1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/fanotify.h>
3 #include <linux/fcntl.h>
4 #include <linux/file.h>
6 #include <linux/anon_inodes.h>
7 #include <linux/fsnotify_backend.h>
8 #include <linux/init.h>
9 #include <linux/mount.h>
10 #include <linux/namei.h>
11 #include <linux/poll.h>
12 #include <linux/security.h>
13 #include <linux/syscalls.h>
14 #include <linux/slab.h>
15 #include <linux/types.h>
16 #include <linux/uaccess.h>
17 #include <linux/compat.h>
18 #include <linux/sched/signal.h>
20 #include <asm/ioctls.h>
22 #include "../../mount.h"
23 #include "../fdinfo.h"
26 #define FANOTIFY_DEFAULT_MAX_EVENTS 16384
27 #define FANOTIFY_DEFAULT_MAX_MARKS 8192
28 #define FANOTIFY_DEFAULT_MAX_LISTENERS 128
31 * All flags that may be specified in parameter event_f_flags of fanotify_init.
33 * Internal and external open flags are stored together in field f_flags of
34 * struct file. Only external open flags shall be allowed in event_f_flags.
35 * Internal flags like FMODE_NONOTIFY, FMODE_EXEC, FMODE_NOCMTIME shall be
38 #define FANOTIFY_INIT_ALL_EVENT_F_BITS ( \
39 O_ACCMODE | O_APPEND | O_NONBLOCK | \
40 __O_SYNC | O_DSYNC | O_CLOEXEC | \
41 O_LARGEFILE | O_NOATIME )
43 extern const struct fsnotify_ops fanotify_fsnotify_ops
;
45 struct kmem_cache
*fanotify_mark_cache __read_mostly
;
46 struct kmem_cache
*fanotify_event_cachep __read_mostly
;
47 struct kmem_cache
*fanotify_perm_event_cachep __read_mostly
;
50 * Get an fsnotify notification event if one exists and is small
51 * enough to fit in "count". Return an error pointer if the count
52 * is not large enough.
54 * Called with the group->notification_lock held.
56 static struct fsnotify_event
*get_one_event(struct fsnotify_group
*group
,
59 assert_spin_locked(&group
->notification_lock
);
61 pr_debug("%s: group=%p count=%zd\n", __func__
, group
, count
);
63 if (fsnotify_notify_queue_is_empty(group
))
66 if (FAN_EVENT_METADATA_LEN
> count
)
67 return ERR_PTR(-EINVAL
);
69 /* held the notification_lock the whole time, so this is the
70 * same event we peeked above */
71 return fsnotify_remove_first_event(group
);
74 static int create_fd(struct fsnotify_group
*group
,
75 struct fanotify_event_info
*event
,
79 struct file
*new_file
;
81 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
83 client_fd
= get_unused_fd_flags(group
->fanotify_data
.f_flags
);
88 * we need a new file handle for the userspace program so it can read even if it was
89 * originally opened O_WRONLY.
91 /* it's possible this event was an overflow event. in that case dentry and mnt
92 * are NULL; That's fine, just don't call dentry open */
93 if (event
->path
.dentry
&& event
->path
.mnt
)
94 new_file
= dentry_open(&event
->path
,
95 group
->fanotify_data
.f_flags
| FMODE_NONOTIFY
,
98 new_file
= ERR_PTR(-EOVERFLOW
);
99 if (IS_ERR(new_file
)) {
101 * we still send an event even if we can't open the file. this
102 * can happen when say tasks are gone and we try to open their
103 * /proc files or we try to open a WRONLY file like in sysfs
104 * we just send the errno to userspace since there isn't much
107 put_unused_fd(client_fd
);
108 client_fd
= PTR_ERR(new_file
);
116 static int fill_event_metadata(struct fsnotify_group
*group
,
117 struct fanotify_event_metadata
*metadata
,
118 struct fsnotify_event
*fsn_event
,
122 struct fanotify_event_info
*event
;
124 pr_debug("%s: group=%p metadata=%p event=%p\n", __func__
,
125 group
, metadata
, fsn_event
);
128 event
= container_of(fsn_event
, struct fanotify_event_info
, fse
);
129 metadata
->event_len
= FAN_EVENT_METADATA_LEN
;
130 metadata
->metadata_len
= FAN_EVENT_METADATA_LEN
;
131 metadata
->vers
= FANOTIFY_METADATA_VERSION
;
132 metadata
->reserved
= 0;
133 metadata
->mask
= fsn_event
->mask
& FAN_ALL_OUTGOING_EVENTS
;
134 metadata
->pid
= pid_vnr(event
->tgid
);
135 if (unlikely(fsn_event
->mask
& FAN_Q_OVERFLOW
))
136 metadata
->fd
= FAN_NOFD
;
138 metadata
->fd
= create_fd(group
, event
, file
);
139 if (metadata
->fd
< 0)
146 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
147 static struct fanotify_perm_event_info
*dequeue_event(
148 struct fsnotify_group
*group
, int fd
)
150 struct fanotify_perm_event_info
*event
, *return_e
= NULL
;
152 spin_lock(&group
->notification_lock
);
153 list_for_each_entry(event
, &group
->fanotify_data
.access_list
,
158 list_del_init(&event
->fae
.fse
.list
);
162 spin_unlock(&group
->notification_lock
);
164 pr_debug("%s: found return_re=%p\n", __func__
, return_e
);
169 static int process_access_response(struct fsnotify_group
*group
,
170 struct fanotify_response
*response_struct
)
172 struct fanotify_perm_event_info
*event
;
173 int fd
= response_struct
->fd
;
174 int response
= response_struct
->response
;
176 pr_debug("%s: group=%p fd=%d response=%d\n", __func__
, group
,
179 * make sure the response is valid, if invalid we do nothing and either
180 * userspace can send a valid response or we will clean it up after the
194 event
= dequeue_event(group
, fd
);
198 event
->response
= response
;
199 wake_up(&group
->fanotify_data
.access_waitq
);
205 static ssize_t
copy_event_to_user(struct fsnotify_group
*group
,
206 struct fsnotify_event
*event
,
209 struct fanotify_event_metadata fanotify_event_metadata
;
213 pr_debug("%s: group=%p event=%p\n", __func__
, group
, event
);
215 ret
= fill_event_metadata(group
, &fanotify_event_metadata
, event
, &f
);
219 fd
= fanotify_event_metadata
.fd
;
221 if (copy_to_user(buf
, &fanotify_event_metadata
,
222 fanotify_event_metadata
.event_len
))
225 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
226 if (event
->mask
& FAN_ALL_PERM_EVENTS
)
227 FANOTIFY_PE(event
)->fd
= fd
;
232 return fanotify_event_metadata
.event_len
;
235 if (fd
!= FAN_NOFD
) {
242 /* intofiy userspace file descriptor functions */
243 static unsigned int fanotify_poll(struct file
*file
, poll_table
*wait
)
245 struct fsnotify_group
*group
= file
->private_data
;
248 poll_wait(file
, &group
->notification_waitq
, wait
);
249 spin_lock(&group
->notification_lock
);
250 if (!fsnotify_notify_queue_is_empty(group
))
251 ret
= POLLIN
| POLLRDNORM
;
252 spin_unlock(&group
->notification_lock
);
257 static ssize_t
fanotify_read(struct file
*file
, char __user
*buf
,
258 size_t count
, loff_t
*pos
)
260 struct fsnotify_group
*group
;
261 struct fsnotify_event
*kevent
;
264 DEFINE_WAIT_FUNC(wait
, woken_wake_function
);
267 group
= file
->private_data
;
269 pr_debug("%s: group=%p\n", __func__
, group
);
271 add_wait_queue(&group
->notification_waitq
, &wait
);
273 spin_lock(&group
->notification_lock
);
274 kevent
= get_one_event(group
, count
);
275 spin_unlock(&group
->notification_lock
);
277 if (IS_ERR(kevent
)) {
278 ret
= PTR_ERR(kevent
);
284 if (file
->f_flags
& O_NONBLOCK
)
288 if (signal_pending(current
))
294 wait_woken(&wait
, TASK_INTERRUPTIBLE
, MAX_SCHEDULE_TIMEOUT
);
298 ret
= copy_event_to_user(group
, kevent
, buf
);
299 if (unlikely(ret
== -EOPENSTALE
)) {
301 * We cannot report events with stale fd so drop it.
302 * Setting ret to 0 will continue the event loop and
303 * do the right thing if there are no more events to
304 * read (i.e. return bytes read, -EAGAIN or wait).
310 * Permission events get queued to wait for response. Other
311 * events can be destroyed now.
313 if (!(kevent
->mask
& FAN_ALL_PERM_EVENTS
)) {
314 fsnotify_destroy_event(group
, kevent
);
316 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
318 FANOTIFY_PE(kevent
)->response
= FAN_DENY
;
319 wake_up(&group
->fanotify_data
.access_waitq
);
321 spin_lock(&group
->notification_lock
);
322 list_add_tail(&kevent
->list
,
323 &group
->fanotify_data
.access_list
);
324 spin_unlock(&group
->notification_lock
);
333 remove_wait_queue(&group
->notification_waitq
, &wait
);
335 if (start
!= buf
&& ret
!= -EFAULT
)
340 static ssize_t
fanotify_write(struct file
*file
, const char __user
*buf
, size_t count
, loff_t
*pos
)
342 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
343 struct fanotify_response response
= { .fd
= -1, .response
= -1 };
344 struct fsnotify_group
*group
;
347 group
= file
->private_data
;
349 if (count
> sizeof(response
))
350 count
= sizeof(response
);
352 pr_debug("%s: group=%p count=%zu\n", __func__
, group
, count
);
354 if (copy_from_user(&response
, buf
, count
))
357 ret
= process_access_response(group
, &response
);
367 static int fanotify_release(struct inode
*ignored
, struct file
*file
)
369 struct fsnotify_group
*group
= file
->private_data
;
371 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
372 struct fanotify_perm_event_info
*event
, *next
;
373 struct fsnotify_event
*fsn_event
;
376 * Stop new events from arriving in the notification queue. since
377 * userspace cannot use fanotify fd anymore, no event can enter or
378 * leave access_list by now either.
380 fsnotify_group_stop_queueing(group
);
383 * Process all permission events on access_list and notification queue
384 * and simulate reply from userspace.
386 spin_lock(&group
->notification_lock
);
387 list_for_each_entry_safe(event
, next
, &group
->fanotify_data
.access_list
,
389 pr_debug("%s: found group=%p event=%p\n", __func__
, group
,
392 list_del_init(&event
->fae
.fse
.list
);
393 event
->response
= FAN_ALLOW
;
397 * Destroy all non-permission events. For permission events just
398 * dequeue them and set the response. They will be freed once the
399 * response is consumed and fanotify_get_response() returns.
401 while (!fsnotify_notify_queue_is_empty(group
)) {
402 fsn_event
= fsnotify_remove_first_event(group
);
403 if (!(fsn_event
->mask
& FAN_ALL_PERM_EVENTS
)) {
404 spin_unlock(&group
->notification_lock
);
405 fsnotify_destroy_event(group
, fsn_event
);
406 spin_lock(&group
->notification_lock
);
408 FANOTIFY_PE(fsn_event
)->response
= FAN_ALLOW
;
410 spin_unlock(&group
->notification_lock
);
412 /* Response for all permission events it set, wakeup waiters */
413 wake_up(&group
->fanotify_data
.access_waitq
);
416 /* matches the fanotify_init->fsnotify_alloc_group */
417 fsnotify_destroy_group(group
);
422 static long fanotify_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
424 struct fsnotify_group
*group
;
425 struct fsnotify_event
*fsn_event
;
430 group
= file
->private_data
;
432 p
= (void __user
*) arg
;
436 spin_lock(&group
->notification_lock
);
437 list_for_each_entry(fsn_event
, &group
->notification_list
, list
)
438 send_len
+= FAN_EVENT_METADATA_LEN
;
439 spin_unlock(&group
->notification_lock
);
440 ret
= put_user(send_len
, (int __user
*) p
);
447 static const struct file_operations fanotify_fops
= {
448 .show_fdinfo
= fanotify_show_fdinfo
,
449 .poll
= fanotify_poll
,
450 .read
= fanotify_read
,
451 .write
= fanotify_write
,
453 .release
= fanotify_release
,
454 .unlocked_ioctl
= fanotify_ioctl
,
455 .compat_ioctl
= fanotify_ioctl
,
456 .llseek
= noop_llseek
,
459 static int fanotify_find_path(int dfd
, const char __user
*filename
,
460 struct path
*path
, unsigned int flags
)
464 pr_debug("%s: dfd=%d filename=%p flags=%x\n", __func__
,
465 dfd
, filename
, flags
);
467 if (filename
== NULL
) {
468 struct fd f
= fdget(dfd
);
475 if ((flags
& FAN_MARK_ONLYDIR
) &&
476 !(S_ISDIR(file_inode(f
.file
)->i_mode
))) {
481 *path
= f
.file
->f_path
;
485 unsigned int lookup_flags
= 0;
487 if (!(flags
& FAN_MARK_DONT_FOLLOW
))
488 lookup_flags
|= LOOKUP_FOLLOW
;
489 if (flags
& FAN_MARK_ONLYDIR
)
490 lookup_flags
|= LOOKUP_DIRECTORY
;
492 ret
= user_path_at(dfd
, filename
, lookup_flags
, path
);
497 /* you can only watch an inode if you have read permissions on it */
498 ret
= inode_permission(path
->dentry
->d_inode
, MAY_READ
);
505 static __u32
fanotify_mark_remove_from_mask(struct fsnotify_mark
*fsn_mark
,
512 spin_lock(&fsn_mark
->lock
);
513 if (!(flags
& FAN_MARK_IGNORED_MASK
)) {
514 __u32 tmask
= fsn_mark
->mask
& ~mask
;
516 if (flags
& FAN_MARK_ONDIR
)
519 oldmask
= fsn_mark
->mask
;
520 fsn_mark
->mask
= tmask
;
522 __u32 tmask
= fsn_mark
->ignored_mask
& ~mask
;
523 if (flags
& FAN_MARK_ONDIR
)
525 fsn_mark
->ignored_mask
= tmask
;
527 *destroy
= !(fsn_mark
->mask
| fsn_mark
->ignored_mask
);
528 spin_unlock(&fsn_mark
->lock
);
530 return mask
& oldmask
;
533 static int fanotify_remove_vfsmount_mark(struct fsnotify_group
*group
,
534 struct vfsmount
*mnt
, __u32 mask
,
537 struct fsnotify_mark
*fsn_mark
= NULL
;
541 mutex_lock(&group
->mark_mutex
);
542 fsn_mark
= fsnotify_find_mark(&real_mount(mnt
)->mnt_fsnotify_marks
,
545 mutex_unlock(&group
->mark_mutex
);
549 removed
= fanotify_mark_remove_from_mask(fsn_mark
, mask
, flags
,
551 if (removed
& real_mount(mnt
)->mnt_fsnotify_mask
)
552 fsnotify_recalc_mask(real_mount(mnt
)->mnt_fsnotify_marks
);
554 fsnotify_detach_mark(fsn_mark
);
555 mutex_unlock(&group
->mark_mutex
);
557 fsnotify_free_mark(fsn_mark
);
559 fsnotify_put_mark(fsn_mark
);
563 static int fanotify_remove_inode_mark(struct fsnotify_group
*group
,
564 struct inode
*inode
, __u32 mask
,
567 struct fsnotify_mark
*fsn_mark
= NULL
;
571 mutex_lock(&group
->mark_mutex
);
572 fsn_mark
= fsnotify_find_mark(&inode
->i_fsnotify_marks
, group
);
574 mutex_unlock(&group
->mark_mutex
);
578 removed
= fanotify_mark_remove_from_mask(fsn_mark
, mask
, flags
,
580 if (removed
& inode
->i_fsnotify_mask
)
581 fsnotify_recalc_mask(inode
->i_fsnotify_marks
);
583 fsnotify_detach_mark(fsn_mark
);
584 mutex_unlock(&group
->mark_mutex
);
586 fsnotify_free_mark(fsn_mark
);
588 /* matches the fsnotify_find_mark() */
589 fsnotify_put_mark(fsn_mark
);
594 static __u32
fanotify_mark_add_to_mask(struct fsnotify_mark
*fsn_mark
,
600 spin_lock(&fsn_mark
->lock
);
601 if (!(flags
& FAN_MARK_IGNORED_MASK
)) {
602 __u32 tmask
= fsn_mark
->mask
| mask
;
604 if (flags
& FAN_MARK_ONDIR
)
607 oldmask
= fsn_mark
->mask
;
608 fsn_mark
->mask
= tmask
;
610 __u32 tmask
= fsn_mark
->ignored_mask
| mask
;
611 if (flags
& FAN_MARK_ONDIR
)
614 fsn_mark
->ignored_mask
= tmask
;
615 if (flags
& FAN_MARK_IGNORED_SURV_MODIFY
)
616 fsn_mark
->flags
|= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY
;
618 spin_unlock(&fsn_mark
->lock
);
620 return mask
& ~oldmask
;
623 static struct fsnotify_mark
*fanotify_add_new_mark(struct fsnotify_group
*group
,
625 struct vfsmount
*mnt
)
627 struct fsnotify_mark
*mark
;
630 if (atomic_read(&group
->num_marks
) > group
->fanotify_data
.max_marks
)
631 return ERR_PTR(-ENOSPC
);
633 mark
= kmem_cache_alloc(fanotify_mark_cache
, GFP_KERNEL
);
635 return ERR_PTR(-ENOMEM
);
637 fsnotify_init_mark(mark
, group
);
638 ret
= fsnotify_add_mark_locked(mark
, inode
, mnt
, 0);
640 fsnotify_put_mark(mark
);
648 static int fanotify_add_vfsmount_mark(struct fsnotify_group
*group
,
649 struct vfsmount
*mnt
, __u32 mask
,
652 struct fsnotify_mark
*fsn_mark
;
655 mutex_lock(&group
->mark_mutex
);
656 fsn_mark
= fsnotify_find_mark(&real_mount(mnt
)->mnt_fsnotify_marks
,
659 fsn_mark
= fanotify_add_new_mark(group
, NULL
, mnt
);
660 if (IS_ERR(fsn_mark
)) {
661 mutex_unlock(&group
->mark_mutex
);
662 return PTR_ERR(fsn_mark
);
665 added
= fanotify_mark_add_to_mask(fsn_mark
, mask
, flags
);
666 if (added
& ~real_mount(mnt
)->mnt_fsnotify_mask
)
667 fsnotify_recalc_mask(real_mount(mnt
)->mnt_fsnotify_marks
);
668 mutex_unlock(&group
->mark_mutex
);
670 fsnotify_put_mark(fsn_mark
);
674 static int fanotify_add_inode_mark(struct fsnotify_group
*group
,
675 struct inode
*inode
, __u32 mask
,
678 struct fsnotify_mark
*fsn_mark
;
681 pr_debug("%s: group=%p inode=%p\n", __func__
, group
, inode
);
684 * If some other task has this inode open for write we should not add
685 * an ignored mark, unless that ignored mark is supposed to survive
686 * modification changes anyway.
688 if ((flags
& FAN_MARK_IGNORED_MASK
) &&
689 !(flags
& FAN_MARK_IGNORED_SURV_MODIFY
) &&
690 (atomic_read(&inode
->i_writecount
) > 0))
693 mutex_lock(&group
->mark_mutex
);
694 fsn_mark
= fsnotify_find_mark(&inode
->i_fsnotify_marks
, group
);
696 fsn_mark
= fanotify_add_new_mark(group
, inode
, NULL
);
697 if (IS_ERR(fsn_mark
)) {
698 mutex_unlock(&group
->mark_mutex
);
699 return PTR_ERR(fsn_mark
);
702 added
= fanotify_mark_add_to_mask(fsn_mark
, mask
, flags
);
703 if (added
& ~inode
->i_fsnotify_mask
)
704 fsnotify_recalc_mask(inode
->i_fsnotify_marks
);
705 mutex_unlock(&group
->mark_mutex
);
707 fsnotify_put_mark(fsn_mark
);
711 /* fanotify syscalls */
712 SYSCALL_DEFINE2(fanotify_init
, unsigned int, flags
, unsigned int, event_f_flags
)
714 struct fsnotify_group
*group
;
716 struct user_struct
*user
;
717 struct fanotify_event_info
*oevent
;
719 pr_debug("%s: flags=%d event_f_flags=%d\n",
720 __func__
, flags
, event_f_flags
);
722 if (!capable(CAP_SYS_ADMIN
))
725 if (flags
& ~FAN_ALL_INIT_FLAGS
)
728 if (event_f_flags
& ~FANOTIFY_INIT_ALL_EVENT_F_BITS
)
731 switch (event_f_flags
& O_ACCMODE
) {
740 user
= get_current_user();
741 if (atomic_read(&user
->fanotify_listeners
) > FANOTIFY_DEFAULT_MAX_LISTENERS
) {
746 f_flags
= O_RDWR
| FMODE_NONOTIFY
;
747 if (flags
& FAN_CLOEXEC
)
748 f_flags
|= O_CLOEXEC
;
749 if (flags
& FAN_NONBLOCK
)
750 f_flags
|= O_NONBLOCK
;
752 /* fsnotify_alloc_group takes a ref. Dropped in fanotify_release */
753 group
= fsnotify_alloc_group(&fanotify_fsnotify_ops
);
756 return PTR_ERR(group
);
759 group
->fanotify_data
.user
= user
;
760 atomic_inc(&user
->fanotify_listeners
);
762 oevent
= fanotify_alloc_event(NULL
, FS_Q_OVERFLOW
, NULL
);
763 if (unlikely(!oevent
)) {
765 goto out_destroy_group
;
767 group
->overflow_event
= &oevent
->fse
;
769 if (force_o_largefile())
770 event_f_flags
|= O_LARGEFILE
;
771 group
->fanotify_data
.f_flags
= event_f_flags
;
772 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
773 init_waitqueue_head(&group
->fanotify_data
.access_waitq
);
774 INIT_LIST_HEAD(&group
->fanotify_data
.access_list
);
776 switch (flags
& FAN_ALL_CLASS_BITS
) {
777 case FAN_CLASS_NOTIF
:
778 group
->priority
= FS_PRIO_0
;
780 case FAN_CLASS_CONTENT
:
781 group
->priority
= FS_PRIO_1
;
783 case FAN_CLASS_PRE_CONTENT
:
784 group
->priority
= FS_PRIO_2
;
788 goto out_destroy_group
;
791 if (flags
& FAN_UNLIMITED_QUEUE
) {
793 if (!capable(CAP_SYS_ADMIN
))
794 goto out_destroy_group
;
795 group
->max_events
= UINT_MAX
;
797 group
->max_events
= FANOTIFY_DEFAULT_MAX_EVENTS
;
800 if (flags
& FAN_UNLIMITED_MARKS
) {
802 if (!capable(CAP_SYS_ADMIN
))
803 goto out_destroy_group
;
804 group
->fanotify_data
.max_marks
= UINT_MAX
;
806 group
->fanotify_data
.max_marks
= FANOTIFY_DEFAULT_MAX_MARKS
;
809 fd
= anon_inode_getfd("[fanotify]", &fanotify_fops
, group
, f_flags
);
811 goto out_destroy_group
;
816 fsnotify_destroy_group(group
);
820 SYSCALL_DEFINE5(fanotify_mark
, int, fanotify_fd
, unsigned int, flags
,
821 __u64
, mask
, int, dfd
,
822 const char __user
*, pathname
)
824 struct inode
*inode
= NULL
;
825 struct vfsmount
*mnt
= NULL
;
826 struct fsnotify_group
*group
;
831 pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
832 __func__
, fanotify_fd
, flags
, dfd
, pathname
, mask
);
834 /* we only use the lower 32 bits as of right now. */
835 if (mask
& ((__u64
)0xffffffff << 32))
838 if (flags
& ~FAN_ALL_MARK_FLAGS
)
840 switch (flags
& (FAN_MARK_ADD
| FAN_MARK_REMOVE
| FAN_MARK_FLUSH
)) {
841 case FAN_MARK_ADD
: /* fallthrough */
842 case FAN_MARK_REMOVE
:
847 if (flags
& ~(FAN_MARK_MOUNT
| FAN_MARK_FLUSH
))
854 if (mask
& FAN_ONDIR
) {
855 flags
|= FAN_MARK_ONDIR
;
859 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
860 if (mask
& ~(FAN_ALL_EVENTS
| FAN_ALL_PERM_EVENTS
| FAN_EVENT_ON_CHILD
))
862 if (mask
& ~(FAN_ALL_EVENTS
| FAN_EVENT_ON_CHILD
))
866 f
= fdget(fanotify_fd
);
867 if (unlikely(!f
.file
))
870 /* verify that this is indeed an fanotify instance */
872 if (unlikely(f
.file
->f_op
!= &fanotify_fops
))
874 group
= f
.file
->private_data
;
877 * group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not
878 * allowed to set permissions events.
881 if (mask
& FAN_ALL_PERM_EVENTS
&&
882 group
->priority
== FS_PRIO_0
)
885 if (flags
& FAN_MARK_FLUSH
) {
887 if (flags
& FAN_MARK_MOUNT
)
888 fsnotify_clear_vfsmount_marks_by_group(group
);
890 fsnotify_clear_inode_marks_by_group(group
);
894 ret
= fanotify_find_path(dfd
, pathname
, &path
, flags
);
898 /* inode held in place by reference to path; group by fget on fd */
899 if (!(flags
& FAN_MARK_MOUNT
))
900 inode
= path
.dentry
->d_inode
;
904 /* create/update an inode mark */
905 switch (flags
& (FAN_MARK_ADD
| FAN_MARK_REMOVE
)) {
907 if (flags
& FAN_MARK_MOUNT
)
908 ret
= fanotify_add_vfsmount_mark(group
, mnt
, mask
, flags
);
910 ret
= fanotify_add_inode_mark(group
, inode
, mask
, flags
);
912 case FAN_MARK_REMOVE
:
913 if (flags
& FAN_MARK_MOUNT
)
914 ret
= fanotify_remove_vfsmount_mark(group
, mnt
, mask
, flags
);
916 ret
= fanotify_remove_inode_mark(group
, inode
, mask
, flags
);
929 COMPAT_SYSCALL_DEFINE6(fanotify_mark
,
930 int, fanotify_fd
, unsigned int, flags
,
931 __u32
, mask0
, __u32
, mask1
, int, dfd
,
932 const char __user
*, pathname
)
934 return sys_fanotify_mark(fanotify_fd
, flags
,
936 ((__u64
)mask0
<< 32) | mask1
,
938 ((__u64
)mask1
<< 32) | mask0
,
945 * fanotify_user_setup - Our initialization function. Note that we cannot return
946 * error because we have compiled-in VFS hooks. So an (unlikely) failure here
947 * must result in panic().
949 static int __init
fanotify_user_setup(void)
951 fanotify_mark_cache
= KMEM_CACHE(fsnotify_mark
, SLAB_PANIC
);
952 fanotify_event_cachep
= KMEM_CACHE(fanotify_event_info
, SLAB_PANIC
);
953 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
954 fanotify_perm_event_cachep
= KMEM_CACHE(fanotify_perm_event_info
,
960 device_initcall(fanotify_user_setup
);