Re: [PATCH 1/2] ALSA: compress: Use memdup_user() rather than duplicating its implementation

[Vinod Koul]

On Sun, Aug 21, 2016 at 09:43:22PM +0200, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> Date: Sun, 21 Aug 2016 21:02:06 +0200
> 
> Reuse existing functionality from memdup_user() instead of keeping
> duplicate source code.
> 
> This issue was detected by using the Coccinelle software.

It usually helps to have Coccinelle script in changelog.

But nevertheless

Acked-by: Vinod Koul <vinod.koul@xxxxxxxxx>

> 
> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
> ---
>  sound/core/compress_offload.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
> 
> diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c
> index 2c49848..583d407 100644
> --- a/sound/core/compress_offload.c
> +++ b/sound/core/compress_offload.c
> @@ -553,13 +553,9 @@ snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
>  		 * we should allow parameter change only when stream has been
>  		 * opened not in other cases
>  		 */
> -		params = kmalloc(sizeof(*params), GFP_KERNEL);
> -		if (!params)
> -			return -ENOMEM;
> -		if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
> -			retval = -EFAULT;
> -			goto out;
> -		}
> +		params = memdup_user((void __user *)arg, sizeof(*params));
> +		if (IS_ERR(params))
> +			return PTR_ERR(params);
>  
>  		retval = snd_compress_check_input(params);
>  		if (retval)
> -- 
> 2.9.3
> 

-- 
~Vinod