[PATCH 04/15] drm: Check crtc x and y coordinates

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

The crtc x/y panning coordinates are stored as signed integers
internally. The user provides them as unsigned, so we should check
that the user provided values actually fit in the internal datatypes.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_crtc.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index d11763f..3a42c9c 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1774,6 +1774,10 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EINVAL;
 
+	/* For some reason crtc x/y offsets are signed internally. */
+	if (crtc_req->x > INT_MAX || crtc_req->y > INT_MAX)
+		return -ERANGE;
+
 	mutex_lock(&dev->mode_config.mutex);
 	obj = drm_mode_object_find(dev, crtc_req->crtc_id,
 				   DRM_MODE_OBJECT_CRTC);
-- 
1.7.3.4