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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>
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References: <20230522070615.1485014-1-zhongjinghua@huaweicloud.com>
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From:   zhongjinghua <zhongjinghua@huawei.com>
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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.