kern/136257: Able to set an invalid netmask

[Andrew]

>Number:         136257
>Category:       kern
>Synopsis:       Able to set an invalid netmask
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Jul 02 22:30:04 UTC 2009
>Closed-Date:
>Last-Modified:
>Originator:     Andrew
>Release:        7.2-RELEASE-p2
>Organization:
Falcon Tech Systems
>Environment:
>Description:
I'm able to set an invalid netmask:

ifconfig bridge0 inet 192.168.8.1 netmask 0xd0452484;

bridge0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        ether 6a:7d:09:1a:3e:34
        inet 192.168.8.1 netmask 0xd0452484 broadcast 192.168.8.255
        id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15
        maxage 20 holdcnt 6 proto rstp maxaddr 100 timeout 1200
        root id 00:00:00:00:00:00 priority 32768 ifcost 0 port 0
        member: em0 flags=143<LEARNING,DISCOVER,AUTOEDGE,AUTOPTP>
                ifmaxaddr 0 port 1 priority 128 path cost 20000

Netstat output is then confusing:
192.0.0.0&0xd0452484  link#5    UC    0    0 bridge

I've also tested this on a non-bridge interface, gif0, em0. As inet corresponds to an IPv4 address, this seems invalid.
>How-To-Repeat:

>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: