From ec6c32b58e6c4e87760e797c525e99a460c82bcb Mon Sep 17 00:00:00 2001
From: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Date: Fri, 26 Jul 2024 19:31:55 +0530
Subject: [PATCH] drm/amd/display: Handle null 'stream_status' in
 'planes_changed_for_existing_stream'

[ 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@amd.com>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Cc: Roman Li <roman.li@amd.com>
Cc: Alex Hung <alex.hung@amd.com>
Cc: Aurabindo Pillai <aurabindo.pillai@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 786b56e96a816..7462c34793799 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -3662,8 +3662,10 @@ 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)
-- 
2.47.2