Re: [PATCH -next] drm/imagination: Use memdup_user() helper to simplify code

[Frank Binns <Frank.Binns@imgtec.com>]

On Sat, 2024-08-31 at 18:29 +0800, Jinjie Ruan wrote:
> Switching to memdup_user(), which combines kmalloc() and copy_from_user(),
> and it can simplfy code.
> 

Reviewed-by: Frank Binns <frank.binns@imgtec.com>

> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
> ---
>  drivers/gpu/drm/imagination/pvr_job.c | 13 +++----------
>  1 file changed, 3 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/gpu/drm/imagination/pvr_job.c b/drivers/gpu/drm/imagination/pvr_job.c
> index 78c2f3c6dce0..618503a212a7 100644
> --- a/drivers/gpu/drm/imagination/pvr_job.c
> +++ b/drivers/gpu/drm/imagination/pvr_job.c
> @@ -90,20 +90,13 @@ static int pvr_fw_cmd_init(struct pvr_device *pvr_dev, struct pvr_job *job,
>  	void *stream;
>  	int err;
>  
> -	stream = kzalloc(stream_len, GFP_KERNEL);
> -	if (!stream)
> -		return -ENOMEM;
> -
> -	if (copy_from_user(stream, u64_to_user_ptr(stream_userptr), stream_len)) {
> -		err = -EFAULT;
> -		goto err_free_stream;
> -	}
> +	stream = memdup_user(u64_to_user_ptr(stream_userptr), stream_len);
> +	if (IS_ERR(stream))
> +		return PTR_ERR(stream);
>  
>  	err = pvr_job_process_stream(pvr_dev, stream_def, stream, stream_len, job);
>  
> -err_free_stream:
>  	kfree(stream);
> -
>  	return err;
>  }
>