2009-12-18 10:24:29 +08:00
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#include <linux/fanotify.h>
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2009-12-18 10:24:25 +08:00
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#include <linux/fcntl.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/file.h>
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2009-12-18 10:24:25 +08:00
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#include <linux/fs.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/anon_inodes.h>
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2009-12-18 10:24:25 +08:00
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#include <linux/fsnotify_backend.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/init.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/mount.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/namei.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/poll.h>
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2009-12-18 10:24:25 +08:00
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#include <linux/security.h>
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#include <linux/syscalls.h>
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2010-05-19 23:36:28 +08:00
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#include <linux/slab.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/types.h>
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2009-12-18 10:24:26 +08:00
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#include <linux/uaccess.h>
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#include <asm/ioctls.h>
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2009-12-18 10:24:25 +08:00
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2010-10-29 05:21:57 +08:00
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#define FANOTIFY_DEFAULT_MAX_EVENTS 16384
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2010-10-29 05:21:57 +08:00
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#define FANOTIFY_DEFAULT_MAX_MARKS 8192
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2010-10-29 05:21:58 +08:00
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#define FANOTIFY_DEFAULT_MAX_LISTENERS 128
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2010-10-29 05:21:57 +08:00
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2009-12-18 10:24:29 +08:00
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extern const struct fsnotify_ops fanotify_fsnotify_ops;
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2009-12-18 10:24:25 +08:00
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2009-12-18 10:24:26 +08:00
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static struct kmem_cache *fanotify_mark_cache __read_mostly;
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2009-12-18 10:24:34 +08:00
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static struct kmem_cache *fanotify_response_event_cache __read_mostly;
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struct fanotify_response_event {
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struct list_head list;
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__s32 fd;
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struct fsnotify_event *event;
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};
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2009-12-18 10:24:26 +08:00
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2009-12-18 10:24:26 +08:00
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/*
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* Get an fsnotify notification event if one exists and is small
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* enough to fit in "count". Return an error pointer if the count
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* is not large enough.
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*
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* Called with the group->notification_mutex held.
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*/
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static struct fsnotify_event *get_one_event(struct fsnotify_group *group,
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size_t count)
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{
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BUG_ON(!mutex_is_locked(&group->notification_mutex));
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pr_debug("%s: group=%p count=%zd\n", __func__, group, count);
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if (fsnotify_notify_queue_is_empty(group))
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return NULL;
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if (FAN_EVENT_METADATA_LEN > count)
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return ERR_PTR(-EINVAL);
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/* held the notification_mutex the whole time, so this is the
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* same event we peeked above */
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return fsnotify_remove_notify_event(group);
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}
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2009-12-18 10:24:26 +08:00
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static int create_fd(struct fsnotify_group *group, struct fsnotify_event *event)
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2009-12-18 10:24:26 +08:00
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{
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int client_fd;
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struct dentry *dentry;
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struct vfsmount *mnt;
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struct file *new_file;
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2009-12-18 10:24:26 +08:00
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pr_debug("%s: group=%p event=%p\n", __func__, group, event);
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2009-12-18 10:24:26 +08:00
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client_fd = get_unused_fd();
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if (client_fd < 0)
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return client_fd;
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2010-08-13 05:23:04 +08:00
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if (event->data_type != FSNOTIFY_EVENT_PATH) {
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2009-12-18 10:24:26 +08:00
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WARN_ON(1);
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put_unused_fd(client_fd);
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return -EINVAL;
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}
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/*
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* we need a new file handle for the userspace program so it can read even if it was
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* originally opened O_WRONLY.
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*/
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2010-08-13 05:23:04 +08:00
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dentry = dget(event->path.dentry);
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mnt = mntget(event->path.mnt);
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2009-12-18 10:24:26 +08:00
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/* it's possible this event was an overflow event. in that case dentry and mnt
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* are NULL; That's fine, just don't call dentry open */
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if (dentry && mnt)
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new_file = dentry_open(dentry, mnt,
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2010-07-28 22:18:37 +08:00
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group->fanotify_data.f_flags | FMODE_NONOTIFY,
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2009-12-18 10:24:26 +08:00
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current_cred());
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else
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new_file = ERR_PTR(-EOVERFLOW);
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if (IS_ERR(new_file)) {
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/*
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* we still send an event even if we can't open the file. this
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* can happen when say tasks are gone and we try to open their
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* /proc files or we try to open a WRONLY file like in sysfs
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* we just send the errno to userspace since there isn't much
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* else we can do.
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*/
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put_unused_fd(client_fd);
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client_fd = PTR_ERR(new_file);
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} else {
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fd_install(client_fd, new_file);
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}
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2009-12-18 10:24:26 +08:00
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return client_fd;
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2009-12-18 10:24:26 +08:00
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}
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2010-11-09 07:08:14 +08:00
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static int fill_event_metadata(struct fsnotify_group *group,
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2009-12-18 10:24:26 +08:00
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struct fanotify_event_metadata *metadata,
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struct fsnotify_event *event)
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{
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pr_debug("%s: group=%p metadata=%p event=%p\n", __func__,
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group, metadata, event);
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metadata->event_len = FAN_EVENT_METADATA_LEN;
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metadata->vers = FANOTIFY_METADATA_VERSION;
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2009-12-18 10:24:29 +08:00
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metadata->mask = event->mask & FAN_ALL_OUTGOING_EVENTS;
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2009-12-18 10:24:27 +08:00
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metadata->pid = pid_vnr(event->tgid);
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2009-12-18 10:24:26 +08:00
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metadata->fd = create_fd(group, event);
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2009-12-18 10:24:26 +08:00
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2009-12-18 10:24:26 +08:00
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return metadata->fd;
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2009-12-18 10:24:26 +08:00
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}
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2009-12-18 10:24:34 +08:00
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#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
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static struct fanotify_response_event *dequeue_re(struct fsnotify_group *group,
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__s32 fd)
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{
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struct fanotify_response_event *re, *return_re = NULL;
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mutex_lock(&group->fanotify_data.access_mutex);
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list_for_each_entry(re, &group->fanotify_data.access_list, list) {
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if (re->fd != fd)
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continue;
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list_del_init(&re->list);
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return_re = re;
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break;
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}
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mutex_unlock(&group->fanotify_data.access_mutex);
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pr_debug("%s: found return_re=%p\n", __func__, return_re);
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return return_re;
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}
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static int process_access_response(struct fsnotify_group *group,
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struct fanotify_response *response_struct)
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{
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struct fanotify_response_event *re;
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__s32 fd = response_struct->fd;
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__u32 response = response_struct->response;
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pr_debug("%s: group=%p fd=%d response=%d\n", __func__, group,
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fd, response);
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/*
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* make sure the response is valid, if invalid we do nothing and either
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* userspace can send a valid responce or we will clean it up after the
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* timeout
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*/
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switch (response) {
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case FAN_ALLOW:
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case FAN_DENY:
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break;
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default:
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return -EINVAL;
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}
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if (fd < 0)
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return -EINVAL;
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re = dequeue_re(group, fd);
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if (!re)
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return -ENOENT;
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re->event->response = response;
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wake_up(&group->fanotify_data.access_waitq);
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kmem_cache_free(fanotify_response_event_cache, re);
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return 0;
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}
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static int prepare_for_access_response(struct fsnotify_group *group,
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struct fsnotify_event *event,
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__s32 fd)
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{
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struct fanotify_response_event *re;
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if (!(event->mask & FAN_ALL_PERM_EVENTS))
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return 0;
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re = kmem_cache_alloc(fanotify_response_event_cache, GFP_KERNEL);
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if (!re)
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return -ENOMEM;
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re->event = event;
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re->fd = fd;
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mutex_lock(&group->fanotify_data.access_mutex);
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2010-08-19 00:25:50 +08:00
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if (group->fanotify_data.bypass_perm) {
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mutex_unlock(&group->fanotify_data.access_mutex);
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kmem_cache_free(fanotify_response_event_cache, re);
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event->response = FAN_ALLOW;
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return 0;
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}
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2009-12-18 10:24:34 +08:00
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list_add_tail(&re->list, &group->fanotify_data.access_list);
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mutex_unlock(&group->fanotify_data.access_mutex);
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return 0;
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}
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static void remove_access_response(struct fsnotify_group *group,
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struct fsnotify_event *event,
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__s32 fd)
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{
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struct fanotify_response_event *re;
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if (!(event->mask & FAN_ALL_PERM_EVENTS))
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return;
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re = dequeue_re(group, fd);
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if (!re)
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return;
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BUG_ON(re->event != event);
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kmem_cache_free(fanotify_response_event_cache, re);
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return;
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}
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#else
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static int prepare_for_access_response(struct fsnotify_group *group,
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struct fsnotify_event *event,
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__s32 fd)
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{
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return 0;
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}
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static void remove_access_response(struct fsnotify_group *group,
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struct fsnotify_event *event,
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__s32 fd)
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{
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2009-12-23 13:10:25 +08:00
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return;
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2009-12-18 10:24:34 +08:00
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}
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#endif
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2009-12-18 10:24:26 +08:00
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static ssize_t copy_event_to_user(struct fsnotify_group *group,
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struct fsnotify_event *event,
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char __user *buf)
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{
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struct fanotify_event_metadata fanotify_event_metadata;
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2009-12-18 10:24:34 +08:00
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int fd, ret;
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2009-12-18 10:24:26 +08:00
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pr_debug("%s: group=%p event=%p\n", __func__, group, event);
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2010-11-09 07:08:14 +08:00
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ret = fill_event_metadata(group, &fanotify_event_metadata, event);
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if (ret < 0)
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goto out;
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2009-12-18 10:24:34 +08:00
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2010-11-09 07:08:14 +08:00
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fd = ret;
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2009-12-18 10:24:34 +08:00
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ret = prepare_for_access_response(group, event, fd);
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if (ret)
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goto out_close_fd;
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2009-12-18 10:24:26 +08:00
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2009-12-18 10:24:34 +08:00
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ret = -EFAULT;
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2009-12-18 10:24:26 +08:00
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if (copy_to_user(buf, &fanotify_event_metadata, FAN_EVENT_METADATA_LEN))
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2009-12-18 10:24:34 +08:00
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goto out_kill_access_response;
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2009-12-18 10:24:26 +08:00
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return FAN_EVENT_METADATA_LEN;
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2009-12-18 10:24:34 +08:00
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out_kill_access_response:
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remove_access_response(group, event, fd);
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out_close_fd:
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sys_close(fd);
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2010-11-09 07:08:14 +08:00
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out:
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#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
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if (event->mask & FAN_ALL_PERM_EVENTS) {
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event->response = FAN_DENY;
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wake_up(&group->fanotify_data.access_waitq);
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}
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#endif
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2009-12-18 10:24:34 +08:00
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return ret;
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2009-12-18 10:24:26 +08:00
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}
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/* intofiy userspace file descriptor functions */
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static unsigned int fanotify_poll(struct file *file, poll_table *wait)
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{
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struct fsnotify_group *group = file->private_data;
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int ret = 0;
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poll_wait(file, &group->notification_waitq, wait);
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mutex_lock(&group->notification_mutex);
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if (!fsnotify_notify_queue_is_empty(group))
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ret = POLLIN | POLLRDNORM;
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mutex_unlock(&group->notification_mutex);
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return ret;
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}
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static ssize_t fanotify_read(struct file *file, char __user *buf,
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size_t count, loff_t *pos)
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{
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struct fsnotify_group *group;
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struct fsnotify_event *kevent;
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char __user *start;
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int ret;
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DEFINE_WAIT(wait);
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start = buf;
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group = file->private_data;
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pr_debug("%s: group=%p\n", __func__, group);
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while (1) {
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prepare_to_wait(&group->notification_waitq, &wait, TASK_INTERRUPTIBLE);
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mutex_lock(&group->notification_mutex);
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kevent = get_one_event(group, count);
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mutex_unlock(&group->notification_mutex);
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if (kevent) {
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ret = PTR_ERR(kevent);
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if (IS_ERR(kevent))
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break;
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ret = copy_event_to_user(group, kevent, buf);
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fsnotify_put_event(kevent);
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if (ret < 0)
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break;
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buf += ret;
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count -= ret;
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continue;
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}
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ret = -EAGAIN;
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|
|
if (file->f_flags & O_NONBLOCK)
|
|
|
|
break;
|
2010-10-29 18:06:42 +08:00
|
|
|
ret = -ERESTARTSYS;
|
2009-12-18 10:24:26 +08:00
|
|
|
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;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:34 +08:00
|
|
|
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
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
static int fanotify_release(struct inode *ignored, struct file *file)
|
|
|
|
{
|
|
|
|
struct fsnotify_group *group = file->private_data;
|
|
|
|
|
2010-08-19 00:25:50 +08:00
|
|
|
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
|
2010-10-29 05:21:59 +08:00
|
|
|
struct fanotify_response_event *re, *lre;
|
|
|
|
|
2010-08-19 00:25:50 +08:00
|
|
|
mutex_lock(&group->fanotify_data.access_mutex);
|
|
|
|
|
|
|
|
group->fanotify_data.bypass_perm = true;
|
|
|
|
|
|
|
|
list_for_each_entry_safe(re, lre, &group->fanotify_data.access_list, list) {
|
|
|
|
pr_debug("%s: found group=%p re=%p event=%p\n", __func__, group,
|
|
|
|
re, re->event);
|
|
|
|
|
|
|
|
list_del_init(&re->list);
|
|
|
|
re->event->response = FAN_ALLOW;
|
|
|
|
|
|
|
|
kmem_cache_free(fanotify_response_event_cache, re);
|
|
|
|
}
|
|
|
|
mutex_unlock(&group->fanotify_data.access_mutex);
|
|
|
|
|
|
|
|
wake_up(&group->fanotify_data.access_waitq);
|
|
|
|
#endif
|
2009-12-18 10:24:26 +08:00
|
|
|
/* matches the fanotify_init->fsnotify_alloc_group */
|
|
|
|
fsnotify_put_group(group);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
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;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
static const struct file_operations fanotify_fops = {
|
2009-12-18 10:24:26 +08:00
|
|
|
.poll = fanotify_poll,
|
|
|
|
.read = fanotify_read,
|
2009-12-18 10:24:34 +08:00
|
|
|
.write = fanotify_write,
|
2009-12-18 10:24:26 +08:00
|
|
|
.fasync = NULL,
|
|
|
|
.release = fanotify_release,
|
2009-12-18 10:24:26 +08:00
|
|
|
.unlocked_ioctl = fanotify_ioctl,
|
|
|
|
.compat_ioctl = fanotify_ioctl,
|
llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-08-16 00:52:59 +08:00
|
|
|
.llseek = noop_llseek,
|
2009-12-18 10:24:26 +08:00
|
|
|
};
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
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;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:33 +08:00
|
|
|
static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
|
|
|
|
__u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:28 +08:00
|
|
|
{
|
|
|
|
__u32 oldmask;
|
|
|
|
|
|
|
|
spin_lock(&fsn_mark->lock);
|
2009-12-18 10:24:33 +08:00
|
|
|
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));
|
|
|
|
}
|
2009-12-18 10:24:28 +08:00
|
|
|
spin_unlock(&fsn_mark->lock);
|
|
|
|
|
|
|
|
if (!(oldmask & ~mask))
|
|
|
|
fsnotify_destroy_mark(fsn_mark);
|
|
|
|
|
|
|
|
return mask & oldmask;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:29 +08:00
|
|
|
static int fanotify_remove_vfsmount_mark(struct fsnotify_group *group,
|
2009-12-18 10:24:33 +08:00
|
|
|
struct vfsmount *mnt, __u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:28 +08:00
|
|
|
{
|
|
|
|
struct fsnotify_mark *fsn_mark = NULL;
|
2009-12-18 10:24:28 +08:00
|
|
|
__u32 removed;
|
2009-12-18 10:24:28 +08:00
|
|
|
|
2009-12-18 10:24:29 +08:00
|
|
|
fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
|
|
|
|
if (!fsn_mark)
|
|
|
|
return -ENOENT;
|
2009-12-18 10:24:28 +08:00
|
|
|
|
2009-12-18 10:24:33 +08:00
|
|
|
removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
|
2009-12-18 10:24:29 +08:00
|
|
|
fsnotify_put_mark(fsn_mark);
|
|
|
|
if (removed & mnt->mnt_fsnotify_mask)
|
|
|
|
fsnotify_recalc_vfsmount_mask(mnt);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2009-12-18 10:24:29 +08:00
|
|
|
static int fanotify_remove_inode_mark(struct fsnotify_group *group,
|
2009-12-18 10:24:33 +08:00
|
|
|
struct inode *inode, __u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:29 +08:00
|
|
|
{
|
|
|
|
struct fsnotify_mark *fsn_mark = NULL;
|
|
|
|
__u32 removed;
|
|
|
|
|
|
|
|
fsn_mark = fsnotify_find_inode_mark(group, inode);
|
2009-12-18 10:24:28 +08:00
|
|
|
if (!fsn_mark)
|
|
|
|
return -ENOENT;
|
|
|
|
|
2009-12-18 10:24:33 +08:00
|
|
|
removed = fanotify_mark_remove_from_mask(fsn_mark, mask, flags);
|
2009-12-18 10:24:27 +08:00
|
|
|
/* matches the fsnotify_find_inode_mark() */
|
2009-12-18 10:24:26 +08:00
|
|
|
fsnotify_put_mark(fsn_mark);
|
2009-12-18 10:24:29 +08:00
|
|
|
if (removed & inode->i_fsnotify_mask)
|
|
|
|
fsnotify_recalc_inode_mask(inode);
|
2009-12-18 10:24:28 +08:00
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:33 +08:00
|
|
|
static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
|
|
|
|
__u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:28 +08:00
|
|
|
{
|
2010-10-29 05:21:59 +08:00
|
|
|
__u32 oldmask = -1;
|
2009-12-18 10:24:28 +08:00
|
|
|
|
|
|
|
spin_lock(&fsn_mark->lock);
|
2009-12-18 10:24:33 +08:00
|
|
|
if (!(flags & FAN_MARK_IGNORED_MASK)) {
|
|
|
|
oldmask = fsn_mark->mask;
|
|
|
|
fsnotify_set_mark_mask_locked(fsn_mark, (oldmask | mask));
|
|
|
|
} else {
|
2010-10-29 05:21:59 +08:00
|
|
|
__u32 tmask = fsn_mark->ignored_mask | mask;
|
|
|
|
fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask);
|
2009-12-18 10:24:33 +08:00
|
|
|
if (flags & FAN_MARK_IGNORED_SURV_MODIFY)
|
|
|
|
fsn_mark->flags |= FSNOTIFY_MARK_FLAG_IGNORED_SURV_MODIFY;
|
2009-12-18 10:24:33 +08:00
|
|
|
}
|
2010-10-29 05:21:59 +08:00
|
|
|
|
|
|
|
if (!(flags & FAN_MARK_ONDIR)) {
|
|
|
|
__u32 tmask = fsn_mark->ignored_mask | FAN_ONDIR;
|
|
|
|
fsnotify_set_mark_ignored_mask_locked(fsn_mark, tmask);
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
spin_unlock(&fsn_mark->lock);
|
|
|
|
|
|
|
|
return mask & ~oldmask;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
|
2009-12-18 10:24:33 +08:00
|
|
|
struct vfsmount *mnt, __u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:26 +08:00
|
|
|
{
|
|
|
|
struct fsnotify_mark *fsn_mark;
|
2009-12-18 10:24:28 +08:00
|
|
|
__u32 added;
|
2010-11-10 01:18:16 +08:00
|
|
|
int ret = 0;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
|
|
|
|
if (!fsn_mark) {
|
2010-10-29 05:21:57 +08:00
|
|
|
if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks)
|
|
|
|
return -ENOSPC;
|
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
|
|
|
|
if (!fsn_mark)
|
2009-12-18 10:24:28 +08:00
|
|
|
return -ENOMEM;
|
2009-12-18 10:24:28 +08:00
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
fsnotify_init_mark(fsn_mark, fanotify_free_mark);
|
|
|
|
ret = fsnotify_add_mark(fsn_mark, group, NULL, mnt, 0);
|
2010-11-10 01:18:16 +08:00
|
|
|
if (ret)
|
|
|
|
goto err;
|
2009-12-18 10:24:28 +08:00
|
|
|
}
|
2009-12-18 10:24:33 +08:00
|
|
|
added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
|
2010-11-10 01:18:16 +08:00
|
|
|
|
2010-07-28 22:18:39 +08:00
|
|
|
if (added & ~mnt->mnt_fsnotify_mask)
|
|
|
|
fsnotify_recalc_vfsmount_mask(mnt);
|
2010-11-10 01:18:16 +08:00
|
|
|
err:
|
|
|
|
fsnotify_put_mark(fsn_mark);
|
|
|
|
return ret;
|
2009-12-18 10:24:28 +08:00
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
static int fanotify_add_inode_mark(struct fsnotify_group *group,
|
2009-12-18 10:24:33 +08:00
|
|
|
struct inode *inode, __u32 mask,
|
|
|
|
unsigned int flags)
|
2009-12-18 10:24:28 +08:00
|
|
|
{
|
|
|
|
struct fsnotify_mark *fsn_mark;
|
2009-12-18 10:24:28 +08:00
|
|
|
__u32 added;
|
2010-11-10 01:18:16 +08:00
|
|
|
int ret = 0;
|
2009-12-18 10:24:28 +08:00
|
|
|
|
|
|
|
pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2010-10-29 05:21:57 +08:00
|
|
|
/*
|
|
|
|
* If some other task has this inode open for write we should not add
|
|
|
|
* an ignored mark, unless that ignored mark is supposed to survive
|
|
|
|
* modification changes anyway.
|
|
|
|
*/
|
|
|
|
if ((flags & FAN_MARK_IGNORED_MASK) &&
|
|
|
|
!(flags & FAN_MARK_IGNORED_SURV_MODIFY) &&
|
|
|
|
(atomic_read(&inode->i_writecount) > 0))
|
|
|
|
return 0;
|
|
|
|
|
2009-12-18 10:24:27 +08:00
|
|
|
fsn_mark = fsnotify_find_inode_mark(group, inode);
|
2009-12-18 10:24:26 +08:00
|
|
|
if (!fsn_mark) {
|
2010-10-29 05:21:57 +08:00
|
|
|
if (atomic_read(&group->num_marks) > group->fanotify_data.max_marks)
|
|
|
|
return -ENOSPC;
|
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
fsn_mark = kmem_cache_alloc(fanotify_mark_cache, GFP_KERNEL);
|
|
|
|
if (!fsn_mark)
|
2009-12-18 10:24:28 +08:00
|
|
|
return -ENOMEM;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2009-12-18 10:24:28 +08:00
|
|
|
fsnotify_init_mark(fsn_mark, fanotify_free_mark);
|
|
|
|
ret = fsnotify_add_mark(fsn_mark, group, inode, NULL, 0);
|
2010-11-10 01:18:16 +08:00
|
|
|
if (ret)
|
|
|
|
goto err;
|
2009-12-18 10:24:26 +08:00
|
|
|
}
|
2009-12-18 10:24:33 +08:00
|
|
|
added = fanotify_mark_add_to_mask(fsn_mark, mask, flags);
|
2010-11-10 01:18:16 +08:00
|
|
|
|
2010-07-28 22:18:39 +08:00
|
|
|
if (added & ~inode->i_fsnotify_mask)
|
|
|
|
fsnotify_recalc_inode_mask(inode);
|
2010-11-10 01:18:16 +08:00
|
|
|
err:
|
|
|
|
fsnotify_put_mark(fsn_mark);
|
|
|
|
return ret;
|
2009-12-18 10:24:28 +08:00
|
|
|
}
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
/* fanotify syscalls */
|
2010-05-27 21:41:40 +08:00
|
|
|
SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
|
2009-12-18 10:24:25 +08:00
|
|
|
{
|
2009-12-18 10:24:26 +08:00
|
|
|
struct fsnotify_group *group;
|
|
|
|
int f_flags, fd;
|
2010-10-29 05:21:58 +08:00
|
|
|
struct user_struct *user;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2010-05-27 21:41:40 +08:00
|
|
|
pr_debug("%s: flags=%d event_f_flags=%d\n",
|
|
|
|
__func__, flags, event_f_flags);
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
2010-08-24 18:58:54 +08:00
|
|
|
return -EPERM;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
if (flags & ~FAN_ALL_INIT_FLAGS)
|
|
|
|
return -EINVAL;
|
|
|
|
|
2010-10-29 05:21:58 +08:00
|
|
|
user = get_current_user();
|
|
|
|
if (atomic_read(&user->fanotify_listeners) > FANOTIFY_DEFAULT_MAX_LISTENERS) {
|
|
|
|
free_uid(user);
|
|
|
|
return -EMFILE;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:34 +08:00
|
|
|
f_flags = O_RDWR | FMODE_NONOTIFY;
|
2009-12-18 10:24:26 +08:00
|
|
|
if (flags & FAN_CLOEXEC)
|
|
|
|
f_flags |= O_CLOEXEC;
|
|
|
|
if (flags & FAN_NONBLOCK)
|
|
|
|
f_flags |= O_NONBLOCK;
|
|
|
|
|
|
|
|
/* fsnotify_alloc_group takes a ref. Dropped in fanotify_release */
|
|
|
|
group = fsnotify_alloc_group(&fanotify_fsnotify_ops);
|
|
|
|
if (IS_ERR(group))
|
|
|
|
return PTR_ERR(group);
|
|
|
|
|
2010-10-29 05:21:58 +08:00
|
|
|
group->fanotify_data.user = user;
|
|
|
|
atomic_inc(&user->fanotify_listeners);
|
|
|
|
|
2010-07-28 22:18:37 +08:00
|
|
|
group->fanotify_data.f_flags = event_f_flags;
|
2009-12-18 10:24:34 +08:00
|
|
|
#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
|
2010-10-29 05:21:56 +08:00
|
|
|
switch (flags & FAN_ALL_CLASS_BITS) {
|
|
|
|
case FAN_CLASS_NOTIF:
|
|
|
|
group->priority = FS_PRIO_0;
|
|
|
|
break;
|
|
|
|
case FAN_CLASS_CONTENT:
|
|
|
|
group->priority = FS_PRIO_1;
|
|
|
|
break;
|
|
|
|
case FAN_CLASS_PRE_CONTENT:
|
|
|
|
group->priority = FS_PRIO_2;
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
fd = -EINVAL;
|
|
|
|
goto out_put_group;
|
|
|
|
}
|
2009-12-18 10:24:34 +08:00
|
|
|
|
2010-10-29 05:21:57 +08:00
|
|
|
if (flags & FAN_UNLIMITED_QUEUE) {
|
|
|
|
fd = -EPERM;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
goto out_put_group;
|
|
|
|
group->max_events = UINT_MAX;
|
|
|
|
} else {
|
|
|
|
group->max_events = FANOTIFY_DEFAULT_MAX_EVENTS;
|
|
|
|
}
|
2010-10-29 05:21:57 +08:00
|
|
|
|
2010-10-29 05:21:58 +08:00
|
|
|
if (flags & FAN_UNLIMITED_MARKS) {
|
|
|
|
fd = -EPERM;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
goto out_put_group;
|
|
|
|
group->fanotify_data.max_marks = UINT_MAX;
|
|
|
|
} else {
|
|
|
|
group->fanotify_data.max_marks = FANOTIFY_DEFAULT_MAX_MARKS;
|
|
|
|
}
|
2010-10-29 05:21:57 +08:00
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
fd = anon_inode_getfd("[fanotify]", &fanotify_fops, group, f_flags);
|
|
|
|
if (fd < 0)
|
|
|
|
goto out_put_group;
|
|
|
|
|
|
|
|
return fd;
|
|
|
|
|
|
|
|
out_put_group:
|
|
|
|
fsnotify_put_group(group);
|
|
|
|
return fd;
|
2009-12-18 10:24:25 +08:00
|
|
|
}
|
2009-12-18 10:24:26 +08:00
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
SYSCALL_DEFINE(fanotify_mark)(int fanotify_fd, unsigned int flags,
|
|
|
|
__u64 mask, int dfd,
|
|
|
|
const char __user * pathname)
|
2009-12-18 10:24:26 +08:00
|
|
|
{
|
2009-12-18 10:24:29 +08:00
|
|
|
struct inode *inode = NULL;
|
|
|
|
struct vfsmount *mnt = NULL;
|
2009-12-18 10:24:26 +08:00
|
|
|
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;
|
|
|
|
|
2009-12-18 10:24:29 +08:00
|
|
|
if (flags & ~FAN_ALL_MARK_FLAGS)
|
|
|
|
return -EINVAL;
|
2009-12-18 10:24:34 +08:00
|
|
|
switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
|
2009-12-18 10:24:29 +08:00
|
|
|
case FAN_MARK_ADD:
|
|
|
|
case FAN_MARK_REMOVE:
|
2009-12-18 10:24:34 +08:00
|
|
|
case FAN_MARK_FLUSH:
|
2009-12-18 10:24:29 +08:00
|
|
|
break;
|
|
|
|
default:
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
2010-10-29 05:21:59 +08:00
|
|
|
|
|
|
|
if (mask & FAN_ONDIR) {
|
|
|
|
flags |= FAN_MARK_ONDIR;
|
|
|
|
mask &= ~FAN_ONDIR;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:34 +08:00
|
|
|
#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
|
|
|
|
if (mask & ~(FAN_ALL_EVENTS | FAN_ALL_PERM_EVENTS | FAN_EVENT_ON_CHILD))
|
|
|
|
#else
|
2009-12-18 10:24:29 +08:00
|
|
|
if (mask & ~(FAN_ALL_EVENTS | FAN_EVENT_ON_CHILD))
|
2009-12-18 10:24:34 +08:00
|
|
|
#endif
|
2009-12-18 10:24:26 +08:00
|
|
|
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;
|
2010-10-29 05:21:56 +08:00
|
|
|
group = filp->private_data;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* group->priority == FS_PRIO_0 == FAN_CLASS_NOTIF. These are not
|
|
|
|
* allowed to set permissions events.
|
|
|
|
*/
|
|
|
|
ret = -EINVAL;
|
|
|
|
if (mask & FAN_ALL_PERM_EVENTS &&
|
|
|
|
group->priority == FS_PRIO_0)
|
|
|
|
goto fput_and_out;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
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 */
|
2009-12-18 10:24:29 +08:00
|
|
|
if (!(flags & FAN_MARK_MOUNT))
|
2009-12-18 10:24:29 +08:00
|
|
|
inode = path.dentry->d_inode;
|
|
|
|
else
|
|
|
|
mnt = path.mnt;
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
/* create/update an inode mark */
|
2009-12-18 10:24:34 +08:00
|
|
|
switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE | FAN_MARK_FLUSH)) {
|
2009-12-18 10:24:28 +08:00
|
|
|
case FAN_MARK_ADD:
|
2009-12-18 10:24:29 +08:00
|
|
|
if (flags & FAN_MARK_MOUNT)
|
2009-12-18 10:24:33 +08:00
|
|
|
ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags);
|
2009-12-18 10:24:29 +08:00
|
|
|
else
|
2009-12-18 10:24:33 +08:00
|
|
|
ret = fanotify_add_inode_mark(group, inode, mask, flags);
|
2009-12-18 10:24:28 +08:00
|
|
|
break;
|
|
|
|
case FAN_MARK_REMOVE:
|
2009-12-18 10:24:29 +08:00
|
|
|
if (flags & FAN_MARK_MOUNT)
|
2009-12-18 10:24:33 +08:00
|
|
|
ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags);
|
2009-12-18 10:24:29 +08:00
|
|
|
else
|
2009-12-18 10:24:33 +08:00
|
|
|
ret = fanotify_remove_inode_mark(group, inode, mask, flags);
|
2009-12-18 10:24:28 +08:00
|
|
|
break;
|
2009-12-18 10:24:34 +08:00
|
|
|
case FAN_MARK_FLUSH:
|
|
|
|
if (flags & FAN_MARK_MOUNT)
|
|
|
|
fsnotify_clear_vfsmount_marks_by_group(group);
|
|
|
|
else
|
|
|
|
fsnotify_clear_inode_marks_by_group(group);
|
|
|
|
break;
|
2009-12-18 10:24:28 +08:00
|
|
|
default:
|
|
|
|
ret = -EINVAL;
|
|
|
|
}
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
path_put(&path);
|
|
|
|
fput_and_out:
|
|
|
|
fput_light(filp, fput_needed);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
#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
|
|
|
|
|
2009-12-18 10:24:26 +08:00
|
|
|
/*
|
|
|
|
* 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);
|
2009-12-18 10:24:34 +08:00
|
|
|
fanotify_response_event_cache = KMEM_CACHE(fanotify_response_event,
|
|
|
|
SLAB_PANIC);
|
2009-12-18 10:24:26 +08:00
|
|
|
|
|
|
|
return 0;
|
2009-12-18 10:24:26 +08:00
|
|
|
}
|
2009-12-18 10:24:26 +08:00
|
|
|
device_initcall(fanotify_user_setup);
|