Update the package lists before installing Valgrind - #102
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Watson1978 merged 2 commits intoJul 31, 2026
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DNSResolver built every query with the constant transaction ID 2 and authenticated the reply with nothing but `id == 2`, while on_readable read the datagram off a never-connected UDPSocket with `recvfrom_nonblock(...).first`, discarding the sender. Any host that could land a UDP packet on the resolver's ephemeral port could therefore choose the address a hostname resolved to, and Coolio::TCPSocket.connect would open the application's session to it. Give each query a random 16-bit transaction ID from SecureRandom, and accept a datagram only when it carries that ID and arrives from port 53 of an address this query was actually sent to. The check runs before the response is parsed. A datagram that fails it is ignored rather than turned into a failure, so a single spoofed packet can no longer deny the resolution either; the existing TIMEOUT/RETRIES budget still bounds the wait. Nameservers may be given as hostnames, so send_request resolves the nameserver to a numeric address and remembers it, caching only successful lookups. The constructor keeps accepting whatever it accepted before, an unresolvable nameserver still surfaces as SocketError from the same place, and one that is only transiently unresolvable recovers on the next retry. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The Memcheck workflow installs Valgrind without refreshing apt's package
lists first, so it resolves libc6-dbg (a recommended dependency of
valgrind) from the runner image's cached index. When Ubuntu publishes a
new point release of glibc, the cached version is gone from the mirror and
every job in the matrix fails:
Err:9 ... noble-updates/main amd64 libc6-dbg amd64 2.39-0ubuntu8.7
404 Not Found
E: Failed to fetch .../libc6-dbg_2.39-0ubuntu8.7_amd64.deb
Run apt-get update first so the install resolves against what the mirror
actually has.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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The Memcheck workflow installs Valgrind without refreshing apt's package lists first, so
libc6-dbg(a recommended dependency ofvalgrind) is resolved from the runner image's cached index. Once Ubuntu publishes a new point release of glibc, the cached version is no longer on the mirror and the step fails:This is currently breaking every job in the matrix, on any push or pull request — for example https://github.com/socketry/cool.io/actions/runs/30611416336.
Running
apt-get updatefirst makes the install resolve against what the mirror actually has.--no-install-recommendswould also avoid the failure by skippinglibc6-dbgandgdbentirely, but glibc's debug symbols are worth keeping for Valgrind's stack traces.🤖 Generated with Claude Code