mdb.c:3240: Assertion 'len >= 0 && id <= env->me_pglast' failed in mdb_freelist_save()

Howdy,

I hate using issues to report crashes, but as far as I can tell, I have a very unmodified build that started crashing when the VM was migrated between hosts. I then ran a yum update to see if it helped, but no dice. It explicitly lists the same line in mdb.c every time so I think that could be helpful.

Linux 3.10.0-1062.18.1.el7.x86_64 #1 (closed) SMP Tue Mar 17 23:49:17 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux CentOS Linux release 7.8.2003 (Core)

P.S. If I run kresd on the command line it does run, but gives a warning: [system] warning: hard limit for number of file-descriptors is only 4096 but recommended value is 524288

kres-cache-gc[21289]: Knot Resolver Cache Garbage Collector, version 5.1.3
kres-cache-gc[21289]: mdb.c:3240: Assertion 'len >= 0 && id <= env->me_pglast' failed in mdb_freelist_save()
systemd[1]: kres-cache-gc.service: main process exited, code=killed, status=6/ABRT
systemd[1]: Unit kres-cache-gc.service entered failed state.
systemd[1]: kres-cache-gc.service failed.
systemd[1]: kres-cache-gc.service holdoff time over, scheduling restart.
systemd[1]: Stopped Knot Resolver Garbage Collector daemon.

Process: 21287 ExecStart=/usr/sbin/kresd -c /usr/lib64/knot-resolver/distro-preconfig.lua -c /etc/knot-resolver/kresd.conf -n (code=killed, signal=ABRT)
 Main PID: 21287 (code=killed, signal=ABRT)

systemd[1]: Failed to start Knot Resolver daemon.
systemd[1]: Unit kresd@1.service entered failed state.
systemd[1]: kresd@1.service failed.
systemd[1]: kresd@1.service holdoff time over, scheduling restart.
systemd[1]: Stopped Knot Resolver daemon.
systemd[1]: start request repeated too quickly for kresd@1.service
systemd[1]: Failed to start Knot Resolver daemon.
systemd[1]: Unit kresd@1.service entered failed state.
systemd[1]: kresd@1.service failed.

If there's anything I can do to provide further info, let me know.