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Message-ID: <9e3302ac-7e1e-0925-3da1-7c9070c51a3c@huawei.com>
Date:   Thu, 25 May 2023 21:20:07 +0800
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Subject: Re: [PATCH -next] block: Fix the partition start may overflow in
 add_partition()
To:     Christoph Hellwig <hch@infradead.org>,
        Zhong Jinghua <zhongjinghua@huaweicloud.com>
CC:     <axboe@kernel.dk>, <linux-block@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <yi.zhang@huawei.com>,
        <yukuai3@huawei.com>, <chengzhihao1@huawei.com>,
        <yangerkun@huawei.com>
References: <20230522070615.1485014-1-zhongjinghua@huaweicloud.com>
 <ZG8igEyXrFa4j/gf@infradead.org>
From:   zhongjinghua <zhongjinghua@huawei.com>
In-Reply-To: <ZG8igEyXrFa4j/gf@infradead.org>
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在 2023/5/25 16:55, Christoph Hellwig 写道:
> On Mon, May 22, 2023 at 03:06:15PM +0800, Zhong Jinghua wrote:
>> +	if (p.start < 0 || p.length <= 0 || p.start + p.length < 0)
>> +		return -EINVAL;
>> +
>>   	start = p.start >> SECTOR_SHIFT;
>>   	length = p.length >> SECTOR_SHIFT;
>>   
>> +	/* length may be equal to 0 after right shift */
>> +	if (!length || start + length > get_capacity(bdev->bd_disk))
>> +		return -EINVAL;
> While we're at it, shouldn't these be switched to use
> check_add_overflow?
p.start + p.length < 0 can use  check_add_overflow instead.