[PATCH synaptics] Don't allow for scroll distances of 0 (#49965)

[Chase Douglas]

On 05/16/2012 08:30 PM, Peter Hutterer wrote:
> It'll either hang the server or blow up with divisions by 0, whichever one
> comes first.
> 
> X.Org Bug 49965 <http://bugs.freedesktop.org/show_bug.cgi?id=49965>
> 
> Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
> ---
>  src/properties.c |    6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/src/properties.c b/src/properties.c
> index 0cbca09..72ba896 100644
> --- a/src/properties.c
> +++ b/src/properties.c
> @@ -471,6 +471,9 @@ SetProperty(DeviceIntPtr dev, Atom property, XIPropertyValuePtr prop,
>              return BadMatch;
>  
>          dist = (INT32 *) prop->data;
> +        if (dist[0] == 0 || dist[1] == 0)
> +            return BadValue;
> +
>          if (para->scroll_dist_vert != dist[0]) {
>              para->scroll_dist_vert = dist[0];
>              SetScrollValuator(dev, priv->scroll_axis_vert, SCROLL_TYPE_VERTICAL,
> @@ -589,6 +592,9 @@ SetProperty(DeviceIntPtr dev, Atom property, XIPropertyValuePtr prop,
>              return BadMatch;
>  
>          circdist = *(float *) prop->data;
> +        if (circdist == 0)
> +            return BadValue;
> +
>          para->scroll_dist_circ = circdist;
>      }
>      else if (property == prop_circscroll_trigger) {

Makes sense.

Reviewed-by: Chase Douglas <chase.douglas at canonical.com>