[PATCH AUTOSEL 5.15 31/47] drm/amd/display: added NULL check at start of dc_validate_stream

[Sasha Levin]

From: winstang <winstang at amd.com>

[ Upstream commit 26c56049cc4f1705b498df013949427692a4b0d5 ]

[Why]
prevent invalid memory access

[How]
check if dc and stream are NULL

Co-authored-by: winstang <winstang at amd.com>
Reviewed-by: Alvin Lee <alvin.lee2 at amd.com>
Acked-by: Zaeem Mohamed <zaeem.mohamed at amd.com>
Signed-off-by: winstang <winstang at amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index 42432af34db29..df84f3b521e22 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -2872,6 +2872,9 @@ void resource_build_bit_depth_reduction_params(struct dc_stream_state *stream,
 
 enum dc_status dc_validate_stream(struct dc *dc, struct dc_stream_state *stream)
 {
+	if (dc == NULL || stream == NULL)
+		return DC_ERROR_UNEXPECTED;
+
 	struct dc_link *link = stream->link;
 	struct timing_generator *tg = dc->res_pool->timing_generators[0];
 	enum dc_status res = DC_OK;
-- 
2.43.0