diff --git a/net/ip/contiki/ip/tcpip.c b/net/ip/contiki/ip/tcpip.c
index 305e2014224..7ae49bdf9d4 100644
--- a/net/ip/contiki/ip/tcpip.c
+++ b/net/ip/contiki/ip/tcpip.c
@@ -183,9 +183,10 @@ check_for_tcp_syn(struct net_buf *buf)
 #endif /* UIP_TCP || UIP_CONF_IP_FORWARD */
 }
 /*---------------------------------------------------------------------------*/
-static void
+static uint8_t
 packet_input(struct net_buf *buf)
 {
+  uint8_t ret = 0;
 #if UIP_CONF_IP_FORWARD
   if(uip_len > 0) {
     tcpip_is_forwarding = 1;
@@ -211,8 +212,8 @@ packet_input(struct net_buf *buf)
 #else /* UIP_CONF_IP_FORWARD */
   if(uip_len(buf) > 0) {
     check_for_tcp_syn(buf);
-    uip_input(buf);
-    if(uip_len(buf) > 0) {
+    ret = uip_input(buf);
+    if(ret && uip_len(buf) > 0) {
 #if UIP_CONF_TCP_SPLIT
       uip_split_output(buf);
 #else /* UIP_CONF_TCP_SPLIT */
@@ -227,6 +228,7 @@ packet_input(struct net_buf *buf)
     }
   }
 #endif /* UIP_CONF_IP_FORWARD */
+  return ret;
 }
 /*---------------------------------------------------------------------------*/
 #if UIP_TCP
@@ -533,7 +535,12 @@ eventhandler(process_event_t ev, process_data_t data, struct net_buf *buf)
 #endif /* UIP_UDP */
 
     case PACKET_INPUT:
-      packet_input(buf);
+      if (!packet_input(buf)) {
+         /* failure, discard the net_buf here because the
+          * return value cannot be passed to driver any longer
+          */
+         net_buf_put(buf);
+      }
       break;
   };
 }
@@ -692,6 +699,8 @@ tcpip_ipv6_output(struct net_buf *buf)
         stimer_set(&nbr->sendns, uip_ds6_if.retrans_timer / 1000);
         nbr->nscount = 1;
       }
+
+      return 1; /* packet was passed to network successfully */
 #endif /* UIP_ND6_SEND_NA */
     } else {
 #if UIP_ND6_SEND_NA
@@ -741,7 +750,7 @@ tcpip_ipv6_output(struct net_buf *buf)
 
       return ret;
     }
-    return;
+    return 0; /* discard packet */
   }
   /* Multicast IP destination address. */
   ret = tcpip_output(buf, NULL);
diff --git a/net/ip/contiki/ip/uip.h b/net/ip/contiki/ip/uip.h
index cb20100b3f1..11cf8422b48 100644
--- a/net/ip/contiki/ip/uip.h
+++ b/net/ip/contiki/ip/uip.h
@@ -1544,7 +1544,7 @@ uip_ext_hdr_options_process(); */
  *
  * The actual uIP function which does all the work.
  */
-void uip_process(struct net_buf *buf, uint8_t flag);
+uint8_t uip_process(struct net_buf *buf, uint8_t flag);
 
   /* The following flags are passed as an argument to the uip_process()
    function. They are used to distinguish between the two cases where
diff --git a/net/ip/contiki/ipv6/sicslowpan.c b/net/ip/contiki/ipv6/sicslowpan.c
index 70aecac034d..b4ff084ac24 100644
--- a/net/ip/contiki/ipv6/sicslowpan.c
+++ b/net/ip/contiki/ipv6/sicslowpan.c
@@ -1602,7 +1602,7 @@ output(struct net_buf *buf, const uip_lladdr_t *localdest)
  * \note We do not check for overlapping sicslowpan fragments
  * (it is a SHALL in the RFC 4944 and should never happen)
  */
-static void
+static uint8_t
 input(struct net_buf *buf)
 {
   /* size of the IP packet (read from fragment) */
@@ -1713,7 +1713,7 @@ input(struct net_buf *buf)
        * being reassembled or the packet is not a fragment.
        */
       PRINTFI("sicslowpan input: Dropping 6lowpan packet that is not a fragment of the packet currently being reassembled\n");
-      return;
+      return 0;
     }
   } else {
     /*
@@ -1724,7 +1724,7 @@ input(struct net_buf *buf)
       /* We are currently not reassembling a packet, but have received a packet fragment
        * that is not the first one. */
       if(is_fragment && !first_fragment) {
-        return;
+        return 0;
       }
 
       sicslowpan_len(buf) = frag_size;
@@ -1771,7 +1771,7 @@ input(struct net_buf *buf)
       /* unknown header */
       PRINTFI("sicslowpan input: unknown dispatch: %u\n",
              PACKETBUF_HC1_PTR(buf)[PACKETBUF_HC1_DISPATCH]);
-      return;
+      return 0;
   }
    
     
@@ -1787,7 +1787,7 @@ input(struct net_buf *buf)
    */
   if(packetbuf_datalen(buf) < uip_packetbuf_hdr_len(buf)) {
     PRINTF("SICSLOWPAN: packet dropped due to header > total packet\n");
-    return;
+    return 0;
   }
   uip_packetbuf_payload_len(buf) = packetbuf_datalen(buf) - uip_packetbuf_hdr_len(buf);
 
@@ -1800,7 +1800,7 @@ input(struct net_buf *buf)
           "SICSLOWPAN: packet dropped, minimum required SICSLOWPAN_IP_BUF size: %d+%d+%d+%d=%d (current size: %d)\n",
           UIP_LLH_LEN, uip_uncomp_hdr_len(buf), (uint16_t)(frag_offset << 3),
           uip_packetbuf_payload_len(buf), req_size, sizeof(sicslowpan_buf(buf)));
-      return;
+      return 0;
     }
   }
 
@@ -1865,9 +1865,11 @@ input(struct net_buf *buf)
 #endif
 
     tcpip_input(buf);
+    return 1;
 #if SICSLOWPAN_CONF_FRAG
   }
 #endif /* SICSLOWPAN_CONF_FRAG */
+  return 0;
 }
 /** @} */
 
diff --git a/net/ip/contiki/ipv6/uip6.c b/net/ip/contiki/ipv6/uip6.c
index 7adef4200f8..f3029a62ed2 100644
--- a/net/ip/contiki/ipv6/uip6.c
+++ b/net/ip/contiki/ipv6/uip6.c
@@ -949,7 +949,7 @@ ext_hdr_options_process(struct net_buf *buf)
 
 
 /*---------------------------------------------------------------------------*/
-void
+uint8_t
 uip_process(struct net_buf *buf, uint8_t flag)
 {
 #if UIP_TCP
@@ -2321,7 +2321,7 @@ uip_process(struct net_buf *buf, uint8_t flag)
   UIP_STAT(++uip_stat.ip.sent);
   /* Return and let the caller do the actual transmission. */
   uip_flags(buf) = 0;
-  return;
+  return 1;
 
  drop:
   /* If there is an error, then just return the buffer to pool */
@@ -2333,7 +2333,7 @@ uip_process(struct net_buf *buf, uint8_t flag)
   uip_ext_len(buf) = 0;
   uip_ext_bitmap(buf) = 0;
   uip_flags(buf) = 0;
-  return;
+  return 0;
 }
 /*---------------------------------------------------------------------------*/
 uint16_t
diff --git a/net/ip/contiki/llsec/llsec.h b/net/ip/contiki/llsec/llsec.h
index 01c948ca80c..6ae55b1616f 100644
--- a/net/ip/contiki/llsec/llsec.h
+++ b/net/ip/contiki/llsec/llsec.h
@@ -85,7 +85,7 @@ struct llsec_driver {
    * Decrypts incoming frames;
    * filters out injected or replayed frames.
    */
-  void (* input)(struct net_buf *buf);
+  uint8_t (* input)(struct net_buf *buf);
   
   /** Returns the security-related overhead per frame in bytes */
   uint8_t (* get_overhead)(void);
diff --git a/net/ip/contiki/llsec/nullsec.c b/net/ip/contiki/llsec/nullsec.c
index 62521781eca..7f72e029336 100644
--- a/net/ip/contiki/llsec/nullsec.c
+++ b/net/ip/contiki/llsec/nullsec.c
@@ -80,10 +80,10 @@ on_frame_created(void)
   return 1;
 }
 /*---------------------------------------------------------------------------*/
-static void
+static uint8_t
 input(struct net_buf *buf)
 {
-  NETSTACK_NETWORK.input(buf);
+  return NETSTACK_NETWORK.input(buf);
 }
 /*---------------------------------------------------------------------------*/
 static uint8_t
diff --git a/net/ip/contiki/mac/csma.c b/net/ip/contiki/mac/csma.c
index 91bb130d9e7..60a380e8e2c 100644
--- a/net/ip/contiki/mac/csma.c
+++ b/net/ip/contiki/mac/csma.c
@@ -428,12 +428,13 @@ send_packet(struct net_buf *buf, mac_callback_t sent, void *ptr)
     PRINTF("csma: could not allocate neighbor, dropping packet\n");
   }
   mac_call_sent_callback(buf, sent, ptr, MAC_TX_ERR, 1);
+  return 0;
 }
 /*---------------------------------------------------------------------------*/
-static void
+static uint8_t
 input_packet(struct net_buf *buf)
 {
-  NETSTACK_LLSEC.input(buf);
+  return NETSTACK_LLSEC.input(buf);
 }
 /*---------------------------------------------------------------------------*/
 static int
diff --git a/net/ip/contiki/mac/mac.h b/net/ip/contiki/mac/mac.h
index 6c81d8d2f0a..34ae7f3c5ac 100644
--- a/net/ip/contiki/mac/mac.h
+++ b/net/ip/contiki/mac/mac.h
@@ -63,7 +63,7 @@ struct mac_driver {
   uint8_t (* send)(struct net_buf *buf, mac_callback_t sent_callback, void *ptr);
 
   /** Callback for getting notified of incoming packet. */
-  void (* input)(struct net_buf *buf);
+  uint8_t (* input)(struct net_buf *buf);
   
   /** Turn the MAC layer on. */
   int (* on)(void);
diff --git a/net/ip/contiki/mac/rdc.h b/net/ip/contiki/mac/rdc.h
index a3400b69e4b..acf280e1368 100644
--- a/net/ip/contiki/mac/rdc.h
+++ b/net/ip/contiki/mac/rdc.h
@@ -79,7 +79,7 @@ struct rdc_driver {
   uint8_t (* send_list)(struct net_buf *buf, mac_callback_t sent_callback, void *ptr, struct rdc_buf_list *list);
 
   /** Callback for getting notified of incoming packet. */
-  void (* input)(struct net_buf *buf);
+  uint8_t (* input)(struct net_buf *buf);
 
   /** Turn the MAC layer on. */
   int (* on)(void);
diff --git a/net/ip/contiki/mac/sicslowmac/sicslowmac.c b/net/ip/contiki/mac/sicslowmac/sicslowmac.c
index db0e22494b7..01eb719c6b4 100644
--- a/net/ip/contiki/mac/sicslowmac/sicslowmac.c
+++ b/net/ip/contiki/mac/sicslowmac/sicslowmac.c
@@ -200,7 +200,7 @@ send_list(struct net_buf *buf, mac_callback_t sent, void *ptr, struct rdc_buf_li
   return 1;
 }
 /*---------------------------------------------------------------------------*/
-static void
+static uint8_t
 input_packet(struct net_buf *buf)
 {
   frame802154_t frame;
@@ -239,13 +239,12 @@ input_packet(struct net_buf *buf)
     PRINTF(" receiver ");
     PRINTLLADDR(packetbuf_addr(buf, PACKETBUF_ADDR_RECEIVER));
     PRINTF(" len %u\n", packetbuf_datalen(buf));
-    NETSTACK_MAC.input(buf);
-    return;
+    return NETSTACK_MAC.input(buf);
   } else {
     PRINTF("6MAC: failed to parse hdr\n");
   }
 error:
-  net_buf_put(buf);
+  return 0;
 }
 /*---------------------------------------------------------------------------*/
 static int
diff --git a/net/ip/contiki/netstack.h b/net/ip/contiki/netstack.h
index 648cbcbdbd5..ff81eec6b51 100644
--- a/net/ip/contiki/netstack.h
+++ b/net/ip/contiki/netstack.h
@@ -123,7 +123,7 @@ struct network_driver {
   void (* init)(void);
 
   /** Callback for getting notified of incoming packet. */
-  void (* input)(struct net_buf *buf);
+  uint8_t (* input)(struct net_buf *buf);
 };
 
 extern const struct network_driver NETSTACK_NETWORK;
diff --git a/net/ip/contiki/uip-driver.c b/net/ip/contiki/uip-driver.c
index 0434798d68b..81daea3a9fd 100644
--- a/net/ip/contiki/uip-driver.c
+++ b/net/ip/contiki/uip-driver.c
@@ -75,7 +75,7 @@ init(void)
   tcpip_set_outputfunc(uip_driver_send);
 }
 /*--------------------------------------------------------------------*/
-static void
+static uint8_t
 input(struct net_buf *buf)
 {
   PRINTF("uip-driver(%p): input %d bytes\n", buf, packetbuf_datalen(buf));
@@ -84,9 +84,11 @@ input(struct net_buf *buf)
     memcpy(&uip_buf(buf)[UIP_LLH_LEN], packetbuf_dataptr(buf), packetbuf_datalen(buf));
     uip_len(buf) = packetbuf_datalen(buf);
     tcpip_input(buf);
+    return 1;
   } else {
     PRINTF("datalen %d MAX %d\n", packetbuf_datalen(buf), UIP_BUFSIZE - UIP_LLH_LEN);
     UIP_LOG("uip-driver: too long packet discarded");
+    return 0;
   }
 }
 /*--------------------------------------------------------------------*/