musl - getnameinfo waits timeout with no DNS configured

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Message-ID: <CAC5pKWDVRrp9+hwpZVVAaV7HB_H0uSaUESF6D6UxuvLAT9r7SQ@mail.gmail.com>
Date: Mon, 15 Sep 2025 16:44:50 +0200
From: Gal Luspam <galluspam@...il.com>
To: musl@...ts.openwall.com
Subject: getnameinfo waits timeout with no DNS configured

Hi,
I noticed that on a system without dns configuration, a call to
getnameinfo() will return only after timeout, even if dns queries sent
to 127.0.0.1:53 have a prompt "icmp port unreachable" reply.
This leads for example to the issue of slow output of some iptables
commands (see https://devnonsense.com/posts/slow-iptables-reverse-dns/
). This issue is not showing on systems with glibc.
Is this behaviour by design? Any hints?

Thank you
Paolo

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