From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira <pablo@eurodev.net>
Subject: Re: nfnetlink/ctnetlink - OOPS&panic
Date: Tue, 19 Apr 2005 14:04:06 +0200
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To: Krzysztof Oledzki <olenf@ans.pl>
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Krzysztof Oledzki wrote:
> Hello,
> 
> I have just compiled 2.6.11.7 kernel with nfnetlink/ctnetlink support 
> (from pom-ng-20050418). Unfortunately, during system startup, kernel 
> panics:
> 
> Unable to handle kernel NULL pointer dereference at virtual address 
> 000000b3
>  printing eip:
> *pde = 00000000
> Oops: 0000 [#1]
> PREEMPT
> Modules linked in: bonding

You've catch a race condition.

Since you've compiled nfnetlink and ctnetlink in kernel, not as module, 
it seems that ctnetlink registers the subsystem via 
nfnetlink_subsys_register before nfnetlink has created the netlink 
socket. Then you've received an event that has been sent to a 
non-existing netlink socket. I can cook an oops with that.

I'll fix it as soon as I get some spare time.

--
Pablo