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Subject: Re: [PATCH] block: fix syzbot report UAF in bdev_free_inode()
To:     Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
        Zqiang <qiang.zhang1211@gmail.com>
Cc:     linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        axboe@kernel.dk
References: <20211009065951.11567-1-qiang.zhang1211@gmail.com>
 <ad09fde9-9655-fc28-4298-4b43d57cd76c@i-love.sakura.ne.jp>
From:   zhangqiang <zhangqiang@qcraft.ai>
Message-ID: <d1cf5746-360a-9cb1-a69f-020480994352@qcraft.ai>
Date:   Sat, 9 Oct 2021 17:42:55 +0800
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On 2021/10/9 下午5:34, Tetsuo Handa wrote:
> On 2021/10/09 15:59, Zqiang wrote:
>> The xa_insert() may be return error in __alloc_disk_node(), and the disk
>> object will be release, however there are two operations that will release
>> it, kfree(disk) and iput(disk->part0->bd_inode), the iput operations
>> will call call_rcu(), because the rcu callback executed is an asynchronous
>> actionthe, so when free disk object in rcu callback, the disk object haven
>> been released. solve it through a unified release action.
>>
>> Reported-by: syzbot+8281086e8a6fbfbd952a@syzkaller.appspotmail.com
>> Signed-off-by: Zqiang <qiang.zhang1211@gmail.com>
> Thanks. But my patch is ready for 5.15.
>
> https://lore.kernel.org/all/e6dd13c5-8db0-4392-6e78-a42ee5d2a1c4@i-love.sakura.ne.jp/T/#u


Thanks, there is a problem with my patch, your path is more suitable