drm/amd/display: Verify Gamma & Degamma LUT sizes in amdgpu_dm_atomic_check

For each CRTC state, check the size of Gamma and Degamma LUTs  so
unexpected and larger sizes wouldn't slip through.

TEST: IGT:kms_color::pipe-invalid-gamma-lut-sizes

v2: fix assignments in if clauses, Mark's email.

Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Mark Yacoub <markyacoub@chromium.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 6fda0df..5dfcd79 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -10245,6 +10245,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
                        dm_old_crtc_state->dsc_force_changed == false)
                        continue;
 
+               ret = amdgpu_dm_verify_lut_sizes(new_crtc_state);
+               if (ret)
+                       goto fail;
+
                if (!new_crtc_state->enable)
                        continue;
 

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
index 22730e5..fcb9c4a 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -617,6 +617,7 @@ void amdgpu_dm_trigger_timing_sync(struct drm_device *dev);
 #define MAX_COLOR_LEGACY_LUT_ENTRIES 256
 
 void amdgpu_dm_init_color_mod(void);
+int amdgpu_dm_verify_lut_sizes(const struct drm_crtc_state *crtc_state);
 int amdgpu_dm_update_crtc_color_mgmt(struct dm_crtc_state *crtc);
 int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc,
                                      struct dc_plane_state *dc_plane_state);

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
index 157fe4e..a022e5b 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
@@ -285,6 +285,37 @@ static int __set_input_tf(struct dc_transfer_func *func,
 }
 
 /**
+ * Verifies that the Degamma and Gamma LUTs attached to the |crtc_state| are of
+ * the expected size.
+ * Returns 0 on success.
+ */
+int amdgpu_dm_verify_lut_sizes(const struct drm_crtc_state *crtc_state)
+{
+       const struct drm_color_lut *lut = NULL;
+       uint32_t size = 0;
+
+       lut = __extract_blob_lut(crtc_state->degamma_lut, &size);
+       if (lut && size != MAX_COLOR_LUT_ENTRIES) {
+               DRM_DEBUG_DRIVER(
+                       "Invalid Degamma LUT size. Should be %u but got %u.\n",
+                       MAX_COLOR_LUT_ENTRIES, size);
+               return -EINVAL;
+       }
+
+       lut = __extract_blob_lut(crtc_state->gamma_lut, &size);
+       if (lut && size != MAX_COLOR_LUT_ENTRIES &&
+           size != MAX_COLOR_LEGACY_LUT_ENTRIES) {
+               DRM_DEBUG_DRIVER(
+                       "Invalid Gamma LUT size. Should be %u (or %u for legacy) but got %u.\n",
+                       MAX_COLOR_LUT_ENTRIES, MAX_COLOR_LEGACY_LUT_ENTRIES,
+                       size);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+/**
  * amdgpu_dm_update_crtc_color_mgmt: Maps DRM color management to DC stream.
  * @crtc: amdgpu_dm crtc state
  *
@@ -317,14 +348,12 @@ int amdgpu_dm_update_crtc_color_mgmt(struct dm_crtc_state *crtc)
        bool is_legacy;
        int r;
 
-       degamma_lut = __extract_blob_lut(crtc->base.degamma_lut, &degamma_size);
-       if (degamma_lut && degamma_size != MAX_COLOR_LUT_ENTRIES)
-               return -EINVAL;
+       r = amdgpu_dm_verify_lut_sizes(&crtc->base);
+       if (r)
+               return r;
 
+       degamma_lut = __extract_blob_lut(crtc->base.degamma_lut, &degamma_size);
        regamma_lut = __extract_blob_lut(crtc->base.gamma_lut, &regamma_size);
-       if (regamma_lut && regamma_size != MAX_COLOR_LUT_ENTRIES &&
-           regamma_size != MAX_COLOR_LEGACY_LUT_ENTRIES)
-               return -EINVAL;
 
        has_degamma =
                degamma_lut && !__is_lut_linear(degamma_lut, degamma_size);