diff --git a/src/include/netif/bridgeif_opts.h b/src/include/netif/bridgeif_opts.h
index 1ed62285..4ca08479 100644
--- a/src/include/netif/bridgeif_opts.h
+++ b/src/include/netif/bridgeif_opts.h
@@ -69,6 +69,8 @@
 /** BRIDGEIF_MAX_PORTS: this is used to create a typedef used for forwarding
  * bit-fields: the number of bits required is this + 1 (for the internal/cpu port)
  * (63 is the maximum, resulting in an u64_t for the bit mask)
+ * ATTENTION: this controls the maximum number of the implementation only!
+ * The max. number of ports per bridge must still be passed via netif_add parameter!
  */
 #ifndef BRIDGEIF_MAX_PORTS
 #define BRIDGEIF_MAX_PORTS                  7
diff --git a/src/netif/bridgeif.c b/src/netif/bridgeif.c
index 33b4eec1..c8b84f90 100644
--- a/src/netif/bridgeif.c
+++ b/src/netif/bridgeif.c
@@ -608,6 +608,8 @@ bridgeif_init(struct netif *netif)
 
   init_data = (bridgeif_initdata_t *)netif->state;
   LWIP_ASSERT("init_data != NULL", (init_data != NULL));
+  LWIP_ASSERT("init_data->max_ports <= BRIDGEIF_MAX_PORTS",
+    init_data->max_ports <= BRIDGEIF_MAX_PORTS);
 
   alloc_len = sizeof(bridgeif_private_t) + (init_data->max_ports*sizeof(bridgeif_port_t) + (init_data->max_fdb_static_entries*sizeof(bridgeif_fdb_static_entry_t)));
   LWIP_DEBUGF(BRIDGEIF_DEBUG, ("bridgeif_init: allocating %d bytes for private data\n", (int)alloc_len));