kern/170096: Dyanamically-attached network interface will crash with VIMAGE enabled kernel

[Takanori Watanabe]

>Number:         170096
>Category:       kern
>Synopsis:       Dyanamically-attached network interface will crash with VIMAGE enabled kernel
>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:   Mon Jul 23 21:40:09 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Takanori Watanabe
>Release:        FreeBSD 10.0-CURRENT
>Organization:
>Environment:
FreeBSD konata.init-main.com 10.0-CURRENT FreeBSD 10.0-CURRENT #7 r222214:238558M: Thu Jul 19 02:07:57 JST 2012     takawata at konata.init-main.com:/sys/i386/compile/LIEUTENANT  i386

>Description:
In VIMAGE network stack, curvnet macro is frequently referenced. It is actually reference td_vnet member in curthread structure. Usual user thread has valid pointer in td_vnet, but kernel thread, by which some dynamic interface attached, have initialized with NULL, so kernel will crash when curvnet is referenced.


>How-To-Repeat:
Plug dynamic network interface, like USB wlan, bluetooth or something, and kernel will crash where VNET() is refenced, like ng_make_node_common();
(I confirmed in USB only, but it may not limited in USB if my idea is correct.)
>Fix:
None yet.

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