fanotify: move unrelated handling from copy_event_to_user()

Move code moving event structure to access_list from copy_event_to_user()
to fanotify_read() where it is more logical (so that we can immediately
see in the main loop that we either move the event to a different list
or free it).  Also move special error handling for permission events
from copy_event_to_user() to the main loop to have it in one place with
error handling for normal events.  This makes copy_event_to_user()
really only copy the event to user without any side effects.

Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index f1097f5..4e565c8 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -199,7 +199,7 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
 
        ret = fill_event_metadata(group, &fanotify_event_metadata, event, &f);
        if (ret < 0)
-               goto out;
+               return ret;
 
        fd = fanotify_event_metadata.fd;
        ret = -EFAULT;
@@ -208,16 +208,8 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
                goto out_close_fd;
 
 #ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (event->mask & FAN_ALL_PERM_EVENTS) {
-               struct fanotify_perm_event_info *pevent;
-
-               pevent = FANOTIFY_PE(event);
-               pevent->fd = fd;
-               spin_lock(&group->fanotify_data.access_lock);
-               list_add_tail(&pevent->fae.fse.list,
-                             &group->fanotify_data.access_list);
-               spin_unlock(&group->fanotify_data.access_lock);
-       }
+       if (event->mask & FAN_ALL_PERM_EVENTS)
+               FANOTIFY_PE(event)->fd = fd;
 #endif
 
        if (fd != FAN_NOFD)
@@ -229,13 +221,6 @@ out_close_fd:
                put_unused_fd(fd);
                fput(f);
        }
-out:
-#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
-       if (event->mask & FAN_ALL_PERM_EVENTS) {
-               FANOTIFY_PE(event)->response = FAN_DENY;
-               wake_up(&group->fanotify_data.access_waitq);
-       }
-#endif
        return ret;
 }
 
@@ -300,10 +285,23 @@ static ssize_t fanotify_read(struct file *file, char __user *buf,
                 * Permission events get queued to wait for response.  Other
                 * events can be destroyed now.
                 */
-               if (!(kevent->mask & FAN_ALL_PERM_EVENTS))
+               if (!(kevent->mask & FAN_ALL_PERM_EVENTS)) {
                        fsnotify_destroy_event(group, kevent);
-               if (ret < 0)
-                       break;
+                       if (ret < 0)
+                               break;
+               } else {
+#ifdef CONFIG_FANOTIFY_ACCESS_PERMISSIONS
+                       if (ret < 0) {
+                               FANOTIFY_PE(kevent)->response = FAN_DENY;
+                               wake_up(&group->fanotify_data.access_waitq);
+                               break;
+                       }
+                       spin_lock(&group->fanotify_data.access_lock);
+                       list_add_tail(&kevent->list,
+                                     &group->fanotify_data.access_list);
+                       spin_unlock(&group->fanotify_data.access_lock);
+#endif
+               }
                buf += ret;
                count -= ret;
        }