]> bbs.cooldavid.org Git - net-next-2.6.git/blobdiff - fs/notify/fanotify/fanotify_user.c
fanotify: userspace interface for permission responses
[net-next-2.6.git] / fs / notify / fanotify / fanotify_user.c
index 67c0b5e4a4886b4838a6b026bf955c343bd3e49e..87f0be852f712b492eaca75ee6a18994d1bb6991 100644 (file)
+#include <linux/fanotify.h>
 #include <linux/fcntl.h>
+#include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/anon_inodes.h>
 #include <linux/fsnotify_backend.h>
+#include <linux/init.h>
+#include <linux/mount.h>
+#include <linux/namei.h>
+#include <linux/poll.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
 
-#include "fanotify.h"
+#include <asm/ioctls.h>
+
+extern const struct fsnotify_ops fanotify_fsnotify_ops;
+
+static struct kmem_cache *fanotify_mark_cache __read_mostly;
+static struct kmem_cache *fanotify_response_event_cache __read_mostly;
+
+struct fanotify_response_event {
+       struct list_head list;
+       __s32 fd;
+       struct fsnotify_event *event;
+};
+
+/*
+ * Get an fsnotify notification event if one exists and is small
+ * enough to fit in "count". Return an error pointer if the count
+ * is not large enough.
+ *
+ * Called with the group->notification_mutex held.
+ */
+static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
+                                           size_t count)
+{
+       BUG_ON(!mutex_is_locked(&group->notification_mutex));
+
+       pr_debug("%s: group=%p count=%zd\n", __func__, group, count);
+
+       if (fsnotify_notify_queue_is_empty(group))
+               return NULL;
+
+       if (FAN_EVENT_METADATA_LEN > count)
+               return ERR_PTR(-EINVAL);
+
+       /* held the notification_mutex the whole time, so this is the
+        * same event we peeked above */
+       return fsnotify_remove_notify_event(group);
+}
+
+static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
+{
+       int client_fd;
+       struct dentry *dentry;
+       struct vfsmount *mnt;
+       struct file *new_file;
+
+       pr_debug("%s: group=%p event=%p\n", __func__, group, event);
+
+       client_fd = get_unused_fd();
+       if (client_fd < 0)
+               return client_fd;
+
+       if (event->data_type != FSNOTIFY_EVENT_PATH) {
+               WARN_ON(1);
+               put_unused_fd(client_fd);
+               return -EINVAL;
+       }
+
+       /*
+        * we need a new file handle for the userspace program so it can read even if it was
+        * originally opened O_WRONLY.
+        */
+       dentry = dget(event->path.dentry);
+       mnt = mntget(event->path.mnt);
+       /* it's possible this event was an overflow event.  in that case dentry and mnt
+        * are NULL;  That's fine, just don't call dentry open */
+       if (dentry && mnt)
+               new_file = dentry_open(dentry, mnt,
+                                      O_RDONLY | O_LARGEFILE | FMODE_NONOTIFY,
+                                      current_cred());
+       else
+               new_file = ERR_PTR(-EOVERFLOW);
+       if (IS_ERR(new_file)) {
+               /*
+                * we still send an event even if we can't open the file.  this
+                * can happen when say tasks are gone and we try to open their
+                * /proc files or we try to open a WRONLY file like in sysfs
+                * we just send the errno to userspace since there isn't much
+                * else we can do.
+                */
+               put_unused_fd(client_fd);
+               client_fd = PTR_ERR(new_file);
+       } else {
+               fd_install(client_fd, new_file);
+       }
+
+       return client_fd;
+}
+
+static ssize_t fill_event_metadata(struct fsnotify_group *group,
+                                  struct fanotify_event_metadata *metadata,
+                                  struct fsnotify_event *event)
+{
+       pr_debug("%s: group=%p metadata=%p event=%p\n", __func__,
+                group, metadata, event);
+
+       metadata->event_len = FAN_EVENT_METADATA_LEN;
+       metadata->vers = FANOTIFY_METADATA_VERSION;
+       metadata->mask = event->mask & FAN_ALL_OUTGOING_EVENTS;
+       metadata->pid = pid_vnr(event->tgid);
+       metadata->fd = create_fd(group, event);
+
+       return metadata->fd;
+}
+
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+static struct fanotify_response_event *dequeue_re(struct fsnotify_group *group,
+                                                 __s32 fd)
+{
+       struct fanotify_response_event *re, *return_re = NULL;
+
+       mutex_lock(&group->fanotify_data.access_mutex);
+       list_for_each_entry(re, &group->fanotify_data.access_list, list) {
+               if (re->fd != fd)
+                       continue;
+
+               list_del_init(&re->list);
+               return_re = re;
+               break;
+       }
+       mutex_unlock(&group->fanotify_data.access_mutex);
+
+       pr_debug("%s: found return_re=%p\n", __func__, return_re);
+
+       return return_re;
+}
+
+static int process_access_response(struct fsnotify_group *group,
+                                  struct fanotify_response *response_struct)
+{
+       struct fanotify_response_event *re;
+       __s32 fd = response_struct->fd;
+       __u32 response = response_struct->response;
+
+       pr_debug("%s: group=%p fd=%d response=%d\n", __func__, group,
+                fd, response);
+       /*
+        * make sure the response is valid, if invalid we do nothing and either
+        * userspace can send a valid responce or we will clean it up after the
+        * timeout
+        */
+       switch (response) {
+       case FAN_ALLOW:
+       case FAN_DENY:
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       if (fd < 0)
+               return -EINVAL;
+
+       re = dequeue_re(group, fd);
+       if (!re)
+               return -ENOENT;
+
+       re->event->response = response;
+
+       wake_up(&group->fanotify_data.access_waitq);
+
+       kmem_cache_free(fanotify_response_event_cache, re);
+
+       return 0;
+}
+
+static int prepare_for_access_response(struct fsnotify_group *group,
+                                      struct fsnotify_event *event,
+                                      __s32 fd)
+{
+       struct fanotify_response_event *re;
+
+       if (!(event->mask & FAN_ALL_PERM_EVENTS))
+               return 0;
+
+       re = kmem_cache_alloc(fanotify_response_event_cache, GFP_KERNEL);
+       if (!re)
+               return -ENOMEM;
+
+       re->event = event;
+       re->fd = fd;
+
+       mutex_lock(&group->fanotify_data.access_mutex);
+       list_add_tail(&re->list, &group->fanotify_data.access_list);
+       mutex_unlock(&group->fanotify_data.access_mutex);
+
+       return 0;
+}
+
+static void remove_access_response(struct fsnotify_group *group,
+                                  struct fsnotify_event *event,
+                                  __s32 fd)
+{
+       struct fanotify_response_event *re;
+
+       if (!(event->mask & FAN_ALL_PERM_EVENTS))
+               return;
+
+       re = dequeue_re(group, fd);
+       if (!re)
+               return;
+
+       BUG_ON(re->event != event);
+
+       kmem_cache_free(fanotify_response_event_cache, re);
+
+       return;
+}
+#else
+static int prepare_for_access_response(struct fsnotify_group *group,
+                                      struct fsnotify_event *event,
+                                      __s32 fd)
+{
+       return 0;
+}
+
+static void remove_access_response(struct fsnotify_group *group,
+                                  struct fsnotify_event *event,
+                                  __s32 fd)
+{
+       return 0;
+}
+#endif
+
+static ssize_t copy_event_to_user(struct fsnotify_group *group,
+                                 struct fsnotify_event *event,
+                                 char __user *buf)
+{
+       struct fanotify_event_metadata fanotify_event_metadata;
+       int fd, ret;
+
+       pr_debug("%s: group=%p event=%p\n", __func__, group, event);
+
+       fd = fill_event_metadata(group, &fanotify_event_metadata, event);
+       if (fd < 0)
+               return fd;
+
+       ret = prepare_for_access_response(group, event, fd);
+       if (ret)
+               goto out_close_fd;
+
+       ret = -EFAULT;
+       if (copy_to_user(buf, &fanotify_event_metadata, FAN_EVENT_METADATA_LEN))
+               goto out_kill_access_response;
+
+       return FAN_EVENT_METADATA_LEN;
+
+out_kill_access_response:
+       remove_access_response(group, event, fd);
+out_close_fd:
+       sys_close(fd);
+       return ret;
+}
+
+/* intofiy userspace file descriptor functions */
+static unsigned int fanotify_poll(struct file *file, poll_table *wait)
+{
+       struct fsnotify_group *group = file->private_data;
+       int ret = 0;
+
+       poll_wait(file, &group->notification_waitq, wait);
+       mutex_lock(&group->notification_mutex);
+       if (!fsnotify_notify_queue_is_empty(group))
+               ret = POLLIN | POLLRDNORM;
+       mutex_unlock(&group->notification_mutex);
+
+       return ret;
+}
+
+static ssize_t fanotify_read(struct file *file, char __user *buf,
+                            size_t count, loff_t *pos)
+{
+       struct fsnotify_group *group;
+       struct fsnotify_event *kevent;
+       char __user *start;
+       int ret;
+       DEFINE_WAIT(wait);
+
+       start = buf;
+       group = file->private_data;
+
+       pr_debug("%s: group=%p\n", __func__, group);
+
+       while (1) {
+               prepare_to_wait(&group->notification_waitq, &wait, TASK_INTERRUPTIBLE);
+
+               mutex_lock(&group->notification_mutex);
+               kevent = get_one_event(group, count);
+               mutex_unlock(&group->notification_mutex);
+
+               if (kevent) {
+                       ret = PTR_ERR(kevent);
+                       if (IS_ERR(kevent))
+                               break;
+                       ret = copy_event_to_user(group, kevent, buf);
+                       fsnotify_put_event(kevent);
+                       if (ret < 0)
+                               break;
+                       buf += ret;
+                       count -= ret;
+                       continue;
+               }
+
+               ret = -EAGAIN;
+               if (file->f_flags & O_NONBLOCK)
+                       break;
+               ret = -EINTR;
+               if (signal_pending(current))
+                       break;
+
+               if (start != buf)
+                       break;
+
+               schedule();
+       }
+
+       finish_wait(&group->notification_waitq, &wait);
+       if (start != buf && ret != -EFAULT)
+               ret = buf - start;
+       return ret;
+}
+
+static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t count, loff_t *pos)
+{
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+       struct fanotify_response response = { .fd = -1, .response = -1 };
+       struct fsnotify_group *group;
+       int ret;
+
+       group = file->private_data;
+
+       if (count > sizeof(response))
+               count = sizeof(response);
+
+       pr_debug("%s: group=%p count=%zu\n", __func__, group, count);
+
+       if (copy_from_user(&response, buf, count))
+               return -EFAULT;
+
+       ret = process_access_response(group, &response);
+       if (ret < 0)
+               count = ret;
+
+       return count;
+#else
+       return -EINVAL;
+#endif
+}
 
 static int fanotify_release(struct inode *ignored, struct file *file)
 {
@@ -19,15 +372,249 @@ static int fanotify_release(struct inode *ignored, struct file *file)
        return 0;
 }
 
+static long fanotify_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+       struct fsnotify_group *group;
+       struct fsnotify_event_holder *holder;
+       void __user *p;
+       int ret = -ENOTTY;
+       size_t send_len = 0;
+
+       group = file->private_data;
+
+       p = (void __user *) arg;
+
+       switch (cmd) {
+       case FIONREAD:
+               mutex_lock(&group->notification_mutex);
+               list_for_each_entry(holder, &group->notification_list, event_list)
+                       send_len += FAN_EVENT_METADATA_LEN;
+               mutex_unlock(&group->notification_mutex);
+               ret = put_user(send_len, (int __user *) p);
+               break;
+       }
+
+       return ret;
+}
+
 static const struct file_operations fanotify_fops = {
-       .poll           = NULL,
-       .read           = NULL,
+       .poll           = fanotify_poll,
+       .read           = fanotify_read,
+       .write          = fanotify_write,
        .fasync         = NULL,
        .release        = fanotify_release,
-       .unlocked_ioctl = NULL,
-       .compat_ioctl   = NULL,
+       .unlocked_ioctl = fanotify_ioctl,
+       .compat_ioctl   = fanotify_ioctl,
 };
 
+static void fanotify_free_mark(struct fsnotify_mark *fsn_mark)
+{
+       kmem_cache_free(fanotify_mark_cache, fsn_mark);
+}
+
+static int fanotify_find_path(int dfd, const char __user *filename,
+                             struct path *path, unsigned int flags)
+{
+       int ret;
+
+       pr_debug("%s: dfd=%d filename=%p flags=%x\n", __func__,
+                dfd, filename, flags);
+
+       if (filename == NULL) {
+               struct file *file;
+               int fput_needed;
+
+               ret = -EBADF;
+               file = fget_light(dfd, &fput_needed);
+               if (!file)
+                       goto out;
+
+               ret = -ENOTDIR;
+               if ((flags & FAN_MARK_ONLYDIR) &&
+                   !(S_ISDIR(file->f_path.dentry->d_inode->i_mode))) {
+                       fput_light(file, fput_needed);
+                       goto out;
+               }
+
+               *path = file->f_path;
+               path_get(path);
+               fput_light(file, fput_needed);
+       } else {
+               unsigned int lookup_flags = 0;
+
+               if (!(flags & FAN_MARK_DONT_FOLLOW))
+                       lookup_flags |= LOOKUP_FOLLOW;
+               if (flags & FAN_MARK_ONLYDIR)
+                       lookup_flags |= LOOKUP_DIRECTORY;
+
+               ret = user_path_at(dfd, filename, lookup_flags, path);
+               if (ret)
+                       goto out;
+       }
+
+       /* you can only watch an inode if you have read permissions on it */
+       ret = inode_permission(path->dentry->d_inode, MAY_READ);
+       if (ret)
+               path_put(path);
+out:
+       return ret;
+}
+
+static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
+                                           __u32 mask,
+                                           unsigned int flags)
+{
+       __u32 oldmask;
+
+       spin_lock(&fsn_mark->lock);
+       if (!(flags & FAN_MARK_IGNORED_MASK)) {
+               oldmask = fsn_mark->mask;
+               fsnotify_set_mark_mask_locked(fsn_mark, (oldmask & ~mask));
+       } else {
+               oldmask = fsn_mark->ignored_mask;
+               fsnotify_set_mark_ignored_mask_locked(fsn_mark, (oldmask & ~mask));
+       }
+       spin_unlock(&fsn_mark->lock);
+
+       if (!(oldmask & ~mask))
+               fsnotify_destroy_mark(fsn_mark);
+
+       return mask & oldmask;
+}
+
+static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
+                                        struct vfsmount *mnt, __u32 mask,
+                                        unsigned int flags)
+{
+       struct fsnotify_mark *fsn_mark = NULL;
+       __u32 removed;
+
+       fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
+       if (!fsn_mark)
+               return -ENOENT;
+
+       removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
+       fsnotify_put_mark(fsn_mark);
+       if (removed & group->mask)
+               fsnotify_recalc_group_mask(group);
+       if (removed & mnt->mnt_fsnotify_mask)
+               fsnotify_recalc_vfsmount_mask(mnt);
+
+       return 0;
+}
+
+static int fanotify_remove_inode_mark(struct fsnotify_group *group,
+                                     struct inode *inode, __u32 mask,
+                                     unsigned int flags)
+{
+       struct fsnotify_mark *fsn_mark = NULL;
+       __u32 removed;
+
+       fsn_mark = fsnotify_find_inode_mark(group, inode);
+       if (!fsn_mark)
+               return -ENOENT;
+
+       removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
+       /* matches the fsnotify_find_inode_mark() */
+       fsnotify_put_mark(fsn_mark);
+
+       if (removed & group->mask)
+               fsnotify_recalc_group_mask(group);
+       if (removed & inode->i_fsnotify_mask)
+               fsnotify_recalc_inode_mask(inode);
+
+       return 0;
+}
+
+static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
+                                      __u32 mask,
+                                      unsigned int flags)
+{
+       __u32 oldmask;
+
+       spin_lock(&fsn_mark->lock);
+       if (!(flags & FAN_MARK_IGNORED_MASK)) {
+               oldmask = fsn_mark->mask;
+               fsnotify_set_mark_mask_locked(fsn_mark, (oldmask | mask));
+       } else {
+               oldmask = fsn_mark->ignored_mask;
+               fsnotify_set_mark_ignored_mask_locked(fsn_mark, (oldmask | mask));
+               if (flags & FAN_MARK_IGNORED_SURV_MODIFY)
+                       fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY;
+       }
+       spin_unlock(&fsn_mark->lock);
+
+       return mask & ~oldmask;
+}
+
+static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
+                                     struct vfsmount *mnt, __u32 mask,
+                                     unsigned int flags)
+{
+       struct fsnotify_mark *fsn_mark;
+       __u32 added;
+
+       fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
+       if (!fsn_mark) {
+               int ret;
+
+               fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
+               if (!fsn_mark)
+                       return -ENOMEM;
+
+               fsnotify_init_mark(fsn_mark, fanotify_free_mark);
+               ret = fsnotify_add_mark(fsn_mark, group, NULL, mnt, 0);
+               if (ret) {
+                       fanotify_free_mark(fsn_mark);
+                       return ret;
+               }
+       }
+       added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
+       fsnotify_put_mark(fsn_mark);
+       if (added) {
+               if (added & ~group->mask)
+                       fsnotify_recalc_group_mask(group);
+               if (added & ~mnt->mnt_fsnotify_mask)
+                       fsnotify_recalc_vfsmount_mask(mnt);
+       }
+       return 0;
+}
+
+static int fanotify_add_inode_mark(struct fsnotify_group *group,
+                                  struct inode *inode, __u32 mask,
+                                  unsigned int flags)
+{
+       struct fsnotify_mark *fsn_mark;
+       __u32 added;
+
+       pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
+
+       fsn_mark = fsnotify_find_inode_mark(group, inode);
+       if (!fsn_mark) {
+               int ret;
+
+               fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
+               if (!fsn_mark)
+                       return -ENOMEM;
+
+               fsnotify_init_mark(fsn_mark, fanotify_free_mark);
+               ret = fsnotify_add_mark(fsn_mark, group, inode, NULL, 0);
+               if (ret) {
+                       fanotify_free_mark(fsn_mark);
+                       return ret;
+               }
+       }
+       added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
+       fsnotify_put_mark(fsn_mark);
+       if (added) {
+               if (added & ~group->mask)
+                       fsnotify_recalc_group_mask(group);
+               if (added & ~inode->i_fsnotify_mask)
+                       fsnotify_recalc_inode_mask(inode);
+       }
+       return 0;
+}
+
 /* fanotify syscalls */
 SYSCALL_DEFINE3(fanotify_init, unsigned int, flags, unsigned int, event_f_flags,
                unsigned int, priority)
@@ -40,8 +627,6 @@ SYSCALL_DEFINE3(fanotify_init, unsigned int, flags, unsigned int, event_f_flags,
 
        if (event_f_flags)
                return -EINVAL;
-       if (priority)
-               return -EINVAL;
 
        if (!capable(CAP_SYS_ADMIN))
                return -EACCES;
@@ -49,7 +634,7 @@ SYSCALL_DEFINE3(fanotify_init, unsigned int, flags, unsigned int, event_f_flags,
        if (flags & ~FAN_ALL_INIT_FLAGS)
                return -EINVAL;
 
-       f_flags = (O_RDONLY | FMODE_NONOTIFY);
+       f_flags = O_RDWR | FMODE_NONOTIFY;
        if (flags & FAN_CLOEXEC)
                f_flags |= O_CLOEXEC;
        if (flags & FAN_NONBLOCK)
@@ -60,6 +645,13 @@ SYSCALL_DEFINE3(fanotify_init, unsigned int, flags, unsigned int, event_f_flags,
        if (IS_ERR(group))
                return PTR_ERR(group);
 
+       group->priority = priority;
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+       mutex_init(&group->fanotify_data.access_mutex);
+       init_waitqueue_head(&group->fanotify_data.access_waitq);
+       INIT_LIST_HEAD(&group->fanotify_data.access_list);
+#endif
+
        fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags);
        if (fd < 0)
                goto out_put_group;
@@ -70,3 +662,115 @@ out_put_group:
        fsnotify_put_group(group);
        return fd;
 }
+
+SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
+                             __u64 mask, int dfd,
+                             const char  __user * pathname)
+{
+       struct inode *inode = NULL;
+       struct vfsmount *mnt = NULL;
+       struct fsnotify_group *group;
+       struct file *filp;
+       struct path path;
+       int ret, fput_needed;
+
+       pr_debug("%s: fanotify_fd=%d flags=%x dfd=%d pathname=%p mask=%llx\n",
+                __func__, fanotify_fd, flags, dfd, pathname, mask);
+
+       /* we only use the lower 32 bits as of right now. */
+       if (mask & ((__u64)0xffffffff << 32))
+               return -EINVAL;
+
+       if (flags & ~FAN_ALL_MARK_FLAGS)
+               return -EINVAL;
+       switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
+       case FAN_MARK_ADD:
+       case FAN_MARK_REMOVE:
+       case FAN_MARK_FLUSH:
+               break;
+       default:
+               return -EINVAL;
+       }
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+       if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD))
+#else
+       if (mask & ~(FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD))
+#endif
+               return -EINVAL;
+
+       filp = fget_light(fanotify_fd, &fput_needed);
+       if (unlikely(!filp))
+               return -EBADF;
+
+       /* verify that this is indeed an fanotify instance */
+       ret = -EINVAL;
+       if (unlikely(filp->f_op != &fanotify_fops))
+               goto fput_and_out;
+
+       ret = fanotify_find_path(dfd, pathname, &path, flags);
+       if (ret)
+               goto fput_and_out;
+
+       /* inode held in place by reference to path; group by fget on fd */
+       if (!(flags & FAN_MARK_MOUNT))
+               inode = path.dentry->d_inode;
+       else
+               mnt = path.mnt;
+       group = filp->private_data;
+
+       /* create/update an inode mark */
+       switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
+       case FAN_MARK_ADD:
+               if (flags & FAN_MARK_MOUNT)
+                       ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags);
+               else
+                       ret = fanotify_add_inode_mark(group, inode, mask, flags);
+               break;
+       case FAN_MARK_REMOVE:
+               if (flags & FAN_MARK_MOUNT)
+                       ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags);
+               else
+                       ret = fanotify_remove_inode_mark(group, inode, mask, flags);
+               break;
+       case FAN_MARK_FLUSH:
+               if (flags & FAN_MARK_MOUNT)
+                       fsnotify_clear_vfsmount_marks_by_group(group);
+               else
+                       fsnotify_clear_inode_marks_by_group(group);
+               fsnotify_recalc_group_mask(group);
+               break;
+       default:
+               ret = -EINVAL;
+       }
+
+       path_put(&path);
+fput_and_out:
+       fput_light(filp, fput_needed);
+       return ret;
+}
+
+#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
+asmlinkage long SyS_fanotify_mark(long fanotify_fd, long flags, __u64 mask,
+                                 long dfd, long pathname)
+{
+       return SYSC_fanotify_mark((int) fanotify_fd, (unsigned int) flags,
+                                 mask, (int) dfd,
+                                 (const char  __user *) pathname);
+}
+SYSCALL_ALIAS(sys_fanotify_mark, SyS_fanotify_mark);
+#endif
+
+/*
+ * fanotify_user_setup - Our initialization function.  Note that we cannnot return
+ * error because we have compiled-in VFS hooks.  So an (unlikely) failure here
+ * must result in panic().
+ */
+static int __init fanotify_user_setup(void)
+{
+       fanotify_mark_cache = KMEM_CACHE(fsnotify_mark, SLAB_PANIC);
+       fanotify_response_event_cache = KMEM_CACHE(fanotify_response_event,
+                                                  SLAB_PANIC);
+
+       return 0;
+}
+device_initcall(fanotify_user_setup);