[PATCH AUTOSEL 5.4 42/74] drm/amd/display: Verify Gamma & Degamma LUT sizes in amdgpu_dm_atomic_check

Sasha Levin
2021-07-06T12:01:37Z

From: Mark Yacoub <markyacoub@chromium.org>

[ Upstream commit 03fc4cf45d30533d54f0f4ebc02aacfa12f52ce2 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 4 ++
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 1 +
.../amd/display/amdgpu_dm/amdgpu_dm_color.c | 41 ++++++++++++++++---
3 files changed, 40 insertions(+), 6 deletions(-)

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 fca466d4806b..11da904fcb7e 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -7407,6 +7407,10 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
old_crtc_state->vrr_enabled == new_crtc_state->vrr_enabled)
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 c8c525a2b505..54163c970e7a 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h
@@ -387,6 +387,7 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
#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 2233d293a707..6acc460a3e98 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c
@@ -277,6 +277,37 @@ static int __set_input_tf(struct dc_transfer_func *func,
return res ? 0 : -ENOMEM;
}

+/**
+ * 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
@@ -311,14 +342,12 @@ 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);
--
2.30.2