From: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Tue, 20 Mar 2012 14:46:05 +0000 (+0200)
Subject: drm: Warn if mode to umode conversion overflows the destination types
X-Git-Tag: 2.1b_release~206
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7ed972e883070d693cc6ce4564b2605079ba93cf;p=kernel%2Fkernel-mfld-blackbay.git

drm: Warn if mode to umode conversion overflows the destination types

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 Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index d414775..c1310df 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1052,6 +1052,13 @@ 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;