Move .LocalAddr() out of goroutine (#4281)

I don't have theory why this panics, but concurrency has something to do
with it, so get the address before we call the goroutine.

See #4271

Signed-off-by: Miek Gieben <miek@miek.nl>
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Miek Gieben 2020-12-11 17:49:47 +01:00 committed by GitHub
parent 9db3a2a72e
commit 108d26ebea
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@ -49,11 +49,12 @@ func (c *Cache) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg)
servedStale.WithLabelValues(server).Inc()
// Adjust the time to get a 0 TTL in the reply built from a stale item.
now = now.Add(time.Duration(ttl) * time.Second)
addr := w.LocalAddr() // See https://github.com/coredns/coredns/issues/4271, unclear how, but pull this out of the goroutine, and get the address here.
go func() {
if !do {
setDo(rc)
}
crr := &ResponseWriter{Cache: c, state: state, server: server, prefetch: true, remoteAddr: w.LocalAddr(), do: do}
crr := &ResponseWriter{Cache: c, state: state, server: server, prefetch: true, remoteAddr: addr, do: do}
plugin.NextOrFailure(c.Name(), c.Next, ctx, crr, rc)
}()
}