return err;
}
+/*
+ * Copy event-type-independent attributes that may be modified.
+ */
+static void perf_event_modify_copy_attr(struct perf_event_attr *to,
+ const struct perf_event_attr *from)
+{
+ to->sig_data = from->sig_data;
+}
+
static int perf_event_modify_attr(struct perf_event *event,
struct perf_event_attr *attr)
{
WARN_ON_ONCE(event->ctx->parent_ctx);
mutex_lock(&event->child_mutex);
+ /*
+ * Event-type-independent attributes must be copied before event-type
+ * modification, which will validate that final attributes match the
+ * source attributes after all relevant attributes have been copied.
+ */
+ perf_event_modify_copy_attr(&event->attr, attr);
err = func(event, attr);
if (err)
goto out;
list_for_each_entry(child, &event->child_list, child_list) {
+ perf_event_modify_copy_attr(&child->attr, attr);
err = func(child, attr);
if (err)
goto out;