drm/exynos: added validation of edid for vidi connection

If edid of vidi from user is invalid, size calculated from a number
of cea extensions can be wrong. So, validation should be checked.

Changelog v2:
- just code cleanup
  . declare raw_edid only if vidi->connection is enabled.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

diff --git a/drivers/gpu/drm/exynos/exynos_drm_vidi.c b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
index 6d91000c56f94cfa558c624ad76d50abf2e342a8..13ccbd4bcfaa8c863f27d24870101c32166ecb47 100644 (file)
--- a/drivers/gpu/drm/exynos/exynos_drm_vidi.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_vidi.c
@@ -521,7 +521,6 @@ int vidi_connection_ioctl(struct drm_device *drm_dev, void *data,
        struct exynos_drm_manager *manager;
        struct exynos_drm_display_ops *display_ops;
        struct drm_exynos_vidi_connection *vidi = data;
-       struct edid *raw_edid;
        int edid_len;
 
        DRM_DEBUG_KMS("%s\n", __FILE__);
@@ -558,11 +557,11 @@ int vidi_connection_ioctl(struct drm_device *drm_dev, void *data,
        }
 
        if (vidi->connection) {
-               if (!vidi->edid) {
-                       DRM_DEBUG_KMS("edid data is null.\n");
+               struct edid *raw_edid  = (struct edid *)(uint32_t)vidi->edid;
+               if (!drm_edid_is_valid(raw_edid)) {
+                       DRM_DEBUG_KMS("edid data is invalid.\n");
                        return -EINVAL;
                }
-               raw_edid = (struct edid *)(uint32_t)vidi->edid;
                edid_len = (1 + raw_edid->extensions) * EDID_LENGTH;
                ctx->raw_edid = kzalloc(edid_len, GFP_KERNEL);
                if (!ctx->raw_edid) {