kern/54098: pf and npf interfere each others

[yamt9999%gmail.com@localhost]

>Number:         54098
>Category:       kern
>Synopsis:       pf and npf interfere each others
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 04 11:05:00 +0000 2019
>Originator:     YAMAMOTO Takashi
>Release:        netbsd 8.0/amd64
>Organization:
>Environment:
NetBSD ushi 8.0 NetBSD 8.0 (GENERIC) #0: Tue Jul 17 14:59:51 UTC 2018  mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64
>Description:
- pf and npf don't work simultaneously because they use the same field. (if_pf_kif)

- on the other hand, there seems to be no mechanism to prevent them from being enabled simultaneously.

- it can be even more dangerous with module autoloading.

>How-To-Repeat:
"npfctl show" on a box with pf configured.

>Fix:
stop using the same field, or make them mutually exclusive.