[PATCH 5.10] drm/amd/display: Pass non-null to dcn20_validate_apply_pipe_split_flags

[Daniil Dulov]

From: Alex Hung <alex.hung at amd.com>

commit 5559598742fb4538e4c51c48ef70563c49c2af23 upstream.

[WHAT & HOW]
"dcn20_validate_apply_pipe_split_flags" dereferences merge, and thus it
cannot be a null pointer. Let's pass a valid pointer to avoid null
dereference.

This fixes 2 FORWARD_NULL issues reported by Coverity.

Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira at amd.com>
Signed-off-by: Jerry Zuo <jerry.zuo at amd.com>
Signed-off-by: Alex Hung <alex.hung at amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
[ Daniil: Changes to dcn21_fast_validate_bw() were dropped since the function
  is not inplemented in 5.10.y. Also dcn20 and dcn21 were moved from
  drivers/gpu/drm/amd/display/dc to drivers/gpu/drm/amd/display/dc/resource
  since commit 8b8eed05a1c6 ("drm/amd/display: Refactor resource into component
  directory"). The path is changed accordingly to apply the patch on 5.10.y ]
Signed-off-by: Daniil Dulov <d.dulov at aladdin.ru>
---
Backport fix for CVE-2024-49923

 drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
index b4bff3b3d842..029aba780d83 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -2847,6 +2847,7 @@ bool dcn20_fast_validate_bw(
 {
 	bool out = false;
 	int split[MAX_PIPES] = { 0 };
+	bool merge[MAX_PIPES] = { false };
 	int pipe_cnt, i, pipe_idx, vlevel;
 
 	ASSERT(pipes);
@@ -2869,7 +2870,7 @@ bool dcn20_fast_validate_bw(
 	if (vlevel > context->bw_ctx.dml.soc.num_states)
 		goto validate_fail;
 
-	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, NULL);
+	vlevel = dcn20_validate_apply_pipe_split_flags(dc, context, vlevel, split, merge);
 
 	/*initialize pipe_just_split_from to invalid idx*/
 	for (i = 0; i < MAX_PIPES; i++)
-- 
2.34.1