[PATCH v3 01/13] serial: sandbox: Fix buffer underflow in puts

[Sean Anderson]

On 5/30/22 6:00 AM, Andrew Scull wrote:
> Fix the buffer underflow that would occur if puts is called with length
> of zero.
> 
> Fixes: efa51f2bd64 ("serial: sandbox: Implement puts")
> Cc: Sean Anderson <sean.anderson at seco.com>
> Cc: Simon Glass <sjg at chromium.org>
> ---
>  drivers/serial/sandbox.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/serial/sandbox.c b/drivers/serial/sandbox.c
> index e726e19c46..13b54921c4 100644
> --- a/drivers/serial/sandbox.c
> +++ b/drivers/serial/sandbox.c
> @@ -114,7 +114,7 @@ static ssize_t sandbox_serial_puts(struct udevice *dev, const char *s,
>  	struct sandbox_serial_priv *priv = dev_get_priv(dev);
>  	ssize_t ret;
>  
> -	if (s[len - 1] == '\n')
> +	if (len && s[len - 1] == '\n')
>  		priv->start_of_line = true;
>  
>  	if (sandbox_serial_enabled) {
> 

Reviewed-by: Sean Anderson <sean.anderson at seco.com>