diff --git a/drivers/net/rckemac.c b/drivers/net/rckemac.c
index 8f22e0a5..e13ef5d1 100644
--- a/drivers/net/rckemac.c
+++ b/drivers/net/rckemac.c
@@ -350,11 +350,11 @@ static void rckemacif_input(struct netif* netif, struct pbuf* p)
 		/* full packet send to tcpip_thread to process */
 		if ((err = mynetif->input(p, mynetif)) != ERR_OK) {
 			LWIP_DEBUGF(NETIF_DEBUG, ("rckemacif_input: IP input error %d\n", (int32_t) err));
-			pbuf_free(p);
+			pbuf_free_callback(p);
 		}
 		break;
 	default:
-		pbuf_free(p);
+		pbuf_free_callback(p);
 		break;
 	}
 }
diff --git a/drivers/net/rtl8139.c b/drivers/net/rtl8139.c
index 469f332e..fb1127db 100644
--- a/drivers/net/rtl8139.c
+++ b/drivers/net/rtl8139.c
@@ -135,11 +135,11 @@ static void rtl8139if_input(struct netif* netif, struct pbuf* p)
 		err = mynetif->input(p, mynetif);
 		if (err != ERR_OK) {
 			LWIP_DEBUGF(NETIF_DEBUG, ("rtl8139if_input: IP input error %d\n", (int32_t) err));
-			pbuf_free(p);
+			pbuf_free_callback(p);
 		}
 		break;
 	default:
-		pbuf_free(p);
+		pbuf_free_callback(p);
 		break;
 	}
 }