Dnsmasq 2.83 causes log spam

[Hannu Nyman]

Looks like the new dnsmasq 2.83 (and the patched 2.80 in 19.07) cause massive 
log spam, in style of:


Fri Jan 22 06:30:09 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Network unreachable
Fri Jan 22 06:30:14 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Network unreachable
Fri Jan 22 06:30:23 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Network unreachable
Fri Jan 22 06:30:25 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Address family not supported by protocol
Fri Jan 22 06:30:25 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Address family not supported by protocol
Fri Jan 22 06:30:28 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Address family not supported by protocol
Fri Jan 22 06:30:28 2021 daemon.err dnsmasq[14996]: failed to send packet: 
Address family not supported by protocol


Based on forum discussion and my own experience, this is apparently mainly 
related to Windows PCs and Macs that have ipv6.


This is being extensively discussed in the forum, starting from:

https://forum.openwrt.org/t/security-advisory-2021-01-19-1-dnsmasq-multiple-vulnerabilities/85903/22