kern/59681: npf: missing locking around inpcb_lookup in uid/gid checks

[campbell+netbsd%mumble.net@localhost]

>Number:         59681
>Category:       kern
>Synopsis:       npf: missing locking around inpcb_lookup in uid/gid checks
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Oct 01 11:00:00 +0000 2025
>Originator:     Taylor R Campbell
>Release:        current, 11
>Organization:
The NpfBSD User Group
>Environment:
>Description:

	The inpcb_lookup function is not currently MP-safe -- it
	requires softnet_lock.  However, the new npf uid/gid checks
	call it without first taking softnet_lock.


>How-To-Repeat:

	code inspection


>Fix:

	1. mutex_enter/exit(softnet_lock)
	2. sprinkle assertions