diff --git a/drivers/at86rf2xx/at86rf2xx_netdev.c b/drivers/at86rf2xx/at86rf2xx_netdev.c
index 885c32d018..ae5e32a989 100644
--- a/drivers/at86rf2xx/at86rf2xx_netdev.c
+++ b/drivers/at86rf2xx/at86rf2xx_netdev.c
@@ -461,9 +461,8 @@ static int _get(netdev_t *netdev, netopt_t opt, void *val, size_t max_len)
 #endif /* MODULE_NETDEV_IEEE802154_OQPSK */
 #if AT86RF2XX_RANDOM_NUMBER_GENERATOR
         case NETOPT_RANDOM:
-            assert(max_len >= sizeof(uint32_t));
-            at86rf2xx_get_random(dev, (uint8_t*)val, sizeof(val));
-            break;
+            at86rf2xx_get_random(dev, (uint8_t*)val, max_len);
+            return max_len;
 #endif
         default:
             res = -ENOTSUP;