krb5-18.2: MDB_BAD_RSLOT: Invalid reuse of reader locktable slot

[Greg Hudson]

On 6/18/20 4:53 AM, rachit chokshi wrote:
> *LMDB read failure (path: /var/kerberos/krb5kdc/principal.mdb):
> MDB_BAD_RSLOT: Invalid reuse of reader locktable slot*

After some off-list debugging, I determined that the LMDB reader table
entries for krb5kdc and kadmind appear as stale to other processes and
can be reclaimed, because both daemons open the DB before daemonizing.

I have filed a ticket and a pull request:

https://krbdev.mit.edu/rt/Ticket/Display.html?id=8918
https://github.com/krb5/krb5/pull/1088