Re: [PATCH 2/2] android/hidhost: Simplify handle_uhid_output

[Luiz Augusto von Dentz <luiz.dentz@gmail.com>]

Hi Szymon,

On Mon, Dec 16, 2013 at 4:37 PM, Szymon Janc <szymon.janc@tieto.com> wrote:
> Make it use VLA for req buffer. This makes function simpler and also
> fix cutting req to 255 bytes (req_len was uint8_t)
> ---
>  android/hidhost.c | 17 +++++------------
>  1 file changed, 5 insertions(+), 12 deletions(-)
>
> diff --git a/android/hidhost.c b/android/hidhost.c
> index 0e0391a..76322af 100644
> --- a/android/hidhost.c
> +++ b/android/hidhost.c
> @@ -156,29 +156,22 @@ static void hid_device_free(struct hid_device *dev)
>  static void handle_uhid_output(struct hid_device *dev,
>                                                 struct uhid_output_req *output)
>  {
> -       int fd, i;
> -       uint8_t *req = NULL;
> -       uint8_t req_size = 0;
> +       int fd;
> +       unsigned int i;
> +       uint8_t req[1 + (output->size / 2)];

Im not a fan of VLA and Ive seem even some static analyzer that would
warn about its use without first checking > 0 and have a check of
upper bond limit, so perhaps just having it set to UHID_DATA_MAX or
dynamically allocate a buffer to match the output MTU size of the
control channel would better imo.



-- 
Luiz Augusto von Dentz