/ pdns Public
dnsdist: Check the flags to detect collisions in the packet cache #6747
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In the unlikely but quite real event two queries with the same qname, qtype and qclass but different EDNS options or flags end up with the same hash, the packet cache would return a answer that might
not be suitable for the query. Reduce the odds by checking the flags present in the dns header in addition to the qname, qtype and qclass.
For the same reason we might need to consider storing the ECS subnet if any.