diff options
| -rw-r--r-- | fs/notify/fanotify/fanotify.c | 40 | ||||
| -rw-r--r-- | fs/notify/fanotify/fanotify.h | 7 | ||||
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 7 | ||||
| -rw-r--r-- | fs/notify/inotify/inotify_fsnotify.c | 19 | ||||
| -rw-r--r-- | fs/notify/notification.c | 24 | ||||
| -rw-r--r-- | include/linux/fsnotify_backend.h | 8 |
6 files changed, 56 insertions, 49 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 58772623f02a..0e792f5e3147 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -16,12 +16,6 @@ static bool should_merge(struct fsnotify_event *old_fsn, { struct fanotify_event_info *old, *new; -#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS - /* dont merge two permission events */ - if ((old_fsn->mask & FAN_ALL_PERM_EVENTS) && - (new_fsn->mask & FAN_ALL_PERM_EVENTS)) - return false; -#endif pr_debug("%s: old=%p new=%p\n", __func__, old_fsn, new_fsn); old = FANOTIFY_E(old_fsn); new = FANOTIFY_E(new_fsn); @@ -34,14 +28,23 @@ static bool should_merge(struct fsnotify_event *old_fsn, } /* and the list better be locked by something too! */ -static struct fsnotify_event *fanotify_merge(struct list_head *list, - struct fsnotify_event *event) +static int fanotify_merge(struct list_head *list, struct fsnotify_event *event) { struct fsnotify_event *test_event; bool do_merge = false; pr_debug("%s: list=%p event=%p\n", __func__, list, event); +#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS + /* + * Don't merge a permission event with any other event so that we know + * the event structure we have created in fanotify_handle_event() is the + * one we should check for permission response. + */ + if (event->mask & FAN_ALL_PERM_EVENTS) + return 0; +#endif + list_for_each_entry_reverse(test_event, list, list) { if (should_merge(test_event, event)) { do_merge = true; @@ -50,10 +53,10 @@ static struct fsnotify_event *fanotify_merge(struct list_head *list, } if (!do_merge) - return NULL; + return 0; test_event->mask |= event->mask; - return test_event; + return 1; } #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS @@ -149,7 +152,6 @@ static int fanotify_handle_event(struct fsnotify_group *group, int ret = 0; struct fanotify_event_info *event; struct fsnotify_event *fsn_event; - struct fsnotify_event *notify_fsn_event; BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS); BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY); @@ -188,21 +190,19 @@ static int fanotify_handle_event(struct fsnotify_group *group, event->response = 0; #endif - notify_fsn_event = fsnotify_add_notify_event(group, fsn_event, - fanotify_merge); - if (notify_fsn_event) { + ret = fsnotify_add_notify_event(group, fsn_event, fanotify_merge); + if (ret) { + BUG_ON(mask & FAN_ALL_PERM_EVENTS); /* Our event wasn't used in the end. Free it. */ fsnotify_destroy_event(group, fsn_event); - if (IS_ERR(notify_fsn_event)) - return PTR_ERR(notify_fsn_event); - /* We need to ask about a different events after a merge... */ - event = FANOTIFY_E(notify_fsn_event); - fsn_event = notify_fsn_event; + ret = 0; } #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS - if (fsn_event->mask & FAN_ALL_PERM_EVENTS) + if (mask & FAN_ALL_PERM_EVENTS) { ret = fanotify_get_response_from_access(group, event); + fsnotify_destroy_event(group, fsn_event); + } #endif return ret; } diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 0e90174a116a..32a2f034fb94 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -4,6 +4,13 @@ extern struct kmem_cache *fanotify_event_cachep; +/* + * Lifetime of the structure differs for normal and permission events. In both + * cases the structure is allocated in fanotify_handle_event(). For normal + * events the structure is freed immediately after reporting it to userspace. + * For permission events we free it only after we receive response from + * userspace. + */ struct fanotify_event_info { struct fsnotify_event fse; /* diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 1fd66abe5740..b6175fa11bf8 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -319,7 +319,12 @@ static ssize_t fanotify_read(struct file *file, char __user *buf, if (IS_ERR(kevent)) break; ret = copy_event_to_user(group, kevent, buf); - fsnotify_destroy_event(group, kevent); + /* + * Permission events get destroyed after we + * receive response + */ + if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) + fsnotify_destroy_event(group, kevent); if (ret < 0) break; buf += ret; diff --git a/fs/notify/inotify/inotify_fsnotify.c b/fs/notify/inotify/inotify_fsnotify.c index aad1a35e9af1..d5ee56348bb8 100644 --- a/fs/notify/inotify/inotify_fsnotify.c +++ b/fs/notify/inotify/inotify_fsnotify.c @@ -53,15 +53,13 @@ static bool event_compare(struct fsnotify_event *old_fsn, return false; } -static struct fsnotify_event *inotify_merge(struct list_head *list, - struct fsnotify_event *event) +static int inotify_merge(struct list_head *list, + struct fsnotify_event *event) { struct fsnotify_event *last_event; last_event = list_entry(list->prev, struct fsnotify_event, list); - if (!event_compare(last_event, event)) - return NULL; - return last_event; + return event_compare(last_event, event); } int inotify_handle_event(struct fsnotify_group *group, @@ -73,9 +71,8 @@ int inotify_handle_event(struct fsnotify_group *group, { struct inotify_inode_mark *i_mark; struct inotify_event_info *event; - struct fsnotify_event *added_event; struct fsnotify_event *fsn_event; - int ret = 0; + int ret; int len = 0; int alloc_len = sizeof(struct inotify_event_info); @@ -110,18 +107,16 @@ int inotify_handle_event(struct fsnotify_group *group, if (len) strcpy(event->name, file_name); - added_event = fsnotify_add_notify_event(group, fsn_event, inotify_merge); - if (added_event) { + ret = fsnotify_add_notify_event(group, fsn_event, inotify_merge); + if (ret) { /* Our event wasn't used in the end. Free it. */ fsnotify_destroy_event(group, fsn_event); - if (IS_ERR(added_event)) - ret = PTR_ERR(added_event); } if (inode_mark->mask & IN_ONESHOT) fsnotify_destroy_mark(inode_mark, group); - return ret; + return 0; } static void inotify_freeing_mark(struct fsnotify_mark *fsn_mark, struct fsnotify_group *group) diff --git a/fs/notify/notification.c b/fs/notify/notification.c index 952237b8e2d2..18b3c4427dca 100644 --- a/fs/notify/notification.c +++ b/fs/notify/notification.c @@ -79,15 +79,15 @@ void fsnotify_destroy_event(struct fsnotify_group *group, /* * Add an event to the group notification queue. The group can later pull this - * event off the queue to deal with. If the event is successfully added to the - * group's notification queue, a reference is taken on event. + * event off the queue to deal with. The function returns 0 if the event was + * added to the queue, 1 if the event was merged with some other queued event. */ -struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, - struct fsnotify_event *event, - struct fsnotify_event *(*merge)(struct list_head *, - struct fsnotify_event *)) +int fsnotify_add_notify_event(struct fsnotify_group *group, + struct fsnotify_event *event, + int (*merge)(struct list_head *, + struct fsnotify_event *)) { - struct fsnotify_event *return_event = NULL; + int ret = 0; struct list_head *list = &group->notification_list; pr_debug("%s: group=%p event=%p\n", __func__, group, event); @@ -98,14 +98,14 @@ struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, /* Queue overflow event only if it isn't already queued */ if (list_empty(&group->overflow_event.list)) event = &group->overflow_event; - return_event = event; + ret = 1; } if (!list_empty(list) && merge) { - return_event = merge(list, event); - if (return_event) { + ret = merge(list, event); + if (ret) { mutex_unlock(&group->notification_mutex); - return return_event; + return ret; } } @@ -115,7 +115,7 @@ struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, wake_up(&group->notification_waitq); kill_fasync(&group->fsn_fa, SIGIO, POLL_IN); - return return_event; + return ret; } /* diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h index 7d8d5e608594..3d286ff49ab0 100644 --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -322,10 +322,10 @@ extern int fsnotify_fasync(int fd, struct file *file, int on); extern void fsnotify_destroy_event(struct fsnotify_group *group, struct fsnotify_event *event); /* attach the event to the group notification queue */ -extern struct fsnotify_event *fsnotify_add_notify_event(struct fsnotify_group *group, - struct fsnotify_event *event, - struct fsnotify_event *(*merge)(struct list_head *, - struct fsnotify_event *)); +extern int fsnotify_add_notify_event(struct fsnotify_group *group, + struct fsnotify_event *event, + int (*merge)(struct list_head *, + struct fsnotify_event *)); /* true if the group notification queue is empty */ extern bool fsnotify_notify_queue_is_empty(struct fsnotify_group *group); /* return, but do not dequeue the first event on the notification queue */ |