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1/*
2 * linux/fs/fcntl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/syscalls.h>
8#include <linux/init.h>
9#include <linux/mm.h>
10#include <linux/fs.h>
11#include <linux/file.h>
12#include <linux/fdtable.h>
13#include <linux/capability.h>
14#include <linux/dnotify.h>
15#include <linux/slab.h>
16#include <linux/module.h>
17#include <linux/pipe_fs_i.h>
18#include <linux/security.h>
19#include <linux/ptrace.h>
20#include <linux/signal.h>
21#include <linux/rcupdate.h>
22#include <linux/pid_namespace.h>
23#include <linux/user_namespace.h>
24#include <linux/shmem_fs.h>
25
26#include <asm/poll.h>
27#include <asm/siginfo.h>
28#include <asm/uaccess.h>
29
30#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
31
32static int setfl(int fd, struct file * filp, unsigned long arg)
33{
34 struct inode * inode = file_inode(filp);
35 int error = 0;
36
37 /*
38 * O_APPEND cannot be cleared if the file is marked as append-only
39 * and the file is open for write.
40 */
41 if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode))
42 return -EPERM;
43
44 /* O_NOATIME can only be set by the owner or superuser */
45 if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
46 if (!inode_owner_or_capable(inode))
47 return -EPERM;
48
49 /* required for strict SunOS emulation */
50 if (O_NONBLOCK != O_NDELAY)
51 if (arg & O_NDELAY)
52 arg |= O_NONBLOCK;
53
54 /* Pipe packetized mode is controlled by O_DIRECT flag */
55 if (!S_ISFIFO(filp->f_inode->i_mode) && (arg & O_DIRECT)) {
56 if (!filp->f_mapping || !filp->f_mapping->a_ops ||
57 !filp->f_mapping->a_ops->direct_IO)
58 return -EINVAL;
59 }
60
61 if (filp->f_op->check_flags)
62 error = filp->f_op->check_flags(arg);
63 if (error)
64 return error;
65
66 /*
67 * ->fasync() is responsible for setting the FASYNC bit.
68 */
69 if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op->fasync) {
70 error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
71 if (error < 0)
72 goto out;
73 if (error > 0)
74 error = 0;
75 }
76 spin_lock(&filp->f_lock);
77 filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
78 spin_unlock(&filp->f_lock);
79
80 out:
81 return error;
82}
83
84static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
85 int force)
86{
87 write_lock_irq(&filp->f_owner.lock);
88 if (force || !filp->f_owner.pid) {
89 put_pid(filp->f_owner.pid);
90 filp->f_owner.pid = get_pid(pid);
91 filp->f_owner.pid_type = type;
92
93 if (pid) {
94 const struct cred *cred = current_cred();
95 filp->f_owner.uid = cred->uid;
96 filp->f_owner.euid = cred->euid;
97 }
98 }
99 write_unlock_irq(&filp->f_owner.lock);
100}
101
102void __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
103 int force)
104{
105 security_file_set_fowner(filp);
106 f_modown(filp, pid, type, force);
107}
108EXPORT_SYMBOL(__f_setown);
109
110void f_setown(struct file *filp, unsigned long arg, int force)
111{
112 enum pid_type type;
113 struct pid *pid;
114 int who = arg;
115 type = PIDTYPE_PID;
116 if (who < 0) {
117 type = PIDTYPE_PGID;
118 who = -who;
119 }
120 rcu_read_lock();
121 pid = find_vpid(who);
122 __f_setown(filp, pid, type, force);
123 rcu_read_unlock();
124}
125EXPORT_SYMBOL(f_setown);
126
127void f_delown(struct file *filp)
128{
129 f_modown(filp, NULL, PIDTYPE_PID, 1);
130}
131
132pid_t f_getown(struct file *filp)
133{
134 pid_t pid;
135 read_lock(&filp->f_owner.lock);
136 pid = pid_vnr(filp->f_owner.pid);
137 if (filp->f_owner.pid_type == PIDTYPE_PGID)
138 pid = -pid;
139 read_unlock(&filp->f_owner.lock);
140 return pid;
141}
142
143static int f_setown_ex(struct file *filp, unsigned long arg)
144{
145 struct f_owner_ex __user *owner_p = (void __user *)arg;
146 struct f_owner_ex owner;
147 struct pid *pid;
148 int type;
149 int ret;
150
151 ret = copy_from_user(&owner, owner_p, sizeof(owner));
152 if (ret)
153 return -EFAULT;
154
155 switch (owner.type) {
156 case F_OWNER_TID:
157 type = PIDTYPE_MAX;
158 break;
159
160 case F_OWNER_PID:
161 type = PIDTYPE_PID;
162 break;
163
164 case F_OWNER_PGRP:
165 type = PIDTYPE_PGID;
166 break;
167
168 default:
169 return -EINVAL;
170 }
171
172 rcu_read_lock();
173 pid = find_vpid(owner.pid);
174 if (owner.pid && !pid)
175 ret = -ESRCH;
176 else
177 __f_setown(filp, pid, type, 1);
178 rcu_read_unlock();
179
180 return ret;
181}
182
183static int f_getown_ex(struct file *filp, unsigned long arg)
184{
185 struct f_owner_ex __user *owner_p = (void __user *)arg;
186 struct f_owner_ex owner;
187 int ret = 0;
188
189 read_lock(&filp->f_owner.lock);
190 owner.pid = pid_vnr(filp->f_owner.pid);
191 switch (filp->f_owner.pid_type) {
192 case PIDTYPE_MAX:
193 owner.type = F_OWNER_TID;
194 break;
195
196 case PIDTYPE_PID:
197 owner.type = F_OWNER_PID;
198 break;
199
200 case PIDTYPE_PGID:
201 owner.type = F_OWNER_PGRP;
202 break;
203
204 default:
205 WARN_ON(1);
206 ret = -EINVAL;
207 break;
208 }
209 read_unlock(&filp->f_owner.lock);
210
211 if (!ret) {
212 ret = copy_to_user(owner_p, &owner, sizeof(owner));
213 if (ret)
214 ret = -EFAULT;
215 }
216 return ret;
217}
218
219#ifdef CONFIG_CHECKPOINT_RESTORE
220static int f_getowner_uids(struct file *filp, unsigned long arg)
221{
222 struct user_namespace *user_ns = current_user_ns();
223 uid_t __user *dst = (void __user *)arg;
224 uid_t src[2];
225 int err;
226
227 read_lock(&filp->f_owner.lock);
228 src[0] = from_kuid(user_ns, filp->f_owner.uid);
229 src[1] = from_kuid(user_ns, filp->f_owner.euid);
230 read_unlock(&filp->f_owner.lock);
231
232 err = put_user(src[0], &dst[0]);
233 err |= put_user(src[1], &dst[1]);
234
235 return err;
236}
237#else
238static int f_getowner_uids(struct file *filp, unsigned long arg)
239{
240 return -EINVAL;
241}
242#endif
243
244static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
245 struct file *filp)
246{
247 long err = -EINVAL;
248
249 switch (cmd) {
250 case F_DUPFD:
251 err = f_dupfd(arg, filp, 0);
252 break;
253 case F_DUPFD_CLOEXEC:
254 err = f_dupfd(arg, filp, O_CLOEXEC);
255 break;
256 case F_GETFD:
257 err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
258 break;
259 case F_SETFD:
260 err = 0;
261 set_close_on_exec(fd, arg & FD_CLOEXEC);
262 break;
263 case F_GETFL:
264 err = filp->f_flags;
265 break;
266 case F_SETFL:
267 err = setfl(fd, filp, arg);
268 break;
269#if BITS_PER_LONG != 32
270 /* 32-bit arches must use fcntl64() */
271 case F_OFD_GETLK:
272#endif
273 case F_GETLK:
274 err = fcntl_getlk(filp, cmd, (struct flock __user *) arg);
275 break;
276#if BITS_PER_LONG != 32
277 /* 32-bit arches must use fcntl64() */
278 case F_OFD_SETLK:
279 case F_OFD_SETLKW:
280#endif
281 /* Fallthrough */
282 case F_SETLK:
283 case F_SETLKW:
284 err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
285 break;
286 case F_GETOWN:
287 /*
288 * XXX If f_owner is a process group, the
289 * negative return value will get converted
290 * into an error. Oops. If we keep the
291 * current syscall conventions, the only way
292 * to fix this will be in libc.
293 */
294 err = f_getown(filp);
295 force_successful_syscall_return();
296 break;
297 case F_SETOWN:
298 f_setown(filp, arg, 1);
299 err = 0;
300 break;
301 case F_GETOWN_EX:
302 err = f_getown_ex(filp, arg);
303 break;
304 case F_SETOWN_EX:
305 err = f_setown_ex(filp, arg);
306 break;
307 case F_GETOWNER_UIDS:
308 err = f_getowner_uids(filp, arg);
309 break;
310 case F_GETSIG:
311 err = filp->f_owner.signum;
312 break;
313 case F_SETSIG:
314 /* arg == 0 restores default behaviour. */
315 if (!valid_signal(arg)) {
316 break;
317 }
318 err = 0;
319 filp->f_owner.signum = arg;
320 break;
321 case F_GETLEASE:
322 err = fcntl_getlease(filp);
323 break;
324 case F_SETLEASE:
325 err = fcntl_setlease(fd, filp, arg);
326 break;
327 case F_NOTIFY:
328 err = fcntl_dirnotify(fd, filp, arg);
329 break;
330 case F_SETPIPE_SZ:
331 case F_GETPIPE_SZ:
332 err = pipe_fcntl(filp, cmd, arg);
333 break;
334 case F_ADD_SEALS:
335 case F_GET_SEALS:
336 err = shmem_fcntl(filp, cmd, arg);
337 break;
338 default:
339 break;
340 }
341 return err;
342}
343
344static int check_fcntl_cmd(unsigned cmd)
345{
346 switch (cmd) {
347 case F_DUPFD:
348 case F_DUPFD_CLOEXEC:
349 case F_GETFD:
350 case F_SETFD:
351 case F_GETFL:
352 return 1;
353 }
354 return 0;
355}
356
357SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
358{
359 struct fd f = fdget_raw(fd);
360 long err = -EBADF;
361
362 if (!f.file)
363 goto out;
364
365 if (unlikely(f.file->f_mode & FMODE_PATH)) {
366 if (!check_fcntl_cmd(cmd))
367 goto out1;
368 }
369
370 err = security_file_fcntl(f.file, cmd, arg);
371 if (!err)
372 err = do_fcntl(fd, cmd, arg, f.file);
373
374out1:
375 fdput(f);
376out:
377 return err;
378}
379
380#if BITS_PER_LONG == 32
381SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
382 unsigned long, arg)
383{
384 struct fd f = fdget_raw(fd);
385 long err = -EBADF;
386
387 if (!f.file)
388 goto out;
389
390 if (unlikely(f.file->f_mode & FMODE_PATH)) {
391 if (!check_fcntl_cmd(cmd))
392 goto out1;
393 }
394
395 err = security_file_fcntl(f.file, cmd, arg);
396 if (err)
397 goto out1;
398
399 switch (cmd) {
400 case F_GETLK64:
401 case F_OFD_GETLK:
402 err = fcntl_getlk64(f.file, cmd, (struct flock64 __user *) arg);
403 break;
404 case F_SETLK64:
405 case F_SETLKW64:
406 case F_OFD_SETLK:
407 case F_OFD_SETLKW:
408 err = fcntl_setlk64(fd, f.file, cmd,
409 (struct flock64 __user *) arg);
410 break;
411 default:
412 err = do_fcntl(fd, cmd, arg, f.file);
413 break;
414 }
415out1:
416 fdput(f);
417out:
418 return err;
419}
420#endif
421
422/* Table to convert sigio signal codes into poll band bitmaps */
423
424static const long band_table[NSIGPOLL] = {
425 POLLIN | POLLRDNORM, /* POLL_IN */
426 POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */
427 POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */
428 POLLERR, /* POLL_ERR */
429 POLLPRI | POLLRDBAND, /* POLL_PRI */
430 POLLHUP | POLLERR /* POLL_HUP */
431};
432
433static inline int sigio_perm(struct task_struct *p,
434 struct fown_struct *fown, int sig)
435{
436 const struct cred *cred;
437 int ret;
438
439 rcu_read_lock();
440 cred = __task_cred(p);
441 ret = ((uid_eq(fown->euid, GLOBAL_ROOT_UID) ||
442 uid_eq(fown->euid, cred->suid) || uid_eq(fown->euid, cred->uid) ||
443 uid_eq(fown->uid, cred->suid) || uid_eq(fown->uid, cred->uid)) &&
444 !security_file_send_sigiotask(p, fown, sig));
445 rcu_read_unlock();
446 return ret;
447}
448
449static void send_sigio_to_task(struct task_struct *p,
450 struct fown_struct *fown,
451 int fd, int reason, int group)
452{
453 /*
454 * F_SETSIG can change ->signum lockless in parallel, make
455 * sure we read it once and use the same value throughout.
456 */
457 int signum = ACCESS_ONCE(fown->signum);
458
459 if (!sigio_perm(p, fown, signum))
460 return;
461
462 switch (signum) {
463 siginfo_t si;
464 default:
465 /* Queue a rt signal with the appropriate fd as its
466 value. We use SI_SIGIO as the source, not
467 SI_KERNEL, since kernel signals always get
468 delivered even if we can't queue. Failure to
469 queue in this case _should_ be reported; we fall
470 back to SIGIO in that case. --sct */
471 si.si_signo = signum;
472 si.si_errno = 0;
473 si.si_code = reason;
474 /* Make sure we are called with one of the POLL_*
475 reasons, otherwise we could leak kernel stack into
476 userspace. */
477 BUG_ON((reason & __SI_MASK) != __SI_POLL);
478 if (reason - POLL_IN >= NSIGPOLL)
479 si.si_band = ~0L;
480 else
481 si.si_band = band_table[reason - POLL_IN];
482 si.si_fd = fd;
483 if (!do_send_sig_info(signum, &si, p, group))
484 break;
485 /* fall-through: fall back on the old plain SIGIO signal */
486 case 0:
487 do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
488 }
489}
490
491void send_sigio(struct fown_struct *fown, int fd, int band)
492{
493 struct task_struct *p;
494 enum pid_type type;
495 struct pid *pid;
496 int group = 1;
497
498 read_lock(&fown->lock);
499
500 type = fown->pid_type;
501 if (type == PIDTYPE_MAX) {
502 group = 0;
503 type = PIDTYPE_PID;
504 }
505
506 pid = fown->pid;
507 if (!pid)
508 goto out_unlock_fown;
509
510 read_lock(&tasklist_lock);
511 do_each_pid_task(pid, type, p) {
512 send_sigio_to_task(p, fown, fd, band, group);
513 } while_each_pid_task(pid, type, p);
514 read_unlock(&tasklist_lock);
515 out_unlock_fown:
516 read_unlock(&fown->lock);
517}
518
519static void send_sigurg_to_task(struct task_struct *p,
520 struct fown_struct *fown, int group)
521{
522 if (sigio_perm(p, fown, SIGURG))
523 do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
524}
525
526int send_sigurg(struct fown_struct *fown)
527{
528 struct task_struct *p;
529 enum pid_type type;
530 struct pid *pid;
531 int group = 1;
532 int ret = 0;
533
534 read_lock(&fown->lock);
535
536 type = fown->pid_type;
537 if (type == PIDTYPE_MAX) {
538 group = 0;
539 type = PIDTYPE_PID;
540 }
541
542 pid = fown->pid;
543 if (!pid)
544 goto out_unlock_fown;
545
546 ret = 1;
547
548 read_lock(&tasklist_lock);
549 do_each_pid_task(pid, type, p) {
550 send_sigurg_to_task(p, fown, group);
551 } while_each_pid_task(pid, type, p);
552 read_unlock(&tasklist_lock);
553 out_unlock_fown:
554 read_unlock(&fown->lock);
555 return ret;
556}
557
558static DEFINE_SPINLOCK(fasync_lock);
559static struct kmem_cache *fasync_cache __read_mostly;
560
561static void fasync_free_rcu(struct rcu_head *head)
562{
563 kmem_cache_free(fasync_cache,
564 container_of(head, struct fasync_struct, fa_rcu));
565}
566
567/*
568 * Remove a fasync entry. If successfully removed, return
569 * positive and clear the FASYNC flag. If no entry exists,
570 * do nothing and return 0.
571 *
572 * NOTE! It is very important that the FASYNC flag always
573 * match the state "is the filp on a fasync list".
574 *
575 */
576int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
577{
578 struct fasync_struct *fa, **fp;
579 int result = 0;
580
581 spin_lock(&filp->f_lock);
582 spin_lock(&fasync_lock);
583 for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
584 if (fa->fa_file != filp)
585 continue;
586
587 spin_lock_irq(&fa->fa_lock);
588 fa->fa_file = NULL;
589 spin_unlock_irq(&fa->fa_lock);
590
591 *fp = fa->fa_next;
592 call_rcu(&fa->fa_rcu, fasync_free_rcu);
593 filp->f_flags &= ~FASYNC;
594 result = 1;
595 break;
596 }
597 spin_unlock(&fasync_lock);
598 spin_unlock(&filp->f_lock);
599 return result;
600}
601
602struct fasync_struct *fasync_alloc(void)
603{
604 return kmem_cache_alloc(fasync_cache, GFP_KERNEL);
605}
606
607/*
608 * NOTE! This can be used only for unused fasync entries:
609 * entries that actually got inserted on the fasync list
610 * need to be released by rcu - see fasync_remove_entry.
611 */
612void fasync_free(struct fasync_struct *new)
613{
614 kmem_cache_free(fasync_cache, new);
615}
616
617/*
618 * Insert a new entry into the fasync list. Return the pointer to the
619 * old one if we didn't use the new one.
620 *
621 * NOTE! It is very important that the FASYNC flag always
622 * match the state "is the filp on a fasync list".
623 */
624struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)
625{
626 struct fasync_struct *fa, **fp;
627
628 spin_lock(&filp->f_lock);
629 spin_lock(&fasync_lock);
630 for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
631 if (fa->fa_file != filp)
632 continue;
633
634 spin_lock_irq(&fa->fa_lock);
635 fa->fa_fd = fd;
636 spin_unlock_irq(&fa->fa_lock);
637 goto out;
638 }
639
640 spin_lock_init(&new->fa_lock);
641 new->magic = FASYNC_MAGIC;
642 new->fa_file = filp;
643 new->fa_fd = fd;
644 new->fa_next = *fapp;
645 rcu_assign_pointer(*fapp, new);
646 filp->f_flags |= FASYNC;
647
648out:
649 spin_unlock(&fasync_lock);
650 spin_unlock(&filp->f_lock);
651 return fa;
652}
653
654/*
655 * Add a fasync entry. Return negative on error, positive if
656 * added, and zero if did nothing but change an existing one.
657 */
658static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
659{
660 struct fasync_struct *new;
661
662 new = fasync_alloc();
663 if (!new)
664 return -ENOMEM;
665
666 /*
667 * fasync_insert_entry() returns the old (update) entry if
668 * it existed.
669 *
670 * So free the (unused) new entry and return 0 to let the
671 * caller know that we didn't add any new fasync entries.
672 */
673 if (fasync_insert_entry(fd, filp, fapp, new)) {
674 fasync_free(new);
675 return 0;
676 }
677
678 return 1;
679}
680
681/*
682 * fasync_helper() is used by almost all character device drivers
683 * to set up the fasync queue, and for regular files by the file
684 * lease code. It returns negative on error, 0 if it did no changes
685 * and positive if it added/deleted the entry.
686 */
687int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
688{
689 if (!on)
690 return fasync_remove_entry(filp, fapp);
691 return fasync_add_entry(fd, filp, fapp);
692}
693
694EXPORT_SYMBOL(fasync_helper);
695
696/*
697 * rcu_read_lock() is held
698 */
699static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
700{
701 while (fa) {
702 struct fown_struct *fown;
703 unsigned long flags;
704
705 if (fa->magic != FASYNC_MAGIC) {
706 printk(KERN_ERR "kill_fasync: bad magic number in "
707 "fasync_struct!\n");
708 return;
709 }
710 spin_lock_irqsave(&fa->fa_lock, flags);
711 if (fa->fa_file) {
712 fown = &fa->fa_file->f_owner;
713 /* Don't send SIGURG to processes which have not set a
714 queued signum: SIGURG has its own default signalling
715 mechanism. */
716 if (!(sig == SIGURG && fown->signum == 0))
717 send_sigio(fown, fa->fa_fd, band);
718 }
719 spin_unlock_irqrestore(&fa->fa_lock, flags);
720 fa = rcu_dereference(fa->fa_next);
721 }
722}
723
724void kill_fasync(struct fasync_struct **fp, int sig, int band)
725{
726 /* First a quick test without locking: usually
727 * the list is empty.
728 */
729 if (*fp) {
730 rcu_read_lock();
731 kill_fasync_rcu(rcu_dereference(*fp), sig, band);
732 rcu_read_unlock();
733 }
734}
735EXPORT_SYMBOL(kill_fasync);
736
737static int __init fcntl_init(void)
738{
739 /*
740 * Please add new bits here to ensure allocation uniqueness.
741 * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
742 * is defined as O_NONBLOCK on some platforms and not on others.
743 */
744 BUILD_BUG_ON(21 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
745 O_RDONLY | O_WRONLY | O_RDWR |
746 O_CREAT | O_EXCL | O_NOCTTY |
747 O_TRUNC | O_APPEND | /* O_NONBLOCK | */
748 __O_SYNC | O_DSYNC | FASYNC |
749 O_DIRECT | O_LARGEFILE | O_DIRECTORY |
750 O_NOFOLLOW | O_NOATIME | O_CLOEXEC |
751 __FMODE_EXEC | O_PATH | __O_TMPFILE |
752 __FMODE_NONOTIFY
753 ));
754
755 fasync_cache = kmem_cache_create("fasync_cache",
756 sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
757 return 0;
758}
759
760module_init(fcntl_init)
1/*
2 * linux/fs/fcntl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/syscalls.h>
8#include <linux/init.h>
9#include <linux/mm.h>
10#include <linux/fs.h>
11#include <linux/file.h>
12#include <linux/fdtable.h>
13#include <linux/capability.h>
14#include <linux/dnotify.h>
15#include <linux/slab.h>
16#include <linux/module.h>
17#include <linux/pipe_fs_i.h>
18#include <linux/security.h>
19#include <linux/ptrace.h>
20#include <linux/signal.h>
21#include <linux/rcupdate.h>
22#include <linux/pid_namespace.h>
23
24#include <asm/poll.h>
25#include <asm/siginfo.h>
26#include <asm/uaccess.h>
27
28void set_close_on_exec(unsigned int fd, int flag)
29{
30 struct files_struct *files = current->files;
31 struct fdtable *fdt;
32 spin_lock(&files->file_lock);
33 fdt = files_fdtable(files);
34 if (flag)
35 __set_close_on_exec(fd, fdt);
36 else
37 __clear_close_on_exec(fd, fdt);
38 spin_unlock(&files->file_lock);
39}
40
41static bool get_close_on_exec(unsigned int fd)
42{
43 struct files_struct *files = current->files;
44 struct fdtable *fdt;
45 bool res;
46 rcu_read_lock();
47 fdt = files_fdtable(files);
48 res = close_on_exec(fd, fdt);
49 rcu_read_unlock();
50 return res;
51}
52
53SYSCALL_DEFINE3(dup3, unsigned int, oldfd, unsigned int, newfd, int, flags)
54{
55 int err = -EBADF;
56 struct file * file, *tofree;
57 struct files_struct * files = current->files;
58 struct fdtable *fdt;
59
60 if ((flags & ~O_CLOEXEC) != 0)
61 return -EINVAL;
62
63 if (unlikely(oldfd == newfd))
64 return -EINVAL;
65
66 spin_lock(&files->file_lock);
67 err = expand_files(files, newfd);
68 file = fcheck(oldfd);
69 if (unlikely(!file))
70 goto Ebadf;
71 if (unlikely(err < 0)) {
72 if (err == -EMFILE)
73 goto Ebadf;
74 goto out_unlock;
75 }
76 /*
77 * We need to detect attempts to do dup2() over allocated but still
78 * not finished descriptor. NB: OpenBSD avoids that at the price of
79 * extra work in their equivalent of fget() - they insert struct
80 * file immediately after grabbing descriptor, mark it larval if
81 * more work (e.g. actual opening) is needed and make sure that
82 * fget() treats larval files as absent. Potentially interesting,
83 * but while extra work in fget() is trivial, locking implications
84 * and amount of surgery on open()-related paths in VFS are not.
85 * FreeBSD fails with -EBADF in the same situation, NetBSD "solution"
86 * deadlocks in rather amusing ways, AFAICS. All of that is out of
87 * scope of POSIX or SUS, since neither considers shared descriptor
88 * tables and this condition does not arise without those.
89 */
90 err = -EBUSY;
91 fdt = files_fdtable(files);
92 tofree = fdt->fd[newfd];
93 if (!tofree && fd_is_open(newfd, fdt))
94 goto out_unlock;
95 get_file(file);
96 rcu_assign_pointer(fdt->fd[newfd], file);
97 __set_open_fd(newfd, fdt);
98 if (flags & O_CLOEXEC)
99 __set_close_on_exec(newfd, fdt);
100 else
101 __clear_close_on_exec(newfd, fdt);
102 spin_unlock(&files->file_lock);
103
104 if (tofree)
105 filp_close(tofree, files);
106
107 return newfd;
108
109Ebadf:
110 err = -EBADF;
111out_unlock:
112 spin_unlock(&files->file_lock);
113 return err;
114}
115
116SYSCALL_DEFINE2(dup2, unsigned int, oldfd, unsigned int, newfd)
117{
118 if (unlikely(newfd == oldfd)) { /* corner case */
119 struct files_struct *files = current->files;
120 int retval = oldfd;
121
122 rcu_read_lock();
123 if (!fcheck_files(files, oldfd))
124 retval = -EBADF;
125 rcu_read_unlock();
126 return retval;
127 }
128 return sys_dup3(oldfd, newfd, 0);
129}
130
131SYSCALL_DEFINE1(dup, unsigned int, fildes)
132{
133 int ret = -EBADF;
134 struct file *file = fget_raw(fildes);
135
136 if (file) {
137 ret = get_unused_fd();
138 if (ret >= 0)
139 fd_install(ret, file);
140 else
141 fput(file);
142 }
143 return ret;
144}
145
146#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
147
148static int setfl(int fd, struct file * filp, unsigned long arg)
149{
150 struct inode * inode = filp->f_path.dentry->d_inode;
151 int error = 0;
152
153 /*
154 * O_APPEND cannot be cleared if the file is marked as append-only
155 * and the file is open for write.
156 */
157 if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode))
158 return -EPERM;
159
160 /* O_NOATIME can only be set by the owner or superuser */
161 if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
162 if (!inode_owner_or_capable(inode))
163 return -EPERM;
164
165 /* required for strict SunOS emulation */
166 if (O_NONBLOCK != O_NDELAY)
167 if (arg & O_NDELAY)
168 arg |= O_NONBLOCK;
169
170 if (arg & O_DIRECT) {
171 if (!filp->f_mapping || !filp->f_mapping->a_ops ||
172 !filp->f_mapping->a_ops->direct_IO)
173 return -EINVAL;
174 }
175
176 if (filp->f_op && filp->f_op->check_flags)
177 error = filp->f_op->check_flags(arg);
178 if (error)
179 return error;
180
181 /*
182 * ->fasync() is responsible for setting the FASYNC bit.
183 */
184 if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
185 filp->f_op->fasync) {
186 error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
187 if (error < 0)
188 goto out;
189 if (error > 0)
190 error = 0;
191 }
192 spin_lock(&filp->f_lock);
193 filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
194 spin_unlock(&filp->f_lock);
195
196 out:
197 return error;
198}
199
200static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
201 int force)
202{
203 write_lock_irq(&filp->f_owner.lock);
204 if (force || !filp->f_owner.pid) {
205 put_pid(filp->f_owner.pid);
206 filp->f_owner.pid = get_pid(pid);
207 filp->f_owner.pid_type = type;
208
209 if (pid) {
210 const struct cred *cred = current_cred();
211 filp->f_owner.uid = cred->uid;
212 filp->f_owner.euid = cred->euid;
213 }
214 }
215 write_unlock_irq(&filp->f_owner.lock);
216}
217
218int __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
219 int force)
220{
221 int err;
222
223 err = security_file_set_fowner(filp);
224 if (err)
225 return err;
226
227 f_modown(filp, pid, type, force);
228 return 0;
229}
230EXPORT_SYMBOL(__f_setown);
231
232int f_setown(struct file *filp, unsigned long arg, int force)
233{
234 enum pid_type type;
235 struct pid *pid;
236 int who = arg;
237 int result;
238 type = PIDTYPE_PID;
239 if (who < 0) {
240 type = PIDTYPE_PGID;
241 who = -who;
242 }
243 rcu_read_lock();
244 pid = find_vpid(who);
245 result = __f_setown(filp, pid, type, force);
246 rcu_read_unlock();
247 return result;
248}
249EXPORT_SYMBOL(f_setown);
250
251void f_delown(struct file *filp)
252{
253 f_modown(filp, NULL, PIDTYPE_PID, 1);
254}
255
256pid_t f_getown(struct file *filp)
257{
258 pid_t pid;
259 read_lock(&filp->f_owner.lock);
260 pid = pid_vnr(filp->f_owner.pid);
261 if (filp->f_owner.pid_type == PIDTYPE_PGID)
262 pid = -pid;
263 read_unlock(&filp->f_owner.lock);
264 return pid;
265}
266
267static int f_setown_ex(struct file *filp, unsigned long arg)
268{
269 struct f_owner_ex * __user owner_p = (void * __user)arg;
270 struct f_owner_ex owner;
271 struct pid *pid;
272 int type;
273 int ret;
274
275 ret = copy_from_user(&owner, owner_p, sizeof(owner));
276 if (ret)
277 return -EFAULT;
278
279 switch (owner.type) {
280 case F_OWNER_TID:
281 type = PIDTYPE_MAX;
282 break;
283
284 case F_OWNER_PID:
285 type = PIDTYPE_PID;
286 break;
287
288 case F_OWNER_PGRP:
289 type = PIDTYPE_PGID;
290 break;
291
292 default:
293 return -EINVAL;
294 }
295
296 rcu_read_lock();
297 pid = find_vpid(owner.pid);
298 if (owner.pid && !pid)
299 ret = -ESRCH;
300 else
301 ret = __f_setown(filp, pid, type, 1);
302 rcu_read_unlock();
303
304 return ret;
305}
306
307static int f_getown_ex(struct file *filp, unsigned long arg)
308{
309 struct f_owner_ex * __user owner_p = (void * __user)arg;
310 struct f_owner_ex owner;
311 int ret = 0;
312
313 read_lock(&filp->f_owner.lock);
314 owner.pid = pid_vnr(filp->f_owner.pid);
315 switch (filp->f_owner.pid_type) {
316 case PIDTYPE_MAX:
317 owner.type = F_OWNER_TID;
318 break;
319
320 case PIDTYPE_PID:
321 owner.type = F_OWNER_PID;
322 break;
323
324 case PIDTYPE_PGID:
325 owner.type = F_OWNER_PGRP;
326 break;
327
328 default:
329 WARN_ON(1);
330 ret = -EINVAL;
331 break;
332 }
333 read_unlock(&filp->f_owner.lock);
334
335 if (!ret) {
336 ret = copy_to_user(owner_p, &owner, sizeof(owner));
337 if (ret)
338 ret = -EFAULT;
339 }
340 return ret;
341}
342
343static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
344 struct file *filp)
345{
346 long err = -EINVAL;
347
348 switch (cmd) {
349 case F_DUPFD:
350 case F_DUPFD_CLOEXEC:
351 if (arg >= rlimit(RLIMIT_NOFILE))
352 break;
353 err = alloc_fd(arg, cmd == F_DUPFD_CLOEXEC ? O_CLOEXEC : 0);
354 if (err >= 0) {
355 get_file(filp);
356 fd_install(err, filp);
357 }
358 break;
359 case F_GETFD:
360 err = get_close_on_exec(fd) ? FD_CLOEXEC : 0;
361 break;
362 case F_SETFD:
363 err = 0;
364 set_close_on_exec(fd, arg & FD_CLOEXEC);
365 break;
366 case F_GETFL:
367 err = filp->f_flags;
368 break;
369 case F_SETFL:
370 err = setfl(fd, filp, arg);
371 break;
372 case F_GETLK:
373 err = fcntl_getlk(filp, (struct flock __user *) arg);
374 break;
375 case F_SETLK:
376 case F_SETLKW:
377 err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
378 break;
379 case F_GETOWN:
380 /*
381 * XXX If f_owner is a process group, the
382 * negative return value will get converted
383 * into an error. Oops. If we keep the
384 * current syscall conventions, the only way
385 * to fix this will be in libc.
386 */
387 err = f_getown(filp);
388 force_successful_syscall_return();
389 break;
390 case F_SETOWN:
391 err = f_setown(filp, arg, 1);
392 break;
393 case F_GETOWN_EX:
394 err = f_getown_ex(filp, arg);
395 break;
396 case F_SETOWN_EX:
397 err = f_setown_ex(filp, arg);
398 break;
399 case F_GETSIG:
400 err = filp->f_owner.signum;
401 break;
402 case F_SETSIG:
403 /* arg == 0 restores default behaviour. */
404 if (!valid_signal(arg)) {
405 break;
406 }
407 err = 0;
408 filp->f_owner.signum = arg;
409 break;
410 case F_GETLEASE:
411 err = fcntl_getlease(filp);
412 break;
413 case F_SETLEASE:
414 err = fcntl_setlease(fd, filp, arg);
415 break;
416 case F_NOTIFY:
417 err = fcntl_dirnotify(fd, filp, arg);
418 break;
419 case F_SETPIPE_SZ:
420 case F_GETPIPE_SZ:
421 err = pipe_fcntl(filp, cmd, arg);
422 break;
423 default:
424 break;
425 }
426 return err;
427}
428
429static int check_fcntl_cmd(unsigned cmd)
430{
431 switch (cmd) {
432 case F_DUPFD:
433 case F_DUPFD_CLOEXEC:
434 case F_GETFD:
435 case F_SETFD:
436 case F_GETFL:
437 return 1;
438 }
439 return 0;
440}
441
442SYSCALL_DEFINE3(fcntl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
443{
444 struct file *filp;
445 int fput_needed;
446 long err = -EBADF;
447
448 filp = fget_raw_light(fd, &fput_needed);
449 if (!filp)
450 goto out;
451
452 if (unlikely(filp->f_mode & FMODE_PATH)) {
453 if (!check_fcntl_cmd(cmd))
454 goto out1;
455 }
456
457 err = security_file_fcntl(filp, cmd, arg);
458 if (!err)
459 err = do_fcntl(fd, cmd, arg, filp);
460
461out1:
462 fput_light(filp, fput_needed);
463out:
464 return err;
465}
466
467#if BITS_PER_LONG == 32
468SYSCALL_DEFINE3(fcntl64, unsigned int, fd, unsigned int, cmd,
469 unsigned long, arg)
470{
471 struct file * filp;
472 long err = -EBADF;
473 int fput_needed;
474
475 filp = fget_raw_light(fd, &fput_needed);
476 if (!filp)
477 goto out;
478
479 if (unlikely(filp->f_mode & FMODE_PATH)) {
480 if (!check_fcntl_cmd(cmd))
481 goto out1;
482 }
483
484 err = security_file_fcntl(filp, cmd, arg);
485 if (err)
486 goto out1;
487
488 switch (cmd) {
489 case F_GETLK64:
490 err = fcntl_getlk64(filp, (struct flock64 __user *) arg);
491 break;
492 case F_SETLK64:
493 case F_SETLKW64:
494 err = fcntl_setlk64(fd, filp, cmd,
495 (struct flock64 __user *) arg);
496 break;
497 default:
498 err = do_fcntl(fd, cmd, arg, filp);
499 break;
500 }
501out1:
502 fput_light(filp, fput_needed);
503out:
504 return err;
505}
506#endif
507
508/* Table to convert sigio signal codes into poll band bitmaps */
509
510static const long band_table[NSIGPOLL] = {
511 POLLIN | POLLRDNORM, /* POLL_IN */
512 POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */
513 POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */
514 POLLERR, /* POLL_ERR */
515 POLLPRI | POLLRDBAND, /* POLL_PRI */
516 POLLHUP | POLLERR /* POLL_HUP */
517};
518
519static inline int sigio_perm(struct task_struct *p,
520 struct fown_struct *fown, int sig)
521{
522 const struct cred *cred;
523 int ret;
524
525 rcu_read_lock();
526 cred = __task_cred(p);
527 ret = ((uid_eq(fown->euid, GLOBAL_ROOT_UID) ||
528 uid_eq(fown->euid, cred->suid) || uid_eq(fown->euid, cred->uid) ||
529 uid_eq(fown->uid, cred->suid) || uid_eq(fown->uid, cred->uid)) &&
530 !security_file_send_sigiotask(p, fown, sig));
531 rcu_read_unlock();
532 return ret;
533}
534
535static void send_sigio_to_task(struct task_struct *p,
536 struct fown_struct *fown,
537 int fd, int reason, int group)
538{
539 /*
540 * F_SETSIG can change ->signum lockless in parallel, make
541 * sure we read it once and use the same value throughout.
542 */
543 int signum = ACCESS_ONCE(fown->signum);
544
545 if (!sigio_perm(p, fown, signum))
546 return;
547
548 switch (signum) {
549 siginfo_t si;
550 default:
551 /* Queue a rt signal with the appropriate fd as its
552 value. We use SI_SIGIO as the source, not
553 SI_KERNEL, since kernel signals always get
554 delivered even if we can't queue. Failure to
555 queue in this case _should_ be reported; we fall
556 back to SIGIO in that case. --sct */
557 si.si_signo = signum;
558 si.si_errno = 0;
559 si.si_code = reason;
560 /* Make sure we are called with one of the POLL_*
561 reasons, otherwise we could leak kernel stack into
562 userspace. */
563 BUG_ON((reason & __SI_MASK) != __SI_POLL);
564 if (reason - POLL_IN >= NSIGPOLL)
565 si.si_band = ~0L;
566 else
567 si.si_band = band_table[reason - POLL_IN];
568 si.si_fd = fd;
569 if (!do_send_sig_info(signum, &si, p, group))
570 break;
571 /* fall-through: fall back on the old plain SIGIO signal */
572 case 0:
573 do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
574 }
575}
576
577void send_sigio(struct fown_struct *fown, int fd, int band)
578{
579 struct task_struct *p;
580 enum pid_type type;
581 struct pid *pid;
582 int group = 1;
583
584 read_lock(&fown->lock);
585
586 type = fown->pid_type;
587 if (type == PIDTYPE_MAX) {
588 group = 0;
589 type = PIDTYPE_PID;
590 }
591
592 pid = fown->pid;
593 if (!pid)
594 goto out_unlock_fown;
595
596 read_lock(&tasklist_lock);
597 do_each_pid_task(pid, type, p) {
598 send_sigio_to_task(p, fown, fd, band, group);
599 } while_each_pid_task(pid, type, p);
600 read_unlock(&tasklist_lock);
601 out_unlock_fown:
602 read_unlock(&fown->lock);
603}
604
605static void send_sigurg_to_task(struct task_struct *p,
606 struct fown_struct *fown, int group)
607{
608 if (sigio_perm(p, fown, SIGURG))
609 do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
610}
611
612int send_sigurg(struct fown_struct *fown)
613{
614 struct task_struct *p;
615 enum pid_type type;
616 struct pid *pid;
617 int group = 1;
618 int ret = 0;
619
620 read_lock(&fown->lock);
621
622 type = fown->pid_type;
623 if (type == PIDTYPE_MAX) {
624 group = 0;
625 type = PIDTYPE_PID;
626 }
627
628 pid = fown->pid;
629 if (!pid)
630 goto out_unlock_fown;
631
632 ret = 1;
633
634 read_lock(&tasklist_lock);
635 do_each_pid_task(pid, type, p) {
636 send_sigurg_to_task(p, fown, group);
637 } while_each_pid_task(pid, type, p);
638 read_unlock(&tasklist_lock);
639 out_unlock_fown:
640 read_unlock(&fown->lock);
641 return ret;
642}
643
644static DEFINE_SPINLOCK(fasync_lock);
645static struct kmem_cache *fasync_cache __read_mostly;
646
647static void fasync_free_rcu(struct rcu_head *head)
648{
649 kmem_cache_free(fasync_cache,
650 container_of(head, struct fasync_struct, fa_rcu));
651}
652
653/*
654 * Remove a fasync entry. If successfully removed, return
655 * positive and clear the FASYNC flag. If no entry exists,
656 * do nothing and return 0.
657 *
658 * NOTE! It is very important that the FASYNC flag always
659 * match the state "is the filp on a fasync list".
660 *
661 */
662int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
663{
664 struct fasync_struct *fa, **fp;
665 int result = 0;
666
667 spin_lock(&filp->f_lock);
668 spin_lock(&fasync_lock);
669 for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
670 if (fa->fa_file != filp)
671 continue;
672
673 spin_lock_irq(&fa->fa_lock);
674 fa->fa_file = NULL;
675 spin_unlock_irq(&fa->fa_lock);
676
677 *fp = fa->fa_next;
678 call_rcu(&fa->fa_rcu, fasync_free_rcu);
679 filp->f_flags &= ~FASYNC;
680 result = 1;
681 break;
682 }
683 spin_unlock(&fasync_lock);
684 spin_unlock(&filp->f_lock);
685 return result;
686}
687
688struct fasync_struct *fasync_alloc(void)
689{
690 return kmem_cache_alloc(fasync_cache, GFP_KERNEL);
691}
692
693/*
694 * NOTE! This can be used only for unused fasync entries:
695 * entries that actually got inserted on the fasync list
696 * need to be released by rcu - see fasync_remove_entry.
697 */
698void fasync_free(struct fasync_struct *new)
699{
700 kmem_cache_free(fasync_cache, new);
701}
702
703/*
704 * Insert a new entry into the fasync list. Return the pointer to the
705 * old one if we didn't use the new one.
706 *
707 * NOTE! It is very important that the FASYNC flag always
708 * match the state "is the filp on a fasync list".
709 */
710struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)
711{
712 struct fasync_struct *fa, **fp;
713
714 spin_lock(&filp->f_lock);
715 spin_lock(&fasync_lock);
716 for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
717 if (fa->fa_file != filp)
718 continue;
719
720 spin_lock_irq(&fa->fa_lock);
721 fa->fa_fd = fd;
722 spin_unlock_irq(&fa->fa_lock);
723 goto out;
724 }
725
726 spin_lock_init(&new->fa_lock);
727 new->magic = FASYNC_MAGIC;
728 new->fa_file = filp;
729 new->fa_fd = fd;
730 new->fa_next = *fapp;
731 rcu_assign_pointer(*fapp, new);
732 filp->f_flags |= FASYNC;
733
734out:
735 spin_unlock(&fasync_lock);
736 spin_unlock(&filp->f_lock);
737 return fa;
738}
739
740/*
741 * Add a fasync entry. Return negative on error, positive if
742 * added, and zero if did nothing but change an existing one.
743 */
744static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
745{
746 struct fasync_struct *new;
747
748 new = fasync_alloc();
749 if (!new)
750 return -ENOMEM;
751
752 /*
753 * fasync_insert_entry() returns the old (update) entry if
754 * it existed.
755 *
756 * So free the (unused) new entry and return 0 to let the
757 * caller know that we didn't add any new fasync entries.
758 */
759 if (fasync_insert_entry(fd, filp, fapp, new)) {
760 fasync_free(new);
761 return 0;
762 }
763
764 return 1;
765}
766
767/*
768 * fasync_helper() is used by almost all character device drivers
769 * to set up the fasync queue, and for regular files by the file
770 * lease code. It returns negative on error, 0 if it did no changes
771 * and positive if it added/deleted the entry.
772 */
773int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
774{
775 if (!on)
776 return fasync_remove_entry(filp, fapp);
777 return fasync_add_entry(fd, filp, fapp);
778}
779
780EXPORT_SYMBOL(fasync_helper);
781
782/*
783 * rcu_read_lock() is held
784 */
785static void kill_fasync_rcu(struct fasync_struct *fa, int sig, int band)
786{
787 while (fa) {
788 struct fown_struct *fown;
789 unsigned long flags;
790
791 if (fa->magic != FASYNC_MAGIC) {
792 printk(KERN_ERR "kill_fasync: bad magic number in "
793 "fasync_struct!\n");
794 return;
795 }
796 spin_lock_irqsave(&fa->fa_lock, flags);
797 if (fa->fa_file) {
798 fown = &fa->fa_file->f_owner;
799 /* Don't send SIGURG to processes which have not set a
800 queued signum: SIGURG has its own default signalling
801 mechanism. */
802 if (!(sig == SIGURG && fown->signum == 0))
803 send_sigio(fown, fa->fa_fd, band);
804 }
805 spin_unlock_irqrestore(&fa->fa_lock, flags);
806 fa = rcu_dereference(fa->fa_next);
807 }
808}
809
810void kill_fasync(struct fasync_struct **fp, int sig, int band)
811{
812 /* First a quick test without locking: usually
813 * the list is empty.
814 */
815 if (*fp) {
816 rcu_read_lock();
817 kill_fasync_rcu(rcu_dereference(*fp), sig, band);
818 rcu_read_unlock();
819 }
820}
821EXPORT_SYMBOL(kill_fasync);
822
823static int __init fcntl_init(void)
824{
825 /*
826 * Please add new bits here to ensure allocation uniqueness.
827 * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
828 * is defined as O_NONBLOCK on some platforms and not on others.
829 */
830 BUILD_BUG_ON(19 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
831 O_RDONLY | O_WRONLY | O_RDWR |
832 O_CREAT | O_EXCL | O_NOCTTY |
833 O_TRUNC | O_APPEND | /* O_NONBLOCK | */
834 __O_SYNC | O_DSYNC | FASYNC |
835 O_DIRECT | O_LARGEFILE | O_DIRECTORY |
836 O_NOFOLLOW | O_NOATIME | O_CLOEXEC |
837 __FMODE_EXEC | O_PATH
838 ));
839
840 fasync_cache = kmem_cache_create("fasync_cache",
841 sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
842 return 0;
843}
844
845module_init(fcntl_init)