[PATCH 5.15/6.1] 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: 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 5.15.y and 6.1.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 ++-
 drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

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 04b370e7e732..877acdbb9d8d 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -2817,6 +2817,7 @@ 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);
@@ -2839,7 +2840,7 @@ 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++)
diff --git a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
index 257ab8820c7a..4dcfdb2c013f 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c
@@ -1190,6 +1190,7 @@ static bool dcn21_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);
@@ -1230,7 +1231,7 @@ static bool dcn21_fast_validate_bw(
 			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);
 
 	for (i = 0, pipe_idx = 0; i < dc->res_pool->pipe_count; i++) {
 		struct pipe_ctx *pipe = &context->res_ctx.pipe_ctx[i];
-- 
2.34.1