ipfw: ipfw: Adding record failed: Inappropriate ioctl for device

Hello,

running a small home brewn firewall appliance  based upon FreeBSD 14-STABLE and IPFW, I
switched the base to 15-STABLE (FreeBSD 15.0-STABLE #5 n280665-6eb4708a84d7: Sat Oct 11
09:08:00 CEST 2025 amd64).

Now I face a serious issue with formerly flawless running skripts filling ipfw tables and the
readynes of the system after a reboot.

tables:
creating some named tables.
Having a list of IPv4 and IPv6 addresses that needed to be blocked, like VoIP Blacklist with
over 35k lines. Each line (IPv4) is 

X.X.X.X/CIDR

Shell is /bin/sh.

Reading the file and filling the table like shown below;
tbl_block=foo

#/usr/bin/env sh
ipfw table $tbl_block create type addr or-flush
while read -r line
do ipfw table $tbl_block atomic add $line
done  < /some/path/to/block_file.txt

The block_file.txt looks like

[...]
45.143.220.228/32
68.64.211.117/32
113.141.70.204/32
77.247.110.245/32
103.211.36.18/32
156.96.63.238/32
185.53.88.2/32
185.53.88.14/32
52.8.201.128/32
113.141.70.184/32
115.236.54.2/32
50.17.48.216/32
77.247.108.138/32
77.247.110.216/32
171.76.62.142/32
77.247.110.227/32
62.4.15.163/32
158.69.242.200/32
185.53.88.129/32
102.165.39.82/32
103.231.139.130/32
69.142.172.14/32
148.76.71.148/32
82.70.244.121/32
77.247.109.72/32
52.41.52.34/32
[...]

While running the skript, each time an address is picked up and inserted to the table, I see
this on the console:

[...]
added(reverted): 45.143.220.228/32 0
ipfw: Adding record failed: Inappropriate ioctl for device
added(reverted): 68.64.211.117/32 0
ipfw: Adding record failed: Inappropriate ioctl for device
added(reverted): 113.141.70.204/32 0
ipfw: Adding record failed: Inappropriate ioctl for device
added(reverted): 77.247.110.245/32 0
ipfw: Adding record failed: Inappropriate ioctl for device

I never saw this happen on 14-STABLE with the very same scripts. What is the cause of this
ioctl issue?

Thanks and kind regards,

Oliver






-- 

A FreeBSD user