fix: correctly handle dns messages in our dns implementation #8768
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frezbo
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I wonder if we can add some tests too |
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Tests are incoming. |
smira
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internal/app/machined/pkg/controllers/k8s/templates/core-dns-template.yaml
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- By default, github.com/miekg/dns uses `dns.MinMsgSize` for UDP messages, which is 512 bytes. This is too small for some DNS request/responses, and can cause truncation and errors. This change sets the buffer size to `dns.DefaultMsgSize` 4096 bytes, which is the maximum size of a dns packet payload per RFC 6891. - We also retry the request if the response is truncated or previous connection was closed. - And finally we properly handle the case where the response is larger than the client buffer size, and we return a truncated correct response. Closes siderolabs#8763 Signed-off-by: Dmitriy Matrenichev <[email protected]>
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dns.MinMsgSizefor UDP messages, which is 512 bytes. This is too small for some DNS request/responses, and can cause truncation and errors. This change sets the buffer size todns.DefaultMsgSize4096 bytes, which is the maximum size of a dns packet payload per RFC 6891.
and we return a truncated correct response.
Closes #8763