i386/167202: Sending multiple IGMP packets crashes kernel

[Andrew McConachie]

>Number:         167202
>Category:       i386
>Synopsis:       Sending multiple IGMP packets crashes kernel
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-i386
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Apr 22 13:30:13 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Andrew McConachie
>Release:        9.0-RELEASE
>Organization:
>Environment:
FreeBSD crunch 9.0-RELEASE FreeBSD 9.0-RELEASE #0: Tue Jan  3 07:15:25 UTC 2012     root at obrian.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

>Description:
I'm writing an IGMP test-tool in Scapy/Python and keep hitting this bug.

Whenever I send too many IGMPv2 joins out an interface the kernel crashes.  I can recreate this easily every time on FreeBSD.  I'm running FreeBSD in VirtualBox 4.1.12 r77245.  I am also running Debian in VirtualBox with essentially the same setup and it doesn't crash.

Script to recreate as well as kernel dumps at http://www.depht.com/temp/igmpCrash.tgz

>How-To-Repeat:
Install Python/Scapy and run the script igmpCrash.py.  You'll need igmp.py from the contrib section of Scapy.

I installed both Python and Scapy from ports.

smutt at crunch:/home/smutt$ python --version
Python 2.7.2
smutt at crunch:/home/smutt$ scapy 
INFO: Can't import python gnuplot wrapper . Won't be able to plot.
INFO: Can't import PyX. Won't be able to use psdump() or pdfdump().
INFO: Can't import python Crypto lib. Won't be able to decrypt WEP.
INFO: Can't import python Crypto lib. Disabled certificate manipulation tools
Welcome to Scapy (2.2.0)
>Fix:


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