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From: Alex Bligh <alex@alex.org.uk>
To: Pablo Neira Ayuso <pablo@netfilter.org>,
	Alexey Dobriyan <adobriyan@gmail.com>
Cc: kaber@trash.net, netfilter-devel@vger.kernel.org,
	Alex Bligh <alex@alex.org.uk>
Subject: Re: [PATCH] netfilter: fix ->nfnl NULL oops
Date: Wed, 09 Nov 2011 19:06:13 +0000	[thread overview]
Message-ID: <739793C1875DFFB8AD91547F@nimrod.local> (raw)
In-Reply-To: <20111109143423.GA24158@1984>



--On 9 November 2011 15:34:23 +0100 Pablo Neira Ayuso <pablo@netfilter.org> 
wrote:

>> I recall myself writing that net->nfnl NULL check is racy or
>> something like that (but I can't find this email in archives).
>>
>> I've read the code once again, and I'm quite sure,
>> NULL ->nfnl check is correct if RCU precautions are made.
>>
>> Regarding ->report check, I think it's bogus.
>>
>> If there are no listeners, there are NO listeners
>> and whether to report back to userspace doesn't matter.
>>
>> I'm sure I'm missing something obvious here.
>>
>> Please, review.
>
> Alexey. This is a workaround. We have to make ctnl_notifier
> container-aware which is the real problem.

It is indeed a workaround. However, until we have a real solution,
we need a workaround, or we can trivially generate fatal oopses.
I am all for fixing it properly, but please can we leave the workaround
in place until we have the proper answer, as without this we see
machines die frequently.

-- 
Alex Bligh

  reply	other threads:[~2011-11-09 19:06 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-11-08 22:16 [PATCH] netfilter: fix ->nfnl NULL oops Alexey Dobriyan
2011-11-08 22:50 ` Alex Bligh
2011-11-09 14:35   ` Pablo Neira Ayuso
2011-11-09 19:04     ` Alex Bligh
2011-11-09 14:34 ` Pablo Neira Ayuso
2011-11-09 19:06   ` Alex Bligh [this message]
2011-11-15  9:56   ` Pablo Neira Ayuso
2011-11-15 10:13     ` Alex Bligh
2011-11-15 14:09       ` Pablo Neira Ayuso
2011-11-21 23:39       ` Pablo Neira Ayuso
2011-11-21 23:42         ` Pablo Neira Ayuso
2011-11-21 23:50         ` Alex Bligh
2011-11-22 14:23           ` Pablo Neira Ayuso

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