We got a similar (same?) report[1] against ubuntu, and while I was able to reproduce it, I have no idea what the cause is.
What's interesting is that we couldn't reproduce the bug with debian at the time... I posted my findings in the samba upstream mailing list[2], but understandably that didn't gain much interest. Re-exporting NFS with quota via cifs feels like something that could hit all sorts of corner cases. 1. https://bugs.launchpad.net/ubuntu/+source/samba/+bug/2077725 2. https://lists.samba.org/archive/samba/2025-May/251555.html
