Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: general protection fault in tomoyo_socket_sendmsg_permission
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Hillf Danton <hdanton@sina.com>,
        syzbot <syzbot+95ce4b142579611ef0a9@syzkaller.appspotmail.com>
Cc:     linux-kernel@vger.kernel.org,
        Andrey Konovalov <andreyknvl@google.com>,
        Valentina Manea <valentina.manea.m@gmail.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        syzkaller-bugs@googlegroups.com,
        Shuah Khan <skhan@linuxfoundation.org>
References: <000000000000647eff05b3f7e0d4@google.com>
 <20201113120055.11748-1-hdanton@sina.com>
 <5f71e0c1-d387-6d72-d8e4-edb11cf57f72@linuxfoundation.org>
 <ea4028b7-53f2-aeaf-76e7-69874efcdec5@I-love.SAKURA.ne.jp>
 <2b70d360-a293-4acb-ea6c-2badda5e8b8b@linuxfoundation.org>
 <9bdd3f10-bddb-bd87-d7ad-b4b706477006@i-love.sakura.ne.jp>
 <6b8da36f-a994-7604-77f4-52e29434605f@linuxfoundation.org>
 <5f9ec159-77d8-ffba-21d1-2810e059f998@i-love.sakura.ne.jp>
 <a06093f1-22b3-7d72-bc6c-f99f4e0d0de9@linuxfoundation.org>
 <40617d66-1334-13a0-de9b-bd7cc1155ce5@i-love.sakura.ne.jp>
 <43d8d6bf-53f3-11e6-894d-c257f7f4bd07@linuxfoundation.org>
 <4368349b-fc0c-6da3-a502-2733f953d271@i-love.sakura.ne.jp>
 <92a4c6ae-172d-91cb-b89e-8eb857fdfb3a@linuxfoundation.org>
 <d177302a-3050-41db-cf44-6d614fd0c3a0@i-love.sakura.ne.jp>
From:   Shuah Khan <skhan@linuxfoundation.org>
Message-ID: <e5cb1f77-cd4b-9d74-4f28-d613d5478704@linuxfoundation.org>
Date:   Thu, 11 Feb 2021 18:34:14 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.6.1
MIME-Version: 1.0
In-Reply-To: <d177302a-3050-41db-cf44-6d614fd0c3a0@i-love.sakura.ne.jp>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 2/10/21 6:14 PM, Tetsuo Handa wrote:
> (Dropping LSM ML because this is not a TOMOYO's bug.)
> 
> On 2021/02/11 4:29, Shuah Khan wrote:
>> This is a good find. I already replied to the thread to send a complete
>> fix.
> 
> As I said at https://lkml.kernel.org/r/f8cae6b1-8f84-0e6a-7d9c-fc4aec68f07b@i-love.sakura.ne.jp ,
> the as-is patch is effectively a complete fix. And applying the as-is patch should help spending
> syzbot resources for reproducing "general protection fault in tomoyo_socket_sendmsg_permission"
> with debug printk() patch applied, which in turn will help you in
> 
>> Right. I would like to get a clear understanding of how this condition
>> is triggered. I am not saying this isn't a problem. Understanding how
>> it is triggered helps find the best fix.
> 
> part. Therefore, I strongly expect you to apply this version now.
> 

Is there a reproducer for this problem?

thanks,
-- Shuah