1 files changed, 36 insertions, 4 deletions
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index e3f7d09e5512..969f48742d72 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -207,7 +207,7 @@ static int synth_field_string_size(char *type)
 	if (len == 0)
 		return 0; /* variable-length string */
 
-	strncpy(buf, start, len);
+	memcpy(buf, start, len);
 	buf[len] = '\0';
 
 	err = kstrtouint(buf, 0, &size);
@@ -305,7 +305,7 @@ static const char *synth_field_fmt(char *type)
 	else if (strcmp(type, "gfp_t") == 0)
 		fmt = "%x";
 	else if (synth_field_is_string(type))
-		fmt = "%.*s";
+		fmt = "%s";
 	else if (synth_field_is_stack(type))
 		fmt = "%s";
 
@@ -612,7 +612,7 @@ static int __set_synth_event_print_fmt(struct synth_event *event,
 		fmt = synth_field_fmt(event->fields[i]->type);
 		pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s",
 				event->fields[i]->name, fmt,
-				i == event->n_fields - 1 ? "" : ", ");
+				i == event->n_fields - 1 ? "" : " ");
 	}
 	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"");
 
@@ -852,6 +852,38 @@ static struct trace_event_fields synth_event_fields_array[] = {
 	{}
 };
 
+static int synth_event_reg(struct trace_event_call *call,
+		    enum trace_reg type, void *data)
+{
+	struct synth_event *event = container_of(call, struct synth_event, call);
+
+	switch (type) {
+#ifdef CONFIG_PERF_EVENTS
+	case TRACE_REG_PERF_REGISTER:
+#endif
+	case TRACE_REG_REGISTER:
+		if (!try_module_get(event->mod))
+			return -EBUSY;
+		break;
+	default:
+		break;
+	}
+
+	int ret = trace_event_reg(call, type, data);
+
+	switch (type) {
+#ifdef CONFIG_PERF_EVENTS
+	case TRACE_REG_PERF_UNREGISTER:
+#endif
+	case TRACE_REG_UNREGISTER:
+		module_put(event->mod);
+		break;
+	default:
+		break;
+	}
+	return ret;
+}
+
 static int register_synth_event(struct synth_event *event)
 {
 	struct trace_event_call *call = &event->call;
@@ -881,7 +913,7 @@ static int register_synth_event(struct synth_event *event)
 		goto out;
 	}
 	call->flags = TRACE_EVENT_FL_TRACEPOINT;
-	call->class->reg = trace_event_reg;
+	call->class->reg = synth_event_reg;
 	call->class->probe = trace_event_raw_event_synth;
 	call->data = event;
 	call->tp = event->tp;