Please, make sure your Linux kernel version is >= 5.6.7 or manually
cherry-pick this fix which was included starting that version.
Versions from 5.6.0 to 5.6.6 include this problem you describe.
See https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.6.7
Author: Stefano Brivio <sbrivio@xxxxxxxxxx>
Date: Wed Apr 1 17:14:38 2020 +0200
netfilter: nft_set_rbtree: Drop spurious condition for overlap detection on insertion
commit 72239f2795fab9a58633bd0399698ff7581534a3 upstream.
Thank you very much!
-MikeD
