[PATCH 03/15] drm: Warn if mode to umode conversion overflows the destination types

[ville.syrj...@linux.intel.com]

From: Ville Syrj?l? <ville.syrj...@linux.intel.com>

When converting from a drm_display_mode to drm_mode_modeinfo, print a
warning if the the timings values don't fit into the __u16 datatype.

Signed-off-by: Ville Syrj?l? <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_crtc.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index bbcecdb..d11763f 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1002,6 +1002,13 @@ EXPORT_SYMBOL(drm_mode_config_cleanup);
 void drm_crtc_convert_to_umode(struct drm_mode_modeinfo *out,
                               struct drm_display_mode *in)
 {
+       WARN(in->hdisplay > USHRT_MAX || in->hsync_start > USHRT_MAX ||
+            in->hsync_end > USHRT_MAX || in->htotal > USHRT_MAX ||
+            in->hskew > USHRT_MAX || in->vdisplay > USHRT_MAX ||
+            in->vsync_start > USHRT_MAX || in->vsync_end > USHRT_MAX ||
+            in->vtotal > USHRT_MAX || in->vscan > USHRT_MAX,
+            "timing values too large for mode info\n");
+
        out->clock = in->clock;
        out->hdisplay = in->hdisplay;
        out->hsync_start = in->hsync_start;
-- 
1.7.3.4