diff --git a/programs/fuzz/common.c b/programs/fuzz/common.c
index 465a76e..4d58402 100644
--- a/programs/fuzz/common.c
+++ b/programs/fuzz/common.c
@@ -64,6 +64,9 @@
     if( p_rng != NULL ) {
         //use mbedtls_ctr_drbg_random to find bugs in it
         ret = mbedtls_ctr_drbg_random(p_rng, output, output_len);
+    } else {
+        //fall through to pseudo-random
+        ret = 0;
     }
 #else
     (void) p_rng;