[PATCH 1/1] sound: avoid endless loop

[Simon Glass]

On Mon, 5 Dec 2022 at 02:05, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> 'sound play 1 100000' results in an endless loop on the sandbox.
>
> If the frequency exceeds half the sampling rate, zero out the output
> buffer.
>
> Fixes: 511ed5fdd389 ("SOUND: SAMSUNG: Add I2S driver")
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> ---
>  drivers/sound/sound.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)

Reviewed-by: Simon Glass <sjg at chromium.org>

(nit below)

>
> diff --git a/drivers/sound/sound.c b/drivers/sound/sound.c
> index 041dfdccfe..c0fc50c99d 100644
> --- a/drivers/sound/sound.c
> +++ b/drivers/sound/sound.c
> @@ -15,7 +15,10 @@ void sound_create_square_wave(uint sample_rate, unsigned short *data, int size,
>         const int period = freq ? sample_rate / freq : 0;
>         const int half = period / 2;
>
> -       assert(freq);
> +       if (!half) {
> +               memset(data, 0, size);

'\0'


> +               return;
> +       }
>
>         /* Make sure we don't overflow our buffer */
>         if (size % 2)
> --
> 2.37.2
>