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Subject: Re: [PATCH] block: fix syzbot report UAF in bdev_free_inode()
To:     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>
From:   Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Message-ID: <ad09fde9-9655-fc28-4298-4b43d57cd76c@i-love.sakura.ne.jp>
Date:   Sat, 9 Oct 2021 18:34:43 +0900
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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