segfault in free_rdataset()
As reported in Support ticket #15331
> Program terminated with signal 11, Segmentation fault.
> #0 0x000000000052f983 in free_rdataset (rbtdb=0x7f8d15579b20, mctx=0x7f8d15541b10, rdataset=0x7f8d0a7efff8) at rbtdb.c:1903
> 1903 idx = rdataset->node->locknum;
>
> (gdb) bt
> #0 0x000000000052f983 in free_rdataset (rbtdb=0x7f8d15579b20, mctx=0x7f8d15541b10, rdataset=0x7f8d0a7efff8) at rbtdb.c:1903
> #1 0x00000000005301e9 in clean_stale_headers (rbtdb=0x7f8d15579b20, mctx=0x7f8d15541b10, top=0x7f8d0a816e30) at rbtdb.c:2200
> #2 0x0000000000530240 in clean_headerlist (header_head=0x7f8cfed71c60, rbtdb=0x7f8d15579b20) at rbtdb.c:2215
> #3 0x00000000005307d2 in clean_cache_node (rbtdb=0x7f8d15579b20, node=0x7f8cfed7db78, least_serial=0, nlock=<value optimized out>, tlock=57054,
> pruning=1048576) at rbtdb.c:2252
> #4 decrement_reference (rbtdb=0x7f8d15579b20, node=0x7f8cfed7db78, least_serial=0, nlock=<value optimized out>, tlock=57054, pruning=1048576) at rbtdb.c:2704
> #5 0x0000000000531122 in detachnode (db=<value optimized out>, targetp=0x7f8d1c1bffa8) at rbtdb.c:6278
> #6 0x00000000005312bf in rdataset_disassociate (rdataset=<value optimized out>) at rbtdb.c:10473
> #7 0x00000000005a2502 in dns_rdataset_disassociate (rdataset=0x7f8d132ac068) at rdataset.c:134
> #8 0x000000000050e7fe in msgresetnames (msg=0x7f8d1159c010, everything=<value optimized out>) at message.c:467
> #9 msgreset (msg=0x7f8d1159c010, everything=<value optimized out>) at message.c:551
> #10 0x000000000050f522 in dns_message_reset (msg=0x7f8d132ac068, intent=1) at message.c:818
> #11 0x0000000000421014 in ns_client_endrequest (client=0x7f8cfc0b7410) at client.c:1124
> #12 exit_check (client=0x7f8cfc0b7410) at client.c:650
> #13 0x0000000000422133 in ns_client_detach (clientp=<value optimized out>) at client.c:4929
> #14 0x000000000044fe89 in query_find (client=0x0, event=0x0, qtype=1) at query.c:13266
> #15 0x0000000000450d36 in query_resume (task=<value optimized out>, event=0x7f8d1627fd48) at query.c:5503
> #16 0x0000000000750003 in dispatch (uap=<value optimized out>) at task.c:1180
> #17 run (uap=<value optimized out>) at task.c:1352
> #18 0x00007f8dc3963fc9 in ?? ()
> #19 0x0000000000000000 in ?? ()
(Info requested by Evan - there's also a full backtrace attached to the Support ticket)