diff --git a/core/net/ip/uip-udp-packet.c b/core/net/ip/uip-udp-packet.c
index 923661709..b40d7cc9f 100644
--- a/core/net/ip/uip-udp-packet.c
+++ b/core/net/ip/uip-udp-packet.c
@@ -51,12 +51,10 @@ void
 uip_udp_packet_send(struct uip_udp_conn *c, const void *data, int len)
 {
 #if UIP_UDP
-  if(data != NULL) {
+  if(data != NULL && len <= (UIP_BUFSIZE - (UIP_LLH_LEN + UIP_IPUDPH_LEN))) {
     uip_udp_conn = c;
     uip_slen = len;
-    memmove(&uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN], data,
-            len > UIP_BUFSIZE - UIP_LLH_LEN - UIP_IPUDPH_LEN?
-            UIP_BUFSIZE - UIP_LLH_LEN - UIP_IPUDPH_LEN: len);
+    memmove(&uip_buf[UIP_LLH_LEN + UIP_IPUDPH_LEN], data, len);
     uip_process(UIP_UDP_SEND_CONN);
 
 #if UIP_CONF_IPV6_MULTICAST