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TOMOYO Linux Cross Reference
Linux/fs/fcntl.c

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

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