[Unbound-users] unbound: fatal error: services/outside_network.c:

[Leo Bush]

Dear all,

We use unbound since more than a year already with great satisfaction 
and no issue for resolving 4 Mbps DNS traffic in average with DNSSEC 
enabled.

We used to have unbound 1.4.14.
At the end of August suddenly unbound stopped to work. The process 
killed itself with the following message in the logs:

/var/log/messages:Aug 28 19:35:22 hostname unbound: [7896:1] fatal 
error: services/outside_network.c:1504: serviced_callbacks: pointer 
whitelist fptr_whitelist_serviced_query(p->cb) failed

The machine was under no unusual CPU/Memory/Network load.

We thought, bad luck, started the process and everything was fine for 
one week, when suddenly again the same thing. Fatal error.

/var/log/messages:Sep  6 14:20:20 hostname unbound: [1503:0] fatal 
error: services/outside_network.c:1504: serviced_callbacks: pointer 
whitelist fptr_whitelist_serviced_query(p->cb) failed

Then we thought about our version being too old and we upgraded to the 
latest release unbound 1.4.18.

Now we are running unbound 1.4.18 since two weeks and today again:

/var/log/messages:Sep 28 13:59:53 hostname unbound: [1591:1] fatal 
error: services/outside_network.c:1510: serviced_callbacks: pointer 
whitelist fptr_whitelist_serviced_query(p->cb) failed


Sounds like a software bug?

kind regards

Leo Bush


By the way, even if I do not think it is related to this case, I would 
like to report on the following behavior, that we note:
Several times a day we notice short peaks (<10 minutes) in outgoing 
traffic (times 7). Even if the traffic is so much higher, we do not 
notice a performance issue on the server. CPU and Ram are still fine. 
DNS response times are fine too. A traffic analysis suggested a DNS 
amplification attack where the question is for ANY isc.org. This attack 
never was happening when unbound crashed.