[Dnsmasq-discuss] [BUG] Logged IDs incorrect

[Dominik Derigs]

Hey Simon,

We received reports that the IDs of some log lines can be
incorrect ("log-queries=extra" is enabled).

I attach three representative log snippets that highlight the
issue (comments therein). Logs 1 and 2 seem to have the same
reason. I'd have provided a patch but I'm not sure about the
exact code path in this case: How is the query "forwarded ... to"
without a "query[A] ... from ..." line?

Be that as it may, even when I'm unable to reproduce this myself,
the source of the wrong IDs seems to be in forward_query():

>   /* If a query is retried, use the log_id for the retry when
> logging the answer. */
>   forward->frec_src.log_id = daemon->log_id;

The issue seems clear: When dnsmasq retries the queries itself
(i.e. without a corresponding "query[...]" line in the log),
daemon->log_id still points to the previous (entirely unrelated)
query. Setting the ID is incorrect at this point.

The third log is somewhat different, it may be a separate issue.
I cannot reproduce the issue in the first two logs but I can pass
on a patch.

Best,
Dominik
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