[Pkg-dns-devel] Segfault in Knot 2.4.2 on Debian

[Libor Peltan]

Hello Danilo,

thanks much for your report.

This is indeed a bug, and since we fortunately reproduced it easily, we 
fixed it already.

We plan to release the fix with Knot 2.4.3 next week.

If you can, you may compile Knot from recent sources in our git 
repository and check the fix.

To temporarily get rid of the problem, you can try deleting the journal 
(note that all zones are in common journal) and avoiding the situation 
when zonefile SOA serial gets out of sync.

Thanks,

Libor


Dne 6.4.2017 v 00:49 Danilo napsal(a):
> Hello
>
> I'm using knot (2.4.2-1+0~20170323113312.21+jessie~1.gbp7bbc33) on
> Debian Jessie via the Repository https://deb.knot-dns.cz/knot/.
>
> Every time I get a dynamic zone update (adding a TXT record for Let's
> Encrypt verification), Knot segfaults reproducibely. This has not
> happened with an older version (not sure when the errors started
> appearing, but surely less than 3 months ago).
>
> Here's the log:
>
> Apr 06 00:39:47 sepp knotd[14195]: 2017-04-06T00:39:47 info:
> [schlagzeilengenerator.ch.] DDNS, processing 1 updates
> Apr 06 00:39:47 sepp knotd[14195]: 2017-04-06T00:39:47 warning:
> [schlagzeilengenerator.ch.] discontinuity in chages history (2017011211
> -> 2017011206), dropping older changesets
> Apr 06 00:39:47 sepp systemd[1]: knot.service: main process exited,
> code=killed, status=11/SEGV
> Apr 06 00:39:47 sepp systemd[1]: Unit knot.service entered failed state.
> Apr 06 00:39:47 sepp systemd[1]: knot.service holdoff time over,
> scheduling restart.
> Apr 06 00:39:47 sepp systemd[1]: Stopping Knot DNS server...
> Apr 06 00:39:47 sepp systemd[1]: Starting Knot DNS server...
> Apr 06 00:39:47 sepp systemd[1]: Started Knot DNS server.
>
> Unfortunately I was unable to create a core dump, I'm used to
> coredumpctl which is not available on Debian 8.
>
> Any help is appreciated, since my Let's Encrypt certs are expiring soon
> and I set them all up to renew automatically via Knot DNS challenge :)
>
> Best,
> Danilo