malloc crashes since OpenLDAP 2.6.15 (or 2.6.14)

Hi

Shortly after upgrading from OpenLDAP 2.6.13 to 2.6.15 (from Symas repo on RHEL 8), we are seeing malloc crashes:

Sep 16 12:08:24 slapd[2358763]: free(): invalid pointer Sep 16 13:40:52 slapd[2377743]: malloc(): unaligned tcache chunk detected Sep 16 13:50:51 slapd[2416163]: double free or corruption (out)

Sep 16 12:23:04 slapd[2379983]: malloc(): unaligned tcache chunk detected Sep 16 12:48:31 slapd[2401167]: malloc(): unaligned tcache chunk detected Sep 16 13:24:48 slapd[2400058]: malloc(): unaligned fastbin chunk detected

We rolled back for now, what can we provide to help debug this?

Geert