Hello, I just noticed that NuttX responds with an ICMP port unreachable on UDP broadcasts. AFAIK this shouldn't happen.
I followed the code, and I found that the broadcast reaches udp_input.c: line 256, where the ICMP response is generated. There is a note there that indeed the ICMP shouldn't be sent if this is a broadcast. As I see, the ICMP code is left to check this condition. Within icmp_reply.c: line 105 I see that there is a check about broadcasts. My understanding is that this check is wrong. It checks for pure equality, between the destination IP and INADDR_BROADCAST. In my (quite typical) network, the broadcast IP is 192.168.1.255. The check expects to see exactly 255.255.255.255, so it fails to realise that this is a broadcast and responds nevertheless. Shall this check be fixed somehow? Or have I misunderstood something?
