VTun client segfault

[lc0277]

Binary package hint: vtun

I have a segfault with vtun client connecting to a remote host
"vtund[16758]: segfault at ffffffffaaac40c8 rip 00002aaaaace8872 rsp 00007ffffffbd480 error 6"

on client:

Aug 28 13:33:54 utica vtund[16758]: VTun client ver (Name,0) 11/01/2004 started
Aug 28 13:33:54 utica vtund[16758]: Connecting to malibu.tekila.org
Aug 28 13:33:54 utica vtund[16758]: Use SSL-aware challenge/response
Aug 28 13:33:54 utica vtund[16758]: Session lyon[malibu.hidden.org] opened
Aug 28 13:33:54 utica kernel: [12990.084642] tun: Universal TUN/TAP device driver, 1.6
Aug 28 13:33:54 utica kernel: [12990.084648] tun: (C) 1999-2004 Max Krasnyansky <email address hidden>
Aug 28 13:33:55 utica vtund[16758]: UDP connection initialized
Aug 28 13:33:55 utica vtund[16758]: LZO compression[level 9] initialized
Aug 28 13:33:55 utica vtund[16758]: BlowFish encryption initialized
Aug 28 13:34:07 utica kernel: [13002.359021] vtund[16758]: segfault at ffffffffaaac40c8 rip 00002aaaaace8872 rsp 00007ffffffbd480 error 6

client version:

Package: vtun
Architecture: amd64
Version: 2.6-4
Linux utica 2.6.15-26-amd64-generic #1 SMP PREEMPT Thu Aug 3 02:52:35 UTC 2006 x86_64 GNU/Linux

client conf:

lyon {
        passwd hidden
        type tun;
        up {
                ifconfig "%% 10.2.0.2 pointopoint 10.2.0.1";
                route "add -net 10.1.0.0 netmask 255.255.0.0 gw 10.2.0.1 metric 1";
        };
}

server: (not segfaulting and working OK)
Package: vtun
Maintainer: Morgon Kanter <email address hidden>
Architecture: i386
Version: 2.6-4

Linux malibu 2.6.12.2 #2 SMP Tue Jul 26 17:58:48 CEST 2005 i686 GNU/Linux
debian sid

server conf:

lyon {
        passwd hidden
        type tun;
        proto udp;
        compress lzo:9;
        encrypt yes;
        keepalive yes;
        up {
                ifconfig "%% 10.2.0.1 pointopoint 10.2.0.2";
                route "add -net 10.2.0.0 netmask 255.255.0.0 gw 10.2.0.2 metric
1";
        };
}

server log:
Aug 28 13:33:48 malibu vtund[19022]: Session lyon[134.XX.XX.XX:39221] opened
Aug 28 13:33:48 malibu kernel: tun: Universal TUN/TAP device driver, 1.6
Aug 28 13:33:48 malibu vtund[19022]: UDP connection initialized
Aug 28 13:33:48 malibu vtund[19022]: LZO compression[level 9] initialized
Aug 28 13:33:48 malibu vtund[19022]: BlowFish encryption initialized
Aug 28 13:33:48 malibu kernel: tun: (C) 1999-2004 Max Krasnyansky <email address hidden>
Aug 28 13:34:02 malibu vtund[19022]: Connection refused (111)
Aug 28 13:34:02 malibu vtund[19022]: Session lyon closed

[Gilles Pietri (gilou)]

Confirmed here, on AMD 64 architecture :
Sep 19 14:20:12 cameleon kernel: [33076.019565] vtund[2020]: segfault at ffffffffaaac40c8 rip 00002aaaaace8872 rsp 00007fffffc1dd10 error 6

I've got a similar config, and I can set the tunnel up, but whenever I try to use it (let's say trying to ping the other side) it crashes.

My kernel is 2.6.15-27-amd64-generic though, but I guess this won't change a lot.

I'm trying to compile it from the sources to see if I can make it work...

[Gilles Pietri (gilou)]

Having the same behaviour on amd-64 using dapper, and an up to date kernel

[Gilles Pietri (gilou)]

When I compiled it directly from the sources I have the same behaviour, so this has to be a vtund bug.
Looking in the devel ML of vtun, I found this :
http://sourceforge.net/mailarchive/forum.php?thread_id=8205403&forum_id=1827

Disabling compression worked for me ...

[frenet (renet-f)]

Using vtun 3.0.2-2ubuntu2 on x86_64 this bug is still showing when LZO compression is turned on, at least in client mode.
Same as on debian :
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=477707

Patch is available :
http://sourceforge.net/mailarchive/forum.php?thread_name=20081220215633.110005bc%40sics.se&forum_name=vtun-devel

And is reported to work

[Chuck Short (zulcss)]

Thanks

[Stefano Rivera (stefanor)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. However, I am closing it because the bug has been fixed in the latest development version of Ubuntu - Maverick Meerkat.

This is a significant bug in Ubuntu. If you need a fix for the bug in previous versions of Ubuntu, please do steps 1 and 2 of the SRU Procedure [1] to bring the need to a developer's attention.

[1]: https://wiki.ubuntu.com/StableReleaseUpdates#Procedure