From mboxrd@z Thu Jan  1 00:00:00 1970
From: Baozeng Ding <sploving1@gmail.com>
Subject: Re: net/ipv6: potential deadlock in do_ipv6_setsockopt
Date: Mon, 17 Oct 2016 17:54:57 +0800
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 <CAM_iQpWKfkkYzF6yb9fGQsieGwok196kqGtRNVVS_ULxZghyew@mail.gmail.com>
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Cc: Linux Kernel Network Developers <netdev@vger.kernel.org>
To: Cong Wang <xiyou.wangcong@gmail.com>
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Applied the patch to my test tree. I will tell you the result a few days later. Thank you.

On 2016/10/17 2:50, Cong Wang wrote:
> On Sun, Oct 16, 2016 at 6:34 AM, Baozeng Ding <sploving1@gmail.com> wrote:
>>  Possible unsafe locking scenario:
>>
>>        CPU0                    CPU1
>>        ----                    ----
>>   lock([  165.136033] sk_lock-AF_INET6
>> );
>>                                lock([  165.136033] rtnl_mutex
>> );
>>                                lock([  165.136033] sk_lock-AF_INET6
>> );
>>   lock([  165.136033] rtnl_mutex
>> );
>>
>>  *** DEADLOCK ***
> 
> This is caused by the conditional rtnl locking in do_ipv6_setsockopt().
> It looks like we miss the case of IPV6_ADDRFORM.
> 
> Please try the attached patch.
>