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To:     "Zhang, Qiang" <Qiang.Zhang@windriver.com>,
        Hillf Danton <hdanton@sina.com>,
        "axboe@kernel.dk" <axboe@kernel.dk>
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From:   Pavel Begunkov <asml.silence@gmail.com>
Message-ID: <900206b7-cf22-8248-1130-89c8f9d5539b@gmail.com>
Date:   Mon, 24 May 2021 11:18:54 +0100
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On 5/24/21 10:19 AM, Zhang, Qiang wrote:
> On Mon, 24 May 2021 15:18:44 +0800
>> From: Zqiang <qiang.zhang@windriver.com>
>>
>> The syzbot report a UAF when iou-wrk accessing wqe of the hash
>> waitqueue. in the case of sharing a hash waitqueue between two
>> io-wq, when one of the io-wq is destroyed, all iou-wrk in this
>> io-wq are awakened, all wqe belonging to this io-wq are removed
>> from hash waitqueue, after that, all iou-wrk belonging to this
>> io-wq begin running, suppose following scenarios, wqe[0] and wqe[1]
>> belong to this io-wq, and these work has same hash value.

Zhang, btw check your mail encoding, should some plain unicode


-- 
Pavel Begunkov