drm/i915/dsi: be defensive about out of bounds operation byte
Untie the VBT based generic panel driver from the VBT parsing, so that
the two don't have to be updated in lockstep.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/01c71ac89a9db8bc7b8ae0fb05c50a5fae362dc4.1450702954.git.jani.nikula@intel.com
diff --git a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
index c6aea69..9bd9208 100644
--- a/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
+++ b/drivers/gpu/drm/i915/intel_dsi_panel_vbt.c
@@ -232,11 +232,9 @@
typedef const u8 * (*fn_mipi_elem_exec)(struct intel_dsi *intel_dsi,
const u8 *data);
static const fn_mipi_elem_exec exec_elem[] = {
- NULL, /* reserved */
- mipi_exec_send_packet,
- mipi_exec_delay,
- mipi_exec_gpio,
- NULL, /* status read; later */
+ [MIPI_SEQ_ELEM_SEND_PKT] = mipi_exec_send_packet,
+ [MIPI_SEQ_ELEM_DELAY] = mipi_exec_delay,
+ [MIPI_SEQ_ELEM_GPIO] = mipi_exec_gpio,
};
/*
@@ -264,7 +262,6 @@
static void generic_exec_sequence(struct intel_dsi *intel_dsi, const u8 *data)
{
fn_mipi_elem_exec mipi_elem_exec;
- int index;
if (!data)
return;
@@ -277,15 +274,14 @@
/* parse each byte till we reach end of sequence byte - 0x00 */
while (1) {
- index = *data;
- mipi_elem_exec = exec_elem[index];
- if (!mipi_elem_exec) {
- DRM_ERROR("Unsupported MIPI element, skipping sequence execution\n");
+ u8 operation_byte = *data++;
+ if (operation_byte >= ARRAY_SIZE(exec_elem) ||
+ !exec_elem[operation_byte]) {
+ DRM_ERROR("Unsupported MIPI operation byte %u\n",
+ operation_byte);
return;
}
-
- /* goto element payload */
- data++;
+ mipi_elem_exec = exec_elem[operation_byte];
/* execute the element specific rotines */
data = mipi_elem_exec(intel_dsi, data);