1 // SPDX-License-Identifier: GPL-2.0
5 * Copyright (C) 1991, 1992 Linus Torvalds
8 #include <linux/syscalls.h>
9 #include <linux/init.h>
11 #include <linux/sched/task.h>
13 #include <linux/filelock.h>
14 #include <linux/file.h>
15 #include <linux/fdtable.h>
16 #include <linux/capability.h>
17 #include <linux/dnotify.h>
18 #include <linux/slab.h>
19 #include <linux/module.h>
20 #include <linux/pipe_fs_i.h>
21 #include <linux/security.h>
22 #include <linux/ptrace.h>
23 #include <linux/signal.h>
24 #include <linux/rcupdate.h>
25 #include <linux/pid_namespace.h>
26 #include <linux/user_namespace.h>
27 #include <linux/memfd.h>
28 #include <linux/compat.h>
29 #include <linux/mount.h>
31 #include <linux/poll.h>
32 #include <asm/siginfo.h>
33 #include <linux/uaccess.h>
35 #define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
37 static int setfl(int fd
, struct file
* filp
, unsigned int arg
)
39 struct inode
* inode
= file_inode(filp
);
43 * O_APPEND cannot be cleared if the file is marked as append-only
44 * and the file is open for write.
46 if (((arg
^ filp
->f_flags
) & O_APPEND
) && IS_APPEND(inode
))
49 /* O_NOATIME can only be set by the owner or superuser */
50 if ((arg
& O_NOATIME
) && !(filp
->f_flags
& O_NOATIME
))
51 if (!inode_owner_or_capable(file_mnt_idmap(filp
), inode
))
54 /* required for strict SunOS emulation */
55 if (O_NONBLOCK
!= O_NDELAY
)
59 /* Pipe packetized mode is controlled by O_DIRECT flag */
60 if (!S_ISFIFO(inode
->i_mode
) &&
62 !(filp
->f_mode
& FMODE_CAN_ODIRECT
))
65 if (filp
->f_op
->check_flags
)
66 error
= filp
->f_op
->check_flags(arg
);
71 * ->fasync() is responsible for setting the FASYNC bit.
73 if (((arg
^ filp
->f_flags
) & FASYNC
) && filp
->f_op
->fasync
) {
74 error
= filp
->f_op
->fasync(fd
, filp
, (arg
& FASYNC
) != 0);
80 spin_lock(&filp
->f_lock
);
81 filp
->f_flags
= (arg
& SETFL_MASK
) | (filp
->f_flags
& ~SETFL_MASK
);
82 filp
->f_iocb_flags
= iocb_flags(filp
);
83 spin_unlock(&filp
->f_lock
);
89 static void f_modown(struct file
*filp
, struct pid
*pid
, enum pid_type type
,
92 write_lock_irq(&filp
->f_owner
.lock
);
93 if (force
|| !filp
->f_owner
.pid
) {
94 put_pid(filp
->f_owner
.pid
);
95 filp
->f_owner
.pid
= get_pid(pid
);
96 filp
->f_owner
.pid_type
= type
;
99 const struct cred
*cred
= current_cred();
100 filp
->f_owner
.uid
= cred
->uid
;
101 filp
->f_owner
.euid
= cred
->euid
;
104 write_unlock_irq(&filp
->f_owner
.lock
);
107 void __f_setown(struct file
*filp
, struct pid
*pid
, enum pid_type type
,
110 security_file_set_fowner(filp
);
111 f_modown(filp
, pid
, type
, force
);
113 EXPORT_SYMBOL(__f_setown
);
115 int f_setown(struct file
*filp
, int who
, int force
)
118 struct pid
*pid
= NULL
;
123 /* avoid overflow below */
133 pid
= find_vpid(who
);
139 __f_setown(filp
, pid
, type
, force
);
144 EXPORT_SYMBOL(f_setown
);
146 void f_delown(struct file
*filp
)
148 f_modown(filp
, NULL
, PIDTYPE_TGID
, 1);
151 pid_t
f_getown(struct file
*filp
)
155 read_lock_irq(&filp
->f_owner
.lock
);
157 if (pid_task(filp
->f_owner
.pid
, filp
->f_owner
.pid_type
)) {
158 pid
= pid_vnr(filp
->f_owner
.pid
);
159 if (filp
->f_owner
.pid_type
== PIDTYPE_PGID
)
163 read_unlock_irq(&filp
->f_owner
.lock
);
167 static int f_setown_ex(struct file
*filp
, unsigned long arg
)
169 struct f_owner_ex __user
*owner_p
= (void __user
*)arg
;
170 struct f_owner_ex owner
;
175 ret
= copy_from_user(&owner
, owner_p
, sizeof(owner
));
179 switch (owner
.type
) {
197 pid
= find_vpid(owner
.pid
);
198 if (owner
.pid
&& !pid
)
201 __f_setown(filp
, pid
, type
, 1);
207 static int f_getown_ex(struct file
*filp
, unsigned long arg
)
209 struct f_owner_ex __user
*owner_p
= (void __user
*)arg
;
210 struct f_owner_ex owner
= {};
213 read_lock_irq(&filp
->f_owner
.lock
);
215 if (pid_task(filp
->f_owner
.pid
, filp
->f_owner
.pid_type
))
216 owner
.pid
= pid_vnr(filp
->f_owner
.pid
);
218 switch (filp
->f_owner
.pid_type
) {
220 owner
.type
= F_OWNER_TID
;
224 owner
.type
= F_OWNER_PID
;
228 owner
.type
= F_OWNER_PGRP
;
236 read_unlock_irq(&filp
->f_owner
.lock
);
239 ret
= copy_to_user(owner_p
, &owner
, sizeof(owner
));
246 #ifdef CONFIG_CHECKPOINT_RESTORE
247 static int f_getowner_uids(struct file
*filp
, unsigned long arg
)
249 struct user_namespace
*user_ns
= current_user_ns();
250 uid_t __user
*dst
= (void __user
*)arg
;
254 read_lock_irq(&filp
->f_owner
.lock
);
255 src
[0] = from_kuid(user_ns
, filp
->f_owner
.uid
);
256 src
[1] = from_kuid(user_ns
, filp
->f_owner
.euid
);
257 read_unlock_irq(&filp
->f_owner
.lock
);
259 err
= put_user(src
[0], &dst
[0]);
260 err
|= put_user(src
[1], &dst
[1]);
265 static int f_getowner_uids(struct file
*filp
, unsigned long arg
)
271 static bool rw_hint_valid(enum rw_hint hint
)
274 case RWH_WRITE_LIFE_NOT_SET
:
275 case RWH_WRITE_LIFE_NONE
:
276 case RWH_WRITE_LIFE_SHORT
:
277 case RWH_WRITE_LIFE_MEDIUM
:
278 case RWH_WRITE_LIFE_LONG
:
279 case RWH_WRITE_LIFE_EXTREME
:
286 static long fcntl_rw_hint(struct file
*file
, unsigned int cmd
,
289 struct inode
*inode
= file_inode(file
);
290 u64 __user
*argp
= (u64 __user
*)arg
;
296 h
= inode
->i_write_hint
;
297 if (copy_to_user(argp
, &h
, sizeof(*argp
)))
301 if (copy_from_user(&h
, argp
, sizeof(h
)))
303 hint
= (enum rw_hint
) h
;
304 if (!rw_hint_valid(hint
))
308 inode
->i_write_hint
= hint
;
316 static long do_fcntl(int fd
, unsigned int cmd
, unsigned long arg
,
319 void __user
*argp
= (void __user
*)arg
;
326 err
= f_dupfd(argi
, filp
, 0);
328 case F_DUPFD_CLOEXEC
:
329 err
= f_dupfd(argi
, filp
, O_CLOEXEC
);
332 err
= get_close_on_exec(fd
) ? FD_CLOEXEC
: 0;
336 set_close_on_exec(fd
, argi
& FD_CLOEXEC
);
342 err
= setfl(fd
, filp
, argi
);
344 #if BITS_PER_LONG != 32
345 /* 32-bit arches must use fcntl64() */
349 if (copy_from_user(&flock
, argp
, sizeof(flock
)))
351 err
= fcntl_getlk(filp
, cmd
, &flock
);
352 if (!err
&& copy_to_user(argp
, &flock
, sizeof(flock
)))
355 #if BITS_PER_LONG != 32
356 /* 32-bit arches must use fcntl64() */
363 if (copy_from_user(&flock
, argp
, sizeof(flock
)))
365 err
= fcntl_setlk(fd
, filp
, cmd
, &flock
);
369 * XXX If f_owner is a process group, the
370 * negative return value will get converted
371 * into an error. Oops. If we keep the
372 * current syscall conventions, the only way
373 * to fix this will be in libc.
375 err
= f_getown(filp
);
376 force_successful_syscall_return();
379 err
= f_setown(filp
, argi
, 1);
382 err
= f_getown_ex(filp
, arg
);
385 err
= f_setown_ex(filp
, arg
);
387 case F_GETOWNER_UIDS
:
388 err
= f_getowner_uids(filp
, arg
);
391 err
= filp
->f_owner
.signum
;
394 /* arg == 0 restores default behaviour. */
395 if (!valid_signal(argi
)) {
399 filp
->f_owner
.signum
= argi
;
402 err
= fcntl_getlease(filp
);
405 err
= fcntl_setlease(fd
, filp
, argi
);
408 err
= fcntl_dirnotify(fd
, filp
, argi
);
412 err
= pipe_fcntl(filp
, cmd
, argi
);
416 err
= memfd_fcntl(filp
, cmd
, argi
);
420 err
= fcntl_rw_hint(filp
, cmd
, arg
);
428 static int check_fcntl_cmd(unsigned cmd
)
432 case F_DUPFD_CLOEXEC
:
441 SYSCALL_DEFINE3(fcntl
, unsigned int, fd
, unsigned int, cmd
, unsigned long, arg
)
443 struct fd f
= fdget_raw(fd
);
449 if (unlikely(f
.file
->f_mode
& FMODE_PATH
)) {
450 if (!check_fcntl_cmd(cmd
))
454 err
= security_file_fcntl(f
.file
, cmd
, arg
);
456 err
= do_fcntl(fd
, cmd
, arg
, f
.file
);
464 #if BITS_PER_LONG == 32
465 SYSCALL_DEFINE3(fcntl64
, unsigned int, fd
, unsigned int, cmd
,
468 void __user
*argp
= (void __user
*)arg
;
469 struct fd f
= fdget_raw(fd
);
470 struct flock64 flock
;
476 if (unlikely(f
.file
->f_mode
& FMODE_PATH
)) {
477 if (!check_fcntl_cmd(cmd
))
481 err
= security_file_fcntl(f
.file
, cmd
, arg
);
489 if (copy_from_user(&flock
, argp
, sizeof(flock
)))
491 err
= fcntl_getlk64(f
.file
, cmd
, &flock
);
492 if (!err
&& copy_to_user(argp
, &flock
, sizeof(flock
)))
500 if (copy_from_user(&flock
, argp
, sizeof(flock
)))
502 err
= fcntl_setlk64(fd
, f
.file
, cmd
, &flock
);
505 err
= do_fcntl(fd
, cmd
, arg
, f
.file
);
516 /* careful - don't use anywhere else */
517 #define copy_flock_fields(dst, src) \
518 (dst)->l_type = (src)->l_type; \
519 (dst)->l_whence = (src)->l_whence; \
520 (dst)->l_start = (src)->l_start; \
521 (dst)->l_len = (src)->l_len; \
522 (dst)->l_pid = (src)->l_pid;
524 static int get_compat_flock(struct flock
*kfl
, const struct compat_flock __user
*ufl
)
526 struct compat_flock fl
;
528 if (copy_from_user(&fl
, ufl
, sizeof(struct compat_flock
)))
530 copy_flock_fields(kfl
, &fl
);
534 static int get_compat_flock64(struct flock
*kfl
, const struct compat_flock64 __user
*ufl
)
536 struct compat_flock64 fl
;
538 if (copy_from_user(&fl
, ufl
, sizeof(struct compat_flock64
)))
540 copy_flock_fields(kfl
, &fl
);
544 static int put_compat_flock(const struct flock
*kfl
, struct compat_flock __user
*ufl
)
546 struct compat_flock fl
;
548 memset(&fl
, 0, sizeof(struct compat_flock
));
549 copy_flock_fields(&fl
, kfl
);
550 if (copy_to_user(ufl
, &fl
, sizeof(struct compat_flock
)))
555 static int put_compat_flock64(const struct flock
*kfl
, struct compat_flock64 __user
*ufl
)
557 struct compat_flock64 fl
;
559 BUILD_BUG_ON(sizeof(kfl
->l_start
) > sizeof(ufl
->l_start
));
560 BUILD_BUG_ON(sizeof(kfl
->l_len
) > sizeof(ufl
->l_len
));
562 memset(&fl
, 0, sizeof(struct compat_flock64
));
563 copy_flock_fields(&fl
, kfl
);
564 if (copy_to_user(ufl
, &fl
, sizeof(struct compat_flock64
)))
568 #undef copy_flock_fields
571 convert_fcntl_cmd(unsigned int cmd
)
586 * GETLK was successful and we need to return the data, but it needs to fit in
587 * the compat structure.
588 * l_start shouldn't be too big, unless the original start + end is greater than
589 * COMPAT_OFF_T_MAX, in which case the app was asking for trouble, so we return
590 * -EOVERFLOW in that case. l_len could be too big, in which case we just
591 * truncate it, and only allow the app to see that part of the conflicting lock
592 * that might make sense to it anyway
594 static int fixup_compat_flock(struct flock
*flock
)
596 if (flock
->l_start
> COMPAT_OFF_T_MAX
)
598 if (flock
->l_len
> COMPAT_OFF_T_MAX
)
599 flock
->l_len
= COMPAT_OFF_T_MAX
;
603 static long do_compat_fcntl64(unsigned int fd
, unsigned int cmd
,
606 struct fd f
= fdget_raw(fd
);
613 if (unlikely(f
.file
->f_mode
& FMODE_PATH
)) {
614 if (!check_fcntl_cmd(cmd
))
618 err
= security_file_fcntl(f
.file
, cmd
, arg
);
624 err
= get_compat_flock(&flock
, compat_ptr(arg
));
627 err
= fcntl_getlk(f
.file
, convert_fcntl_cmd(cmd
), &flock
);
630 err
= fixup_compat_flock(&flock
);
632 err
= put_compat_flock(&flock
, compat_ptr(arg
));
636 err
= get_compat_flock64(&flock
, compat_ptr(arg
));
639 err
= fcntl_getlk(f
.file
, convert_fcntl_cmd(cmd
), &flock
);
641 err
= put_compat_flock64(&flock
, compat_ptr(arg
));
645 err
= get_compat_flock(&flock
, compat_ptr(arg
));
648 err
= fcntl_setlk(fd
, f
.file
, convert_fcntl_cmd(cmd
), &flock
);
654 err
= get_compat_flock64(&flock
, compat_ptr(arg
));
657 err
= fcntl_setlk(fd
, f
.file
, convert_fcntl_cmd(cmd
), &flock
);
660 err
= do_fcntl(fd
, cmd
, arg
, f
.file
);
668 COMPAT_SYSCALL_DEFINE3(fcntl64
, unsigned int, fd
, unsigned int, cmd
,
671 return do_compat_fcntl64(fd
, cmd
, arg
);
674 COMPAT_SYSCALL_DEFINE3(fcntl
, unsigned int, fd
, unsigned int, cmd
,
686 return do_compat_fcntl64(fd
, cmd
, arg
);
690 /* Table to convert sigio signal codes into poll band bitmaps */
692 static const __poll_t band_table
[NSIGPOLL
] = {
693 EPOLLIN
| EPOLLRDNORM
, /* POLL_IN */
694 EPOLLOUT
| EPOLLWRNORM
| EPOLLWRBAND
, /* POLL_OUT */
695 EPOLLIN
| EPOLLRDNORM
| EPOLLMSG
, /* POLL_MSG */
696 EPOLLERR
, /* POLL_ERR */
697 EPOLLPRI
| EPOLLRDBAND
, /* POLL_PRI */
698 EPOLLHUP
| EPOLLERR
/* POLL_HUP */
701 static inline int sigio_perm(struct task_struct
*p
,
702 struct fown_struct
*fown
, int sig
)
704 const struct cred
*cred
;
708 cred
= __task_cred(p
);
709 ret
= ((uid_eq(fown
->euid
, GLOBAL_ROOT_UID
) ||
710 uid_eq(fown
->euid
, cred
->suid
) || uid_eq(fown
->euid
, cred
->uid
) ||
711 uid_eq(fown
->uid
, cred
->suid
) || uid_eq(fown
->uid
, cred
->uid
)) &&
712 !security_file_send_sigiotask(p
, fown
, sig
));
717 static void send_sigio_to_task(struct task_struct
*p
,
718 struct fown_struct
*fown
,
719 int fd
, int reason
, enum pid_type type
)
722 * F_SETSIG can change ->signum lockless in parallel, make
723 * sure we read it once and use the same value throughout.
725 int signum
= READ_ONCE(fown
->signum
);
727 if (!sigio_perm(p
, fown
, signum
))
734 /* Queue a rt signal with the appropriate fd as its
735 value. We use SI_SIGIO as the source, not
736 SI_KERNEL, since kernel signals always get
737 delivered even if we can't queue. Failure to
738 queue in this case _should_ be reported; we fall
739 back to SIGIO in that case. --sct */
741 si
.si_signo
= signum
;
745 * Posix definies POLL_IN and friends to be signal
746 * specific si_codes for SIG_POLL. Linux extended
747 * these si_codes to other signals in a way that is
748 * ambiguous if other signals also have signal
749 * specific si_codes. In that case use SI_SIGIO instead
750 * to remove the ambiguity.
752 if ((signum
!= SIGPOLL
) && sig_specific_sicodes(signum
))
753 si
.si_code
= SI_SIGIO
;
755 /* Make sure we are called with one of the POLL_*
756 reasons, otherwise we could leak kernel stack into
758 BUG_ON((reason
< POLL_IN
) || ((reason
- POLL_IN
) >= NSIGPOLL
));
759 if (reason
- POLL_IN
>= NSIGPOLL
)
762 si
.si_band
= mangle_poll(band_table
[reason
- POLL_IN
]);
764 if (!do_send_sig_info(signum
, &si
, p
, type
))
767 fallthrough
; /* fall back on the old plain SIGIO signal */
769 do_send_sig_info(SIGIO
, SEND_SIG_PRIV
, p
, type
);
773 void send_sigio(struct fown_struct
*fown
, int fd
, int band
)
775 struct task_struct
*p
;
780 read_lock_irqsave(&fown
->lock
, flags
);
782 type
= fown
->pid_type
;
785 goto out_unlock_fown
;
787 if (type
<= PIDTYPE_TGID
) {
789 p
= pid_task(pid
, PIDTYPE_PID
);
791 send_sigio_to_task(p
, fown
, fd
, band
, type
);
794 read_lock(&tasklist_lock
);
795 do_each_pid_task(pid
, type
, p
) {
796 send_sigio_to_task(p
, fown
, fd
, band
, type
);
797 } while_each_pid_task(pid
, type
, p
);
798 read_unlock(&tasklist_lock
);
801 read_unlock_irqrestore(&fown
->lock
, flags
);
804 static void send_sigurg_to_task(struct task_struct
*p
,
805 struct fown_struct
*fown
, enum pid_type type
)
807 if (sigio_perm(p
, fown
, SIGURG
))
808 do_send_sig_info(SIGURG
, SEND_SIG_PRIV
, p
, type
);
811 int send_sigurg(struct fown_struct
*fown
)
813 struct task_struct
*p
;
819 read_lock_irqsave(&fown
->lock
, flags
);
821 type
= fown
->pid_type
;
824 goto out_unlock_fown
;
828 if (type
<= PIDTYPE_TGID
) {
830 p
= pid_task(pid
, PIDTYPE_PID
);
832 send_sigurg_to_task(p
, fown
, type
);
835 read_lock(&tasklist_lock
);
836 do_each_pid_task(pid
, type
, p
) {
837 send_sigurg_to_task(p
, fown
, type
);
838 } while_each_pid_task(pid
, type
, p
);
839 read_unlock(&tasklist_lock
);
842 read_unlock_irqrestore(&fown
->lock
, flags
);
846 static DEFINE_SPINLOCK(fasync_lock
);
847 static struct kmem_cache
*fasync_cache __ro_after_init
;
849 static void fasync_free_rcu(struct rcu_head
*head
)
851 kmem_cache_free(fasync_cache
,
852 container_of(head
, struct fasync_struct
, fa_rcu
));
856 * Remove a fasync entry. If successfully removed, return
857 * positive and clear the FASYNC flag. If no entry exists,
858 * do nothing and return 0.
860 * NOTE! It is very important that the FASYNC flag always
861 * match the state "is the filp on a fasync list".
864 int fasync_remove_entry(struct file
*filp
, struct fasync_struct
**fapp
)
866 struct fasync_struct
*fa
, **fp
;
869 spin_lock(&filp
->f_lock
);
870 spin_lock(&fasync_lock
);
871 for (fp
= fapp
; (fa
= *fp
) != NULL
; fp
= &fa
->fa_next
) {
872 if (fa
->fa_file
!= filp
)
875 write_lock_irq(&fa
->fa_lock
);
877 write_unlock_irq(&fa
->fa_lock
);
880 call_rcu(&fa
->fa_rcu
, fasync_free_rcu
);
881 filp
->f_flags
&= ~FASYNC
;
885 spin_unlock(&fasync_lock
);
886 spin_unlock(&filp
->f_lock
);
890 struct fasync_struct
*fasync_alloc(void)
892 return kmem_cache_alloc(fasync_cache
, GFP_KERNEL
);
896 * NOTE! This can be used only for unused fasync entries:
897 * entries that actually got inserted on the fasync list
898 * need to be released by rcu - see fasync_remove_entry.
900 void fasync_free(struct fasync_struct
*new)
902 kmem_cache_free(fasync_cache
, new);
906 * Insert a new entry into the fasync list. Return the pointer to the
907 * old one if we didn't use the new one.
909 * NOTE! It is very important that the FASYNC flag always
910 * match the state "is the filp on a fasync list".
912 struct fasync_struct
*fasync_insert_entry(int fd
, struct file
*filp
, struct fasync_struct
**fapp
, struct fasync_struct
*new)
914 struct fasync_struct
*fa
, **fp
;
916 spin_lock(&filp
->f_lock
);
917 spin_lock(&fasync_lock
);
918 for (fp
= fapp
; (fa
= *fp
) != NULL
; fp
= &fa
->fa_next
) {
919 if (fa
->fa_file
!= filp
)
922 write_lock_irq(&fa
->fa_lock
);
924 write_unlock_irq(&fa
->fa_lock
);
928 rwlock_init(&new->fa_lock
);
929 new->magic
= FASYNC_MAGIC
;
932 new->fa_next
= *fapp
;
933 rcu_assign_pointer(*fapp
, new);
934 filp
->f_flags
|= FASYNC
;
937 spin_unlock(&fasync_lock
);
938 spin_unlock(&filp
->f_lock
);
943 * Add a fasync entry. Return negative on error, positive if
944 * added, and zero if did nothing but change an existing one.
946 static int fasync_add_entry(int fd
, struct file
*filp
, struct fasync_struct
**fapp
)
948 struct fasync_struct
*new;
950 new = fasync_alloc();
955 * fasync_insert_entry() returns the old (update) entry if
958 * So free the (unused) new entry and return 0 to let the
959 * caller know that we didn't add any new fasync entries.
961 if (fasync_insert_entry(fd
, filp
, fapp
, new)) {
970 * fasync_helper() is used by almost all character device drivers
971 * to set up the fasync queue, and for regular files by the file
972 * lease code. It returns negative on error, 0 if it did no changes
973 * and positive if it added/deleted the entry.
975 int fasync_helper(int fd
, struct file
* filp
, int on
, struct fasync_struct
**fapp
)
978 return fasync_remove_entry(filp
, fapp
);
979 return fasync_add_entry(fd
, filp
, fapp
);
982 EXPORT_SYMBOL(fasync_helper
);
985 * rcu_read_lock() is held
987 static void kill_fasync_rcu(struct fasync_struct
*fa
, int sig
, int band
)
990 struct fown_struct
*fown
;
993 if (fa
->magic
!= FASYNC_MAGIC
) {
994 printk(KERN_ERR
"kill_fasync: bad magic number in "
998 read_lock_irqsave(&fa
->fa_lock
, flags
);
1000 fown
= &fa
->fa_file
->f_owner
;
1001 /* Don't send SIGURG to processes which have not set a
1002 queued signum: SIGURG has its own default signalling
1004 if (!(sig
== SIGURG
&& fown
->signum
== 0))
1005 send_sigio(fown
, fa
->fa_fd
, band
);
1007 read_unlock_irqrestore(&fa
->fa_lock
, flags
);
1008 fa
= rcu_dereference(fa
->fa_next
);
1012 void kill_fasync(struct fasync_struct
**fp
, int sig
, int band
)
1014 /* First a quick test without locking: usually
1015 * the list is empty.
1019 kill_fasync_rcu(rcu_dereference(*fp
), sig
, band
);
1023 EXPORT_SYMBOL(kill_fasync
);
1025 static int __init
fcntl_init(void)
1028 * Please add new bits here to ensure allocation uniqueness.
1029 * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
1030 * is defined as O_NONBLOCK on some platforms and not on others.
1032 BUILD_BUG_ON(21 - 1 /* for O_RDONLY being 0 */ !=
1034 (VALID_OPEN_FLAGS
& ~(O_NONBLOCK
| O_NDELAY
)) |
1035 __FMODE_EXEC
| __FMODE_NONOTIFY
));
1037 fasync_cache
= kmem_cache_create("fasync_cache",
1038 sizeof(struct fasync_struct
), 0,
1039 SLAB_PANIC
| SLAB_ACCOUNT
, NULL
);
1043 module_init(fcntl_init
)