[PATCH AUTOSEL 6.6 091/139] drm/amd/display: Handle null 'stream_status' in 'planes_changed_for_existing_stream'

[Sasha Levin]

From: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>

[ Upstream commit 8141f21b941710ecebe49220b69822cab3abd23d ]

This commit adds a null check for 'stream_status' in the function
'planes_changed_for_existing_stream'. Previously, the code assumed
'stream_status' could be null, but did not handle the case where it was
actually null. This could lead to a null pointer dereference.

Reported by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_resource.c:3784 planes_changed_for_existing_stream() error: we previously assumed 'stream_status' could be null (see line 3774)

Cc: Tom Chung <chiahsuan.chung@xxxxxxx>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Cc: Roman Li <roman.li@xxxxxxx>
Cc: Alex Hung <alex.hung@xxxxxxx>
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Cc: Harry Wentland <harry.wentland@xxxxxxx>
Cc: Hamza Mahfooz <hamza.mahfooz@xxxxxxx>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
Reviewed-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/display/dc/core/dc_resource.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

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 733e445331ea5..4b34bc9d4e4be 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -2877,8 +2877,10 @@ static bool planes_changed_for_existing_stream(struct dc_state *context,
 		}
 	}
 
-	if (!stream_status)
+	if (!stream_status) {
 		ASSERT(0);
+		return false;
+	}
 
 	for (i = 0; i < set_count; i++)
 		if (set[i].stream == stream)
-- 
2.43.0