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Date:   Mon, 23 May 2022 10:15:48 -0400
From:   Josef Bacik <josef@toxicpanda.com>
To:     Yu Kuai <yukuai3@huawei.com>
Cc:     axboe@kernel.dk, ming.lei@redhat.com, linux-block@vger.kernel.org,
        nbd@other.debian.org, linux-kernel@vger.kernel.org,
        yi.zhang@huawei.com
Subject: Re: [PATCH -next v3 5/6] nbd: fix possible overflow on 'first_minor'
 in nbd_dev_add()
Message-ID: <YouXFG5+HEie9muN@localhost.localdomain>
References: <20220521073749.3146892-1-yukuai3@huawei.com>
 <20220521073749.3146892-6-yukuai3@huawei.com>
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On Sat, May 21, 2022 at 03:37:48PM +0800, Yu Kuai wrote:
> From: Zhang Wensheng <zhangwensheng5@huawei.com>
> 
> When 'index' is a big numbers, it may become negative which forced
> to 'int'. then 'index << part_shift' might overflow to a positive
> value that is not greater than '0xfffff', then sysfs might complains
> about duplicate creation. Because of this, move the 'index' judgment
> to the front will fix it and be better.
> 
> Fixes: b0d9111a2d53 ("nbd: use an idr to keep track of nbd devices")
> Fixes: 940c264984fd ("nbd: fix possible overflow for 'first_minor' in nbd_dev_add()")
> Signed-off-by: Zhang Wensheng <zhangwensheng5@huawei.com>
> Signed-off-by: Yu Kuai <yukuai3@huawei.com>

Reviewed-by: Josef Bacik <josef@toxicpanda.com>

Thanks,

Josef