, mode, u_attr ? &attr : NULL); | |
20ca73bc | 698 | |
1da177e4 LT |
699 | if (IS_ERR(name = getname(u_name))) |
700 | return PTR_ERR(name); | |
701 | ||
269f2134 | 702 | fd = get_unused_fd_flags(O_CLOEXEC); |
1da177e4 LT |
703 | if (fd < 0) |
704 | goto out_putname; | |
705 | ||
614b84cf SH |
706 | mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
707 | dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name)); | |
1da177e4 LT |
708 | if (IS_ERR(dentry)) { |
709 | error = PTR_ERR(dentry); | |
4294a8ee | 710 | goto out_putfd; |
1da177e4 | 711 | } |
614b84cf | 712 | mntget(ipc_ns->mq_mnt); |
1da177e4 LT |
713 | |
714 | if (oflag & O_CREAT) { | |
715 | if (dentry->d_inode) { /* entry already exists */ | |
5a190ae6 | 716 | audit_inode(name, dentry); |
7c7dce92 AV |
717 | error = -EEXIST; |
718 | if (oflag & O_EXCL) | |
719 | goto out; | |
614b84cf | 720 | filp = do_open(ipc_ns, dentry, oflag); |
1da177e4 | 721 | } else { |
614b84cf SH |
722 | filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root, |
723 | dentry, oflag, mode, | |
564f6993 | 724 | u_attr ? &attr : NULL); |
1da177e4 | 725 | } |
7c7dce92 AV |
726 | } else { |
727 | error = -ENOENT; | |
728 | if (!dentry->d_inode) | |
729 | goto out; | |
5a190ae6 | 730 | audit_inode(name, dentry); |
614b84cf | 731 | filp = do_open(ipc_ns, dentry, oflag); |
7c7dce92 | 732 | } |
1da177e4 LT |
733 | |
734 | if (IS_ERR(filp)) { | |
735 | error = PTR_ERR(filp); | |
736 | goto out_putfd; | |
737 | } | |
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 | 746 | put_unused_fd(fd); |
1da177e4 LT |
747 | fd = error; |
748 | out_upsem: | |
614b84cf | 749 | mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
750 | out_putname: |
751 | putname(name); | |
752 | return fd; | |
753 | } | |
754 | ||
d5460c99 | 755 | SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name) |
1da177e4 LT |
756 | { |
757 | int err; | |
758 | char *name; | |
759 | struct dentry *dentry; | |
760 | struct inode *inode = NULL; | |
7eafd7c7 | 761 | struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; |
1da177e4 LT |
762 | |
763 | name = getname(u_name); | |
764 | if (IS_ERR(name)) | |
765 | return PTR_ERR(name); | |
766 | ||
614b84cf | 767 | mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex, |
7a434814 | 768 | I_MUTEX_PARENT); |
614b84cf | 769 | dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name)); |
1da177e4 LT |
770 | if (IS_ERR(dentry)) { |
771 | err = PTR_ERR(dentry); | |
772 | goto out_unlock; | |
773 | } | |
774 | ||
775 | if (!dentry->d_inode) { | |
776 | err = -ENOENT; | |
777 | goto out_err; | |
778 | } | |
779 | ||
780 | inode = dentry->d_inode; | |
781 | if (inode) | |
782 | atomic_inc(&inode->i_count); | |
614b84cf | 783 | err = mnt_want_write(ipc_ns->mq_mnt); |
0622753b DH |
784 | if (err) |
785 | goto out_err; | |
1da177e4 | 786 | err = vfs_unlink(dentry->d_parent->d_inode, dentry); |
614b84cf | 787 | mnt_drop_write(ipc_ns->mq_mnt); |
1da177e4 LT |
788 | out_err: |
789 | dput(dentry); | |
790 | ||
791 | out_unlock: | |
614b84cf | 792 | mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
793 | putname(name); |
794 | if (inode) | |
795 | iput(inode); | |
796 | ||
797 | return err; | |
798 | } | |
799 | ||
800 | /* Pipelined send and receive functions. | |
801 | * | |
802 | * If a receiver finds no waiting message, then it registers itself in the | |
803 | * list of waiting receivers. A sender checks that list before adding the new | |
804 | * message into the message array. If there is a waiting receiver, then it | |
805 | * bypasses the message array and directly hands the message over to the | |
806 | * receiver. | |
807 | * The receiver accepts the message and returns without grabbing the queue | |
808 | * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers | |
809 | * are necessary. The same algorithm is used for sysv semaphores, see | |
7b7a317c | 810 | * ipc/sem.c for more details. |
1da177e4 LT |
811 | * |
812 | * The same algorithm is used for senders. | |
813 | */ | |
814 | ||
815 | /* pipelined_send() - send a message directly to the task waiting in | |
816 | * sys_mq_timedreceive() (without inserting message into a queue). | |
817 | */ | |
818 | static inline void pipelined_send(struct mqueue_inode_info *info, | |
819 | struct msg_msg *message, | |
820 | struct ext_wait_queue *receiver) | |
821 | { | |
822 | receiver->msg = message; | |
823 | list_del(&receiver->list); | |
824 | receiver->state = STATE_PENDING; | |
825 | wake_up_process(receiver->task); | |
d59dd462 | 826 | smp_wmb(); |
1da177e4 LT |
827 | receiver->state = STATE_READY; |
828 | } | |
829 | ||
830 | /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() | |
831 | * gets its message and put to the queue (we have one free place for sure). */ | |
832 | static inline void pipelined_receive(struct mqueue_inode_info *info) | |
833 | { | |
834 | struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND); | |
835 | ||
836 | if (!sender) { | |
837 | /* for poll */ | |
838 | wake_up_interruptible(&info->wait_q); | |
839 | return; | |
840 | } | |
841 | msg_insert(sender->msg, info); | |
842 | list_del(&sender->list); | |
843 | sender->state = STATE_PENDING; | |
844 | wake_up_process(sender->task); | |
d59dd462 | 845 | smp_wmb(); |
1da177e4 LT |
846 | sender->state = STATE_READY; |
847 | } | |
848 | ||
c4ea37c2 HC |
849 | SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr, |
850 | size_t, msg_len, unsigned int, msg_prio, | |
851 | const struct timespec __user *, u_abs_timeout) | |
1da177e4 LT |
852 | { |
853 | struct file *filp; | |
854 | struct inode *inode; | |
855 | struct ext_wait_queue wait; | |
856 | struct ext_wait_queue *receiver; | |
857 | struct msg_msg *msg_ptr; | |
858 | struct mqueue_inode_info *info; | |
c32c8af4 | 859 | struct timespec ts, *p = NULL; |
1da177e4 LT |
860 | long timeout; |
861 | int ret; | |
862 | ||
c32c8af4 AV |
863 | if (u_abs_timeout) { |
864 | if (copy_from_user(&ts, u_abs_timeout, | |
865 | sizeof(struct timespec))) | |
866 | return -EFAULT; | |
867 | p = &ts; | |
868 | } | |
20ca73bc | 869 | |
1da177e4 LT |
870 | if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX)) |
871 | return -EINVAL; | |
872 | ||
c32c8af4 AV |
873 | audit_mq_sendrecv(mqdes, msg_len, msg_prio, p); |
874 | timeout = prepare_timeout(p); | |
1da177e4 LT |
875 | |
876 | ret = -EBADF; | |
877 | filp = fget(mqdes); | |
878 | if (unlikely(!filp)) | |
879 | goto out; | |
880 | ||
6d63079a | 881 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
882 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
883 | goto out_fput; | |
884 | info = MQUEUE_I(inode); | |
5a190ae6 | 885 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
886 | |
887 | if (unlikely(!(filp->f_mode & FMODE_WRITE))) | |
888 | goto out_fput; | |
889 | ||
890 | if (unlikely(msg_len > info->attr.mq_msgsize)) { | |
891 | ret = -EMSGSIZE; | |
892 | goto out_fput; | |
893 | } | |
894 | ||
895 | /* First try to allocate memory, before doing anything with | |
896 | * existing queues. */ | |
897 | msg_ptr = load_msg(u_msg_ptr, msg_len); | |
898 | if (IS_ERR(msg_ptr)) { | |
899 | ret = PTR_ERR(msg_ptr); | |
900 | goto out_fput; | |
901 | } | |
902 | msg_ptr->m_ts = msg_len; | |
903 | msg_ptr->m_type = msg_prio; | |
904 | ||
905 | spin_lock(&info->lock); | |
906 | ||
907 | if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) { | |
908 | if (filp->f_flags & O_NONBLOCK) { | |
909 | spin_unlock(&info->lock); | |
910 | ret = -EAGAIN; | |
911 | } else if (unlikely(timeout < 0)) { | |
912 | spin_unlock(&info->lock); | |
913 | ret = timeout; | |
914 | } else { | |
915 | wait.task = current; | |
916 | wait.msg = (void *) msg_ptr; | |
917 | wait.state = STATE_NONE; | |
918 | ret = wq_sleep(info, SEND, timeout, &wait); | |
919 | } | |
920 | if (ret < 0) | |
921 | free_msg(msg_ptr); | |
922 | } else { | |
923 | receiver = wq_get_first_waiter(info, RECV); | |
924 | if (receiver) { | |
925 | pipelined_send(info, msg_ptr, receiver); | |
926 | } else { | |
927 | /* adds message to the queue */ | |
928 | msg_insert(msg_ptr, info); | |
929 | __do_notify(info); | |
930 | } | |
931 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
932 | CURRENT_TIME; | |
933 | spin_unlock(&info->lock); | |
934 | ret = 0; | |
935 | } | |
936 | out_fput: | |
937 | fput(filp); | |
938 | out: | |
939 | return ret; | |
940 | } | |
941 | ||
c4ea37c2 HC |
942 | SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr, |
943 | size_t, msg_len, unsigned int __user *, u_msg_prio, | |
944 | const struct timespec __user *, u_abs_timeout) | |
1da177e4 LT |
945 | { |
946 | long timeout; | |
947 | ssize_t ret; | |
948 | struct msg_msg *msg_ptr; | |
949 | struct file *filp; | |
950 | struct inode *inode; | |
951 | struct mqueue_inode_info *info; | |
952 | struct ext_wait_queue wait; | |
c32c8af4 | 953 | struct timespec ts, *p = NULL; |
1da177e4 | 954 | |
c32c8af4 AV |
955 | if (u_abs_timeout) { |
956 | if (copy_from_user(&ts, u_abs_timeout, | |
957 | sizeof(struct timespec))) | |
958 | return -EFAULT; | |
959 | p = &ts; | |
960 | } | |
20ca73bc | 961 | |
c32c8af4 AV |
962 | audit_mq_sendrecv(mqdes, msg_len, 0, p); |
963 | timeout = prepare_timeout(p); | |
1da177e4 LT |
964 | |
965 | ret = -EBADF; | |
966 | filp = fget(mqdes); | |
967 | if (unlikely(!filp)) | |
968 | goto out; | |
969 | ||
6d63079a | 970 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
971 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
972 | goto out_fput; | |
973 | info = MQUEUE_I(inode); | |
5a190ae6 | 974 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
975 | |
976 | if (unlikely(!(filp->f_mode & FMODE_READ))) | |
977 | goto out_fput; | |
978 | ||
979 | /* checks if buffer is big enough */ | |
980 | if (unlikely(msg_len < info->attr.mq_msgsize)) { | |
981 | ret = -EMSGSIZE; | |
982 | goto out_fput; | |
983 | } | |
984 | ||
985 | spin_lock(&info->lock); | |
986 | if (info->attr.mq_curmsgs == 0) { | |
987 | if (filp->f_flags & O_NONBLOCK) { | |
988 | spin_unlock(&info->lock); | |
989 | ret = -EAGAIN; | |
990 | msg_ptr = NULL; | |
991 | } else if (unlikely(timeout < 0)) { | |
992 | spin_unlock(&info->lock); | |
993 | ret = timeout; | |
994 | msg_ptr = NULL; | |
995 | } else { | |
996 | wait.task = current; | |
997 | wait.state = STATE_NONE; | |
998 | ret = wq_sleep(info, RECV, timeout, &wait); | |
999 | msg_ptr = wait.msg; | |
1000 | } | |
1001 | } else { | |
1002 | msg_ptr = msg_get(info); | |
1003 | ||
1004 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
1005 | CURRENT_TIME; | |
1006 | ||
1007 | /* There is now free space in queue. */ | |
1008 | pipelined_receive(info); | |
1009 | spin_unlock(&info->lock); | |
1010 | ret = 0; | |
1011 | } | |
1012 | if (ret == 0) { | |
1013 | ret = msg_ptr->m_ts; | |
1014 | ||
1015 | if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) || | |
1016 | store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) { | |
1017 | ret = -EFAULT; | |
1018 | } | |
1019 | free_msg(msg_ptr); | |
1020 | } | |
1021 | out_fput: | |
1022 | fput(filp); | |
1023 | out: | |
1024 | return ret; | |
1025 | } | |
1026 | ||
1027 | /* | |
1028 | * Notes: the case when user wants us to deregister (with NULL as pointer) | |
1029 | * and he isn't currently owner of notification, will be silently discarded. | |
1030 | * It isn't explicitly defined in the POSIX. | |
1031 | */ | |
c4ea37c2 HC |
1032 | SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes, |
1033 | const struct sigevent __user *, u_notification) | |
1da177e4 LT |
1034 | { |
1035 | int ret; | |
1036 | struct file *filp; | |
1037 | struct sock *sock; | |
1038 | struct inode *inode; | |
1039 | struct sigevent notification; | |
1040 | struct mqueue_inode_info *info; | |
1041 | struct sk_buff *nc; | |
1042 | ||
20114f71 | 1043 | if (u_notification) { |
1da177e4 LT |
1044 | if (copy_from_user(¬ification, u_notification, |
1045 | sizeof(struct sigevent))) | |
1046 | return -EFAULT; | |
20114f71 AV |
1047 | } |
1048 | ||
1049 | audit_mq_notify(mqdes, u_notification ? ¬ification : NULL); | |
1da177e4 | 1050 | |
20114f71 AV |
1051 | nc = NULL; |
1052 | sock = NULL; | |
1053 | if (u_notification != NULL) { | |
1da177e4 LT |
1054 | if (unlikely(notification.sigev_notify != SIGEV_NONE && |
1055 | notification.sigev_notify != SIGEV_SIGNAL && | |
1056 | notification.sigev_notify != SIGEV_THREAD)) | |
1057 | return -EINVAL; | |
1058 | if (notification.sigev_notify == SIGEV_SIGNAL && | |
7ed20e1a | 1059 | !valid_signal(notification.sigev_signo)) { |
1da177e4 LT |
1060 | return -EINVAL; |
1061 | } | |
1062 | if (notification.sigev_notify == SIGEV_THREAD) { | |
c3d8d1e3 PM |
1063 | long timeo; |
1064 | ||
1da177e4 LT |
1065 | /* create the notify skb */ |
1066 | nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL); | |
1067 | ret = -ENOMEM; | |
1068 | if (!nc) | |
1069 | goto out; | |
1070 | ret = -EFAULT; | |
1071 | if (copy_from_user(nc->data, | |
1072 | notification.sigev_value.sival_ptr, | |
1073 | NOTIFY_COOKIE_LEN)) { | |
1074 | goto out; | |
1075 | } | |
1076 | ||
1077 | /* TODO: add a header? */ | |
1078 | skb_put(nc, NOTIFY_COOKIE_LEN); | |
1079 | /* and attach it to the socket */ | |
1080 | retry: | |
1081 | filp = fget(notification.sigev_signo); | |
1082 | ret = -EBADF; | |
1083 | if (!filp) | |
1084 | goto out; | |
1085 | sock = netlink_getsockbyfilp(filp); | |
1086 | fput(filp); | |
1087 | if (IS_ERR(sock)) { | |
1088 | ret = PTR_ERR(sock); | |
1089 | sock = NULL; | |
1090 | goto out; | |
1091 | } | |
1092 | ||
c3d8d1e3 | 1093 | timeo = MAX_SCHEDULE_TIMEOUT; |
9457afee | 1094 | ret = netlink_attachskb(sock, nc, &timeo, NULL); |
1da177e4 LT |
1095 | if (ret == 1) |
1096 | goto retry; | |
1097 | if (ret) { | |
1098 | sock = NULL; | |
1099 | nc = NULL; | |
1100 | goto out; | |
1101 | } | |
1102 | } | |
1103 | } | |
1104 | ||
1105 | ret = -EBADF; | |
1106 | filp = fget(mqdes); | |
1107 | if (!filp) | |
1108 | goto out; | |
1109 | ||
6d63079a | 1110 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1111 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1112 | goto out_fput; | |
1113 | info = MQUEUE_I(inode); | |
1114 | ||
1115 | ret = 0; | |
1116 | spin_lock(&info->lock); | |
1117 | if (u_notification == NULL) { | |
a03fcb73 | 1118 | if (info->notify_owner == task_tgid(current)) { |
1da177e4 LT |
1119 | remove_notification(info); |
1120 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1121 | } | |
a03fcb73 | 1122 | } else if (info->notify_owner != NULL) { |
1da177e4 LT |
1123 | ret = -EBUSY; |
1124 | } else { | |
1125 | switch (notification.sigev_notify) { | |
1126 | case SIGEV_NONE: | |
1127 | info->notify.sigev_notify = SIGEV_NONE; | |
1128 | break; | |
1129 | case SIGEV_THREAD: | |
1130 | info->notify_sock = sock; | |
1131 | info->notify_cookie = nc; | |
1132 | sock = NULL; | |
1133 | nc = NULL; | |
1134 | info->notify.sigev_notify = SIGEV_THREAD; | |
1135 | break; | |
1136 | case SIGEV_SIGNAL: | |
1137 | info->notify.sigev_signo = notification.sigev_signo; | |
1138 | info->notify.sigev_value = notification.sigev_value; | |
1139 | info->notify.sigev_notify = SIGEV_SIGNAL; | |
1140 | break; | |
1141 | } | |
a03fcb73 CLG |
1142 | |
1143 | info->notify_owner = get_pid(task_tgid(current)); | |
1da177e4 LT |
1144 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1145 | } | |
1146 | spin_unlock(&info->lock); | |
1147 | out_fput: | |
1148 | fput(filp); | |
1149 | out: | |
1150 | if (sock) { | |
1151 | netlink_detachskb(sock, nc); | |
1152 | } else if (nc) { | |
1153 | dev_kfree_skb(nc); | |
1154 | } | |
1155 | return ret; | |
1156 | } | |
1157 | ||
c4ea37c2 HC |
1158 | SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes, |
1159 | const struct mq_attr __user *, u_mqstat, | |
1160 | struct mq_attr __user *, u_omqstat) | |
1da177e4 LT |
1161 | { |
1162 | int ret; | |
1163 | struct mq_attr mqstat, omqstat; | |
1164 | struct file *filp; | |
1165 | struct inode *inode; | |
1166 | struct mqueue_inode_info *info; | |
1167 | ||
1168 | if (u_mqstat != NULL) { | |
1169 | if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr))) | |
1170 | return -EFAULT; | |
1171 | if (mqstat.mq_flags & (~O_NONBLOCK)) | |
1172 | return -EINVAL; | |
1173 | } | |
1174 | ||
1175 | ret = -EBADF; | |
1176 | filp = fget(mqdes); | |
1177 | if (!filp) | |
1178 | goto out; | |
1179 | ||
6d63079a | 1180 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1181 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1182 | goto out_fput; | |
1183 | info = MQUEUE_I(inode); | |
1184 | ||
1185 | spin_lock(&info->lock); | |
1186 | ||
1187 | omqstat = info->attr; | |
1188 | omqstat.mq_flags = filp->f_flags & O_NONBLOCK; | |
1189 | if (u_mqstat) { | |
7392906e | 1190 | audit_mq_getsetattr(mqdes, &mqstat); |
db1dd4d3 | 1191 | spin_lock(&filp->f_lock); |
1da177e4 LT |
1192 | if (mqstat.mq_flags & O_NONBLOCK) |
1193 | filp->f_flags |= O_NONBLOCK; | |
1194 | else | |
1195 | filp->f_flags &= ~O_NONBLOCK; | |
db1dd4d3 | 1196 | spin_unlock(&filp->f_lock); |
1da177e4 LT |
1197 | |
1198 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1199 | } | |
1200 | ||
1201 | spin_unlock(&info->lock); | |
1202 | ||
1203 | ret = 0; | |
1204 | if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat, | |
1205 | sizeof(struct mq_attr))) | |
1206 | ret = -EFAULT; | |
1207 | ||
1208 | out_fput: | |
1209 | fput(filp); | |
1210 | out: | |
1211 | return ret; | |
1212 | } | |
1213 | ||
92e1d5be | 1214 | static const struct inode_operations mqueue_dir_inode_operations = { |
1da177e4 LT |
1215 | .lookup = simple_lookup, |
1216 | .create = mqueue_create, | |
1217 | .unlink = mqueue_unlink, | |
1218 | }; | |
1219 | ||
9a32144e | 1220 | static const struct file_operations mqueue_file_operations = { |
1da177e4 LT |
1221 | .flush = mqueue_flush_file, |
1222 | .poll = mqueue_poll_file, | |
1223 | .read = mqueue_read_file, | |
1224 | }; | |
1225 | ||
b87221de | 1226 | static const struct super_operations mqueue_super_ops = { |
1da177e4 LT |
1227 | .alloc_inode = mqueue_alloc_inode, |
1228 | .destroy_inode = mqueue_destroy_inode, | |
1229 | .statfs = simple_statfs, | |
1230 | .delete_inode = mqueue_delete_inode, | |
1231 | .drop_inode = generic_delete_inode, | |
1232 | }; | |
1233 | ||
1234 | static struct file_system_type mqueue_fs_type = { | |
1235 | .name = "mqueue", | |
1236 | .get_sb = mqueue_get_sb, | |
1237 | .kill_sb = kill_litter_super, | |
1238 | }; | |
1239 | ||
7eafd7c7 SH |
1240 | int mq_init_ns(struct ipc_namespace *ns) |
1241 | { | |
1242 | ns->mq_queues_count = 0; | |
1243 | ns->mq_queues_max = DFLT_QUEUESMAX; | |
1244 | ns->mq_msg_max = DFLT_MSGMAX; | |
1245 | ns->mq_msgsize_max = DFLT_MSGSIZEMAX; | |
1246 | ||
1247 | ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns); | |
1248 | if (IS_ERR(ns->mq_mnt)) { | |
1249 | int err = PTR_ERR(ns->mq_mnt); | |
1250 | ns->mq_mnt = NULL; | |
1251 | return err; | |
1252 | } | |
1253 | return 0; | |
1254 | } | |
1255 | ||
1256 | void mq_clear_sbinfo(struct ipc_namespace *ns) | |
1257 | { | |
1258 | ns->mq_mnt->mnt_sb->s_fs_info = NULL; | |
1259 | } | |
1260 | ||
1261 | void mq_put_mnt(struct ipc_namespace *ns) | |
1262 | { | |
1263 | mntput(ns->mq_mnt); | |
1264 | } | |
1265 | ||
1da177e4 LT |
1266 | static int __init init_mqueue_fs(void) |
1267 | { | |
1268 | int error; | |
1269 | ||
1270 | mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache", | |
1271 | sizeof(struct mqueue_inode_info), 0, | |
20c2df83 | 1272 | SLAB_HWCACHE_ALIGN, init_once); |
1da177e4 LT |
1273 | if (mqueue_inode_cachep == NULL) |
1274 | return -ENOMEM; | |
1275 | ||
1276 | /* ignore failues - they are not fatal */ | |
bdc8e5f8 | 1277 | mq_sysctl_table = mq_register_sysctl_table(); |
1da177e4 LT |
1278 | |
1279 | error = register_filesystem(&mqueue_fs_type); | |
1280 | if (error) | |
1281 | goto out_sysctl; | |
1282 | ||
7eafd7c7 SH |
1283 | spin_lock_init(&mq_lock); |
1284 | ||
1285 | init_ipc_ns.mq_mnt = kern_mount_data(&mqueue_fs_type, &init_ipc_ns); | |
614b84cf SH |
1286 | if (IS_ERR(init_ipc_ns.mq_mnt)) { |
1287 | error = PTR_ERR(init_ipc_ns.mq_mnt); | |
1da177e4 LT |
1288 | goto out_filesystem; |
1289 | } | |
1290 | ||
1da177e4 LT |
1291 | return 0; |
1292 | ||
1293 | out_filesystem: | |
1294 | unregister_filesystem(&mqueue_fs_type); | |
1295 | out_sysctl: | |
1296 | if (mq_sysctl_table) | |
1297 | unregister_sysctl_table(mq_sysctl_table); | |
1a1d92c1 | 1298 | kmem_cache_destroy(mqueue_inode_cachep); |
1da177e4 LT |
1299 | return error; |
1300 | } | |
1301 | ||
1302 | __initcall(init_mqueue_fs); |