diff --git a/src/session.c b/src/session.c
index 4e84803..fbd5094 100644
--- a/src/session.c
+++ b/src/session.c
@@ -2908,7 +2908,7 @@
 	smp->flags = SMP_F_VOL_TEST;
 	smp->type = SMP_T_UINT;
 	smp->data.uint = 0;
-	if (stkctr_entry(stkctr) != NULL) {
+	if (stkctr && stkctr_entry(stkctr)) {
 		void *ptr;
 
 		/* First, update gpc0_rate if it's tracked. Second, update its