bin/89808: malformed Framed-IPv6-Prefix crashes PPP

[Francis Dupont]

>Number:         89808
>Category:       bin
>Synopsis:       malformed Framed-IPv6-Prefix crashes PPP
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Thu Dec 01 17:10:02 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Francis Dupont
>Release:        FreeBSD 5.4
>Organization:
Point6 c/o GET/ENST Bretagne
>Environment:
FreeBSD orion.ipv6.rennes.enst-bretagne.fr 5.4-RELEASE FreeBSD 5.4-RELEASE #0: Thu Sep  1 16:00:11 CEST 2005     dupont at orion.ipv6.rennes.enst-bretagne.fr:/usr/src/kame/freebsd5/sys/i386/compile/ORION  i386              
>Description:
When PPP (/usr/sbin/ppp) receives a mal formed Framed-IPv6-Prefix in a RADIUS accept message
the rad_cvt_ipv6prefix() function returns a NULL which is not tested.              
>How-To-Repeat:
Configure a RADIUS server with a bogus Framed-IPv6-Prefix (BTW freeradius doesn't check this
so it can trigger the issue.              
>Fix:
In /usr/src/usr.sbin/ppp/radius.c please check the return value from rad_cvt_ipv6prefix()!              
>Release-Note:
>Audit-Trail:
>Unformatted: