Cisco VPN client freezes computer when using wireless wlan0

[jordi]

Hi all,
I have openSuSE 10.3 with kernel 2.6.22.13-0.3-default 64-bit on a DELL D830 laptop and the "vpnclient-linux-x86_64-4.8.01.0640-k9.tar" with patch "cisco_skbuff_offset.patch" compiled perfectly.

However, the vpnclient seems to only work when I use ethernet (eth0) connection. When I use wireless (wlan0) connection, the whole system freezes after I have established the tunnel and I need to restart the laptop. I have tried connecting with 2 different PCF files to 2 different gateways (1 for work with "TunnelingMode=1" IPsec over TCP 10000, the other at a university with "TunnelingMode=0" IPsec over UDP) and they both freeze my computer while using wireless "wlan0". With "eth0", the same PCF files do not freeze my computer. I have never modified the PCF files, they were given to me like this by the system administrator.

I have installed some other versions of vpnclient and the computer always freezes as soon as I connect vpnclient using wlan0 (again, it works with eth0). I suspect the problem might come from using the "iwlwifi" linux driver for the Intel 4965 wireless card. I have another laptop with openSuSE 10.3 32-bit but with an Intel 2915 card (which uses the ipw2200 driver), and the Cisco VPN client works well with both "wlan0" and "eth0".

Does anybody else have this kind of problem? Does anybody know a workaround to this problem? Do you guys think it could be the iwlwifi driver?

Any kind of feedback would be very appreciated.

[tuxx-home.at]

I think it might be the combination of the cisco vpnclient and the iwlwifi driver. I never experienced problems with ipw2100, ipw2200 and ipw3945, but I never
tried iwlwifi by now so maybe it's the iwlwifi driver as you already figured out.

Have you tried contacting the iwlwifi mailing list on this issue?
Can you see what gets logged to your kernel logfile (usually /var/log/kern.log) when the freeze happens?

Usually, kernel faults get printed to the text console so you might want to switch to tty1 (CTRL-ALT-F1) before establishing the VPN connection to be able
to see the error messages printed.

[alesstimec]

Hello..

I am experiencing the same problem with Cisco VPN client (vpnclient-linux-x86_64-4.8.01.0640-k9) on Ubuntu 7.10 (kernel 2.6.22-14).. I am using Intel Core2Duo and wireless (iwl4965 module).

The client successfully establishes the connection through wlan0.. i can ssh to any of the machines, but when i try http access or VNC to one of the machines the whole system freezes and i am forced to reboot...

There were no problems compiling the vnc client, but this constant freezing is really a major problem.

[tuxx-home.at]

I am using Intel Core2Duo and wireless (iwl4965 module).

Maybe I'm able to track this one down because I have a laptop that meets the requirements for reproducing this, but this might take a while.

[alesstimec]

please see the CORRECTION bellow...

Hi...

I installed the 2.6.24 kernel on my Ubuntu 7.10, applied the patch to the VPN client, installed it and now it works.. So the problem is with the 2.6.22 kernel..

Cheers,
Ales

CORRECTION ::::::

My computer still freezes when i try to use scp or vnc.... so the 2.6.24 kernel is NOT the solution to our problem.. must be a problem with the iwl4965 module

[jordi]

Hi,
Now, I am using openSUSE 10.3 with kernel 2.6.22.16-0.1-default and the computer still freezes when using wlan0. Does anybody know a workaround to get VPN to work without having to upgrade to kernel 2.6.24? Maybe, there is a problem with the VPN patch for kernel 2.6.22, and not with the kernel itself.

Jordi

[tuxx-home.at]

Now, I am using openSUSE 10.3 with kernel 2.6.22.16-0.1-default and the computer still freezes when using wlan0.

What's your iwlwifi version? I'm sure the iwlwifi version used in conjunction with 2.6.24 is much newer than yours is, isn't it?
By now I didn't have time to test it, but maybe I'll have some time for this later this day. I need to compile a 2.6.22 and 2.6.24 kernel both with iwlwifi enabled on my notebook and try to establish a VPN connection to my company. I hope that I can reproduce this, but this might take a while as I'm currently not at home and usually time doesn't permit such experiments currently

I don't think that the problem is related to the VPN patch, though. I think the problem relies either in the kernel itself or in the iwlwifi code as using the ipw3945 driver or any other WLAN driver for the Intel Wifi chips doesn't produce such errors. Unfortunately, if you have a 4965 Wifi chip you have no choice but using the iwlwifi driver to make sure that it is the cause for your problem.

[jordi]

Hi,
I have opensuse 10.3 (kernel 2.6.22.16-0.1-default) with iwlwifi 1.2.23 in a Core Duo 2 64-bit with Intel 4965. I upgraded from iwlwifi 1.2.0 to 1.2.23 via the updates repository. However, I do not recall having installed any mac80211 subsystem because it needed recompilation. Do you think that could be the source of my problem?

I really appreciate all your help.
Jordi

[tuxx-home.at]

However, I do not recall having installed any mac80211 subsystem because it needed recompilation.

The mac80211 subsystem is part of the kernel since i-don't-know-the-version-exactly
Of course there were many updates to the mac80211 subsystem too since 2.6.22 and as iwlwifi makes heavy use of this subsystem it might also be the reason
for the problem you're experiencing.

However, you can download the latest iwlwifi and mac80211 versions from [http://www.intellinuxwireless.org/] and build iwlwifi against the updated
mac80211 stack by not using the kernel internal mac80211 sourcecode. Basically, this should work without recompiling your kernel you just need to make sure
that the kernel's own mac80211 modules don't get loaded at boot time.

[jordi]

Dear all,
I think I might have a new clue about why the cisco VPN client freezes the computer when using the iwlwifi driver. After applying your patch "cisco_skbuff_offset.patch" to the "vpnclient-linux-x86_64-4.8.01.0640-k9", my computer freezes as soon as the tunnel is established. However, I have edited the file "interceptor.c" and moved (cut & paste) the 2 functions below:

static int supported_device(struct net_device* dev)
static BINDING * getbindingbydev(struct net_device *dev)

right after the "static struct net_device_stats *interceptor_stats(struct net_device *dev)" function. Now, I can browse the internet for a while after establishing the tunnel, but eventually the computer freezes again after 2-3 min.

Unfortunately, I am not very familiar with the vpnclient source code, but I can see that by moving up these two functions inside the interceptor.c file has made some improvement, and now my computer takes a while to freeze. Maybe, some variables (such as "dev") are used before being completely defined or something like that, and perhaps that freezes the computer? Please let me know if that would make any sense...

BTW, before posting this, I have uninstalled the vpnclient and installed it again without moving the "supported_device" and "getbindingbydev" functions, and then, my computer freezes immediately after establishing the tunnel. If I move these functions in "interceptor.c" (as I described above) and install the vpnclient again, the computer takes a while longer to freeze.

Jordi

[mio]

FYI: My laptop (Dell 630, intel dual core, 3945 wireless) is also freezing at the first network activity after connecting via the cisco vpn client (version 8.01.0640, unpatched). I am using the ipw3945 module, though. Kernel 2.6.22-14, Ubuntu 7.10.

[tuxx-home.at]

Hmm... will have a look at your inputs tomorrow. On my notebook (IBM Thinkpad z61p), I'm currently running 2.6.24.2 and had ipw3945 installed the last few months with no freezes at all. Yesterday I installed iwl3945 (the one available with 2.6.24) and still wasn't able to reproduce this, but I'll dig deeper. Thanks for your feedback so far.

[jordi]

Hi again,
I just wanted to point out that everybody (at least in this post) that is experiencing this freezing problem has a 64-bit processor (Intel Core Duo 2). I do not know if that could be the reason, but it is a strange coincidence.

Jordi

[tuxx-home.at]

Intel Core2Duo doesn't necessarily mean that it is a 64bit processor. allestimec and mio need to follow up here and tell us if they've 64bit systems too.

[clark]

Hi there. I just thought I'd add to this thread, as I am experiencing very similar issues using the cisco vpn client with my wireless internet connection. In fact, I recently installed an configured vpnc, hoping that would solve the problem, but there is no difference. I can connect fine, but after some time (anywhere between 1-10 minutes) the computer freezes and requires a hard restart.

I'm running Ubuntu 6.06 on a Toshiba satellite 1110 laptop, with a D-link airplus (DWL-G650) PCMCIA wireless card. Any help would be greatly appreciated.

Clark