Commit b2c2f2df authored by Luca Coelho's avatar Luca Coelho Committed by Suraj Kandpal
Browse files

drm/i915/bios: double check array-boundary in parse_sdvo_lvds_data 



During static analysis, a concern was raised that we may access the
dtd->dtd[] array out of bounds, because we are not checking whether
the index we use is larger than the array.

This should not be a problem as is, because the enumeration that is
used for this index comes from "panel_type", which uses an enumeration
with 4 items.  But if this enumeration is ever changed, it can lead to
hard-to-detect bugs, so better double-check it before using it as an
index to the array.

Signed-off-by: default avatarLuca Coelho <luciano.coelho@intel.com>
Reviewed-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: default avatarSuraj Kandpal <suraj.kandpal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240528112901.476068-2-luciano.coelho@intel.com
parent 45fe957a

drivers/gpu/drm/i915/display/intel_bios.c

+12 −0
Original line number Diff line number Diff line
@@ -1120,6 +1120,18 @@ parse_sdvo_lvds_data(struct drm_i915_private *i915, 
	if (!dtd)

		return;



	/*

	 * This should not happen, as long as the panel_type

	 * enumeration doesn't grow over 4 items.  But if it does, it

	 * could lead to hard-to-detect bugs, so better double-check

	 * it here to be sure.

	 */

	if (index >= ARRAY_SIZE(dtd->dtd)) {

		drm_err(&i915->drm, "index %d is larger than dtd->dtd[4] array\n",

			index);

		return;

	}



	panel_fixed_mode = kzalloc(sizeof(*panel_fixed_mode), GFP_KERNEL);

	if (!panel_fixed_mode)

		return;