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Subject: Re: [PATCH -next] staging: greybus: camera: Switch to
 memdup_user_nul()
To: Dan Carpenter <dan.carpenter@oracle.com>
CC: <linux-kernel@vger.kernel.org>, <linux-staging@lists.linux.dev>,
	<johan@kernel.org>, <elder@kernel.org>, <gregkh@linuxfoundation.org>
References: <20210331095201.2173793-1-yangyingliang@huawei.com>
 <20210331102414.GL2065@kadam>
From: Yang Yingliang <yangyingliang@huawei.com>
Message-ID: <74cc6ea7-7b03-dea1-ba02-0ad41df29ced@huawei.com>
Date: Thu, 1 Apr 2021 10:41:07 +0800
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Hi,

On 2021/3/31 18:24, Dan Carpenter wrote:
> On Wed, Mar 31, 2021 at 05:52:01PM +0800, Yang Yingliang wrote:
>> Use memdup_user_nul() helper instead of open-coding to
>> simplify the code.
>>
>> Reported-by: Hulk Robot <hulkci@huawei.com>
>> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
>> ---
>>   drivers/staging/greybus/camera.c | 10 ++--------
>>   1 file changed, 2 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/staging/greybus/camera.c b/drivers/staging/greybus/camera.c
>> index b570e13394ac..0f005facffbc 100644
>> --- a/drivers/staging/greybus/camera.c
>> +++ b/drivers/staging/greybus/camera.c
>> @@ -1120,16 +1120,10 @@ static ssize_t gb_camera_debugfs_write(struct file *file,
>>   	if (len > 1024)
>>   		return -EINVAL;
>>   
>> -	kbuf = kmalloc(len + 1, GFP_KERNEL);
>> -	if (!kbuf)
>> +	kbuf = memdup_user_nul(buf, len);
>> +	if (IS_ERR(kbuf))
>>   		return -ENOMEM;
> return PTR_ERR(kbuf);
>
>>   
>> -	if (copy_from_user(kbuf, buf, len)) {
>> -		ret = -EFAULT;
>> -		goto done;
>> -	}
>> -
>> -	kbuf[len] = '\0';
>>   
>     ^^^^^^^^
> Please delete this blank line so there aren't two blank lines in a row.

I will change it and send a v2.

Thanks,

Yang

>
>>   	ret = op->execute(gcam, kbuf, len);
> regards,
> dan carpenter
>
> .