Re: [PATCH 1/9] drm: Warn about negative sizes when calculating scale factor

On Tue, Jul 26, 2016 at 05:24:42PM +0100, Chris Wilson wrote:

On Tue, Jul 26, 2016 at 07:06:56PM +0300, ville.syrjala@linux.intel.com wrote:

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From: Ville Syrjälä ville.syrjala@linux.intel.com

Passing negative width/hight to scale factor calculations is not legal. Let's WARN if that happens.

Does this get called with user controllable inputs?

User controllable to a degree. width/height can only ever be positive though.

A quick grep leads me to drm_primary_helper_update() which suggests no. Did I miss a potential user controllable WARN->panic?

I just landed in the BUG_ON in intel_sprite.c on account of a typo I made in the user src/crtc coordinate -> drm_rect conversion. Should probably replace the BUG_ON() with WARN_ON() in i915 as well...