Henning

So far the error seems to be fixed. Thank you for your help!

That seems to be working. But we will do some further testing next week. We also had the exception at another point in the same function where cb->tcpcb_rcvchain = NULL , but couldn't reproduce it again. Maybe it was caused by the same line? I will post an update next week if the error still occurs. while(cb->tcpcb_rcvchain) { if(FNET_TCP_COMP_GE(seq, fnet_ntohl(FNET_TCP_SEQ(cb->tcpcb_rcvchain)))) { if(FNET_TCP_COMP_GE(fnet_ntohl(FNET_TCP_SEQ(cb->tcpcb_rcvchain)) + cb->tcpcb_rcvchain->total_length...

Hi, we are getting a null pointer exception in the _fnet_tcp_add_inpbuf function when receiving a lot of small tcp packets of around 100 Bytes. The exception occurs because cb->tcpcb_rcvchain is null, see attached picture. /* Delete the repeated segment.*/ buf = cb->tcpcb_rcvchain; cb->tcpcb_rcvchain = cb->tcpcb_rcvchain->next_chain; /* Set the new size of the temporary buffer.*/ /* Error cb->tcpcb_rcvchain = 0x0 */ cb->tcpcb_count -= cb->tcpcb_rcvchain->total_length; _fnet_netbuf_free_chain(buf);...