fanotify: Add pids to events

Pass the process identifiers of the triggering processes to fanotify
listeners: this information is useful for event filtering and logging.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index cf9c300..66e38fc 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -103,6 +103,7 @@
 	metadata->event_len = FAN_EVENT_METADATA_LEN;
 	metadata->vers = FANOTIFY_METADATA_VERSION;
 	metadata->mask = fanotify_outgoing_mask(event->mask);
+	metadata->pid = pid_vnr(event->tgid);
 	metadata->fd = create_fd(group, event);
 
 	return metadata->fd;