[PATCH AUTOSEL 6.6 51/83] drm/amd/display: added NULL check at start of dc_validate_stream

[Sasha Levin]

From: winstang <winst...@amd.com>

[ Upstream commit 26c56049cc4f1705b498df013949427692a4b0d5 ]

[Why]
prevent invalid memory access

[How]
check if dc and stream are NULL

Co-authored-by: winstang <winst...@amd.com>
Reviewed-by: Alvin Lee <alvin.l...@amd.com>
Acked-by: Zaeem Mohamed <zaeem.moha...@amd.com>
Signed-off-by: winstang <winst...@amd.com>
Tested-by: Daniel Wheeler <daniel.whee...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@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 84923c5400d32..733e445331ea5 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -3927,6 +3927,9 @@ 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