Description of problem:
Unbound crashed while being used as local resolver.

Version-Release number of selected component (if applicable):
unbound-1.7.3-10.fc28.x86_64

How reproducible:
not sure. it happened after long time.

Steps to Reproduce:
1. ??

Actual results:
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] notice: sendto failed: Address family not supported by protocol
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] notice: remote address is unknown (inet_ntop error) port 42115 (len 28)
dec 12 10:20:29 thozza-work-pc systemd[1]: unbound.service: Main process exited, code=dumped, status=6/ABRT
dec 12 10:20:29 thozza-work-pc systemd[1]: unbound.service: Failed with result 'core-dump'.


Expected results:
service does not crash

Additional info:
I have a core dump, but ABRT claimed it to be unusable. I tried to inspect it with GDB, but there does not seem to be any useful information.

...
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug: forwarder, ignoring referral from auth zone
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug: attempt to get extra 3 targets
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug: servselect ip4 10.11.5.19 port 53 (len 16)
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug:    rtt=256
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug: servselect ip4 10.38.5.26 port 53 (len 16)
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug:    rtt=76
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] debug: selrtt 76
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: sending query: b.root-servers.net. AAAA IN
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: mesh_run: end 1 recursion states (1 with reply, 0 detached), 2 waiting replies, 836 recursion replies sent, 0 replies dropped, 0 states jostled out
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: average recursion processing time 0.459386 sec
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: histogram of recursion processing times
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: [25%]=0.0310924 median[50%]=0.098304 [75%]=0.240299
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: lower(secs) upper(secs) recursions
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.000000    0.000001 109
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.000512    0.001024 1
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.001024    0.002048 1
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.002048    0.004096 3
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.004096    0.008192 2
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.008192    0.016384 14
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.016384    0.032768 88
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.032768    0.065536 116
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.065536    0.131072 168
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.131072    0.262144 150
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.262144    0.524288 93
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    0.524288    1.000000 35
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    1.000000    2.000000 9
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    2.000000    4.000000 33
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    4.000000    8.000000 8
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:    8.000000   16.000000 2
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info:   16.000000   32.000000 4
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] info: 0RDd mod1 cb b.root-servers.net. AAAA IN
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] notice: sendto failed: Address family not supported by protocol
dec 12 10:20:29 thozza-work-pc unbound[3069]: [3069:0] notice: remote address is unknown (inet_ntop error) port 42115 (len 28)
dec 12 10:20:29 thozza-work-pc systemd[1]: unbound.service: Main process exited, code=dumped, status=6/ABRT
dec 12 10:20:29 thozza-work-pc systemd[1]: unbound.service: Failed with result 'core-dump'.