[PATCH] drm/amd/display: Fix null check for pipe_ctx->plane_state in resource_build_scaling_params

[Ma Ke]

Null pointer dereference issue could occur when pipe_ctx->plane_state
is null. The fix adds a check to ensure 'pipe_ctx->plane_state' is not
null before accessing. This prevents a null pointer dereference.

Found by code review.

Cc: sta...@vger.kernel.org
Fixes: 3be5262e353b ("drm/amd/display: Rename more dc_surface stuff to 
plane_state")
Signed-off-by: Ma Ke <mak...@iscas.ac.cn>
---
 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 520a34a42827..88e8ae63a07f 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1452,6 +1452,9 @@ bool resource_build_scaling_params(struct pipe_ctx 
*pipe_ctx)
        struct scaling_taps temp = {0};
        bool res = false;
 
+       if (!plane_state)
+               return false;
+
        DC_LOGGER_INIT(pipe_ctx->stream->ctx->logger);
 
        /* Invalid input */
-- 
2.25.1