Message-ID: <3ef18a75-8a1a-aa28-47e8-cba3f60475c7@linux.dev>
Date:   Wed, 15 Mar 2023 18:39:50 +0800
MIME-Version: 1.0
Subject: Re: [PATCH v2 5/5] md: protect md_thread with a new disk level spin
 lock
Content-Language: en-US
To:     Yu Kuai <yukuai1@huaweicloud.com>, agk@redhat.com,
        snitzer@kernel.org, song@kernel.org
Cc:     linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org,
        yi.zhang@huawei.com, yangerkun@huawei.com,
        "yukuai (C)" <yukuai3@huawei.com>
References: <20230315061810.653263-1-yukuai1@huaweicloud.com>
 <20230315061810.653263-6-yukuai1@huaweicloud.com>
 <16613534-5482-23c5-fa97-cfaedecab3d7@linux.dev>
 <7cc22b63-a2f7-67ed-1a50-9fb415fadb81@huaweicloud.com>
From:   Guoqing Jiang <guoqing.jiang@linux.dev>
In-Reply-To: <7cc22b63-a2f7-67ed-1a50-9fb415fadb81@huaweicloud.com>
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On 3/15/23 18:02, Yu Kuai wrote:
> Hi,
>
> 在 2023/03/15 17:39, Guoqing Jiang 写道:
>>
>>
>> On 3/15/23 14:18, Yu Kuai wrote:
>>> From: Yu Kuai <yukuai3@huawei.com>
>>>
>>> Our test reports a uaf for 'mddev->sync_thread':
>>>
>>> T1                      T2
>>> md_start_sync
>>>   md_register_thread
>>>             raid1d
>>>              md_check_recovery
>>>               md_reap_sync_thread
>>>                md_unregister_thread
>>>                 kfree
>>>
>>>   md_wakeup_thread
>>>    wake_up
>>>    ->sync_thread was freed
>>
>> Better to provide the relevant uaf (user after free perhaps you mean)
>> log from the test.
> Ok, I'll add uaf report(the report is from v5.10) in the next version.

Can you also try with latest mainline instead of just against 5.10 kernel?

Thanks,
Guoqing