Re: [PATCH v2] video/via: Convert to kstrtou8_from_user

[Florian Tobias Schandinat <FlorianSchandinat@gmx.de>]

On 05/04/2012 12:23 AM, Peter Huewe wrote:
> This patch replaces the code for getting an number from a
> userspace buffer by a simple call to kstrou8_from_user.
> This makes it easier to read and less error prone.
> 
> v2:
> removed initialization of reg_val and dropped check if count < 1
> 
> Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

Applied.


Thanks,

Florian Tobias Schandinat

> ---
> @Alexey: Thanks for the review/feedback!
>  drivers/video/via/viafbdev.c |   34 ++++++++++++----------------------
>  1 files changed, 12 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/video/via/viafbdev.c b/drivers/video/via/viafbdev.c
> index a13c258..88bf5ba 100644
> --- a/drivers/video/via/viafbdev.c
> +++ b/drivers/video/via/viafbdev.c
> @@ -1279,17 +1279,12 @@ static int viafb_dfph_proc_open(struct inode *inode, struct file *file)
>  static ssize_t viafb_dfph_proc_write(struct file *file,
>  	const char __user *buffer, size_t count, loff_t *pos)
>  {
> -	char buf[20];
> -	u8 reg_val = 0;
> -	unsigned long length;
> -	if (count < 1)
> -		return -EINVAL;
> -	length = count > 20 ? 20 : count;
> -	if (copy_from_user(&buf[0], buffer, length))
> -		return -EFAULT;
> -	buf[length - 1] = '\0';	/*Ensure end string */
> -	if (kstrtou8(buf, 0, &reg_val) < 0)
> -		return -EINVAL;
> +	int err;
> +	u8 reg_val;
> +	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
> +	if (err)
> +		return err;
> +
>  	viafb_write_reg_mask(CR97, VIACR, reg_val, 0x0f);
>  	return count;
>  }
> @@ -1319,17 +1314,12 @@ static int viafb_dfpl_proc_open(struct inode *inode, struct file *file)
>  static ssize_t viafb_dfpl_proc_write(struct file *file,
>  	const char __user *buffer, size_t count, loff_t *pos)
>  {
> -	char buf[20];
> -	u8 reg_val = 0;
> -	unsigned long length;
> -	if (count < 1)
> -		return -EINVAL;
> -	length = count > 20 ? 20 : count;
> -	if (copy_from_user(&buf[0], buffer, length))
> -		return -EFAULT;
> -	buf[length - 1] = '\0';	/*Ensure end string */
> -	if (kstrtou8(buf, 0, &reg_val) < 0)
> -		return -EINVAL;
> +	int err;
> +	u8 reg_val;
> +	err = kstrtou8_from_user(buffer, count, 0, &reg_val);
> +	if (err)
> +		return err;
> +
>  	viafb_write_reg_mask(CR99, VIACR, reg_val, 0x0f);
>  	return count;
>  }