[Dnsmasq-discuss] [Patch] Fix for use-after-free in lookup_domain

[Dmitry Valter]

Hi everyone!

I've been using dnsmasq 2.86 as a libvirt resolver on my laptop. 
Sometimes, likely when VM had sent a query during network reconnects, 
dnsmasq had crashed with SIGSEGV.
Rebuilding with ASAN and a few config changes helped me to identify 
likely cause in use-after-free. The full trace is attached in 
asan-trace.txt.

Since patching it I had no crashes (for a few months now). I believe, 
this bug still can be triggered in master branch, so you may find this 
patch useful.

Patch is created against v2.87test8-2-g8e59220

-- 
Best regards, Dmitry
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