[Intel-gfx] [PATCH] drm: check user mode flags for validity

[Jesse Barnes]

Requested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
---
 drivers/gpu/drm/drm_crtc.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 792c3e3..72ae33a 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -1318,6 +1318,18 @@ static int drm_crtc_convert_umode(struct drm_display_mode *out,
 	if (in->clock > INT_MAX || in->vrefresh > INT_MAX)
 		return -ERANGE;
 
+	/* Reject modes with invalid h/vsync */
+	if (!(in->flags & (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NHSYNC)))
+		return -EINVAL;
+	if ((in->flags & DRM_MODE_FLAG_PHSYNC) &&
+	    (in->flags & DRM_MODE_FLAG_NHSYNC))
+		return -EINVAL;
+	if (!(in->flags & (DRM_MODE_FLAG_PVSYNC | DRM_MODE_FLAG_NVSYNC)))
+		return -EINVAL;
+	if ((in->flags & DRM_MODE_FLAG_PVSYNC) &&
+	    (in->flags & DRM_MODE_FLAG_NVSYNC))
+		return -EINVAL;
+
 	out->clock = in->clock;
 	out->hdisplay = in->hdisplay;
 	out->hsync_start = in->hsync_start;
-- 
1.7.9.5