drm/uapi: Validate the mode flags/type
Currently userspace is allowed to feed in any king of garbage in the
high bits of the mode flags/type, as are drivers when probing modes.
Reject any mode with bogus flags/type.
Hopefully this won't break any current userspace...
v2: Split the type and flags checks to separates ifs (Chris)
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jose Abreu <Jose.Abreu@synopsys.com>
Cc: Adam Jackson <ajax@redhat.com>
Cc: Keith Packard <keithp@keithp.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171115154913.23827-1-ville.syrjala@linux.intel.com
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 1a72883..34b5123 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1036,6 +1036,12 @@ EXPORT_SYMBOL(drm_mode_equal_no_clocks_no_stereo);
enum drm_mode_status
drm_mode_validate_basic(const struct drm_display_mode *mode)
{
+ if (mode->type & ~DRM_MODE_TYPE_ALL)
+ return MODE_BAD;
+
+ if (mode->flags & ~DRM_MODE_FLAG_ALL)
+ return MODE_BAD;
+
if ((mode->flags & DRM_MODE_FLAG_3D_MASK) > DRM_MODE_FLAG_3D_MAX)
return MODE_BAD;