
<   cmd_buf = memdup_user(buffer, count + 1);
---
>   cmd_buf = kmalloc(count + 1, GFP_KERNEL);
>   if (!cmd_buf)
>       return -ENOMEM;
>   if (copy_from_user(cmd_buf, buffer, count)) {
>       kfree(cmd_buf);
>       return -EFAULT;
>   }
>   cmd_buf[count] = '\0';
