From 95ad20ee3c4efbb91f9a4ab08e070aa3697f5879 Mon Sep 17 00:00:00 2001
From: Alex Hung <alex.hung@amd.com>
Date: Mon, 22 Apr 2024 13:52:27 -0600
Subject: [PATCH] drm/amd/display: Skip finding free audio for unknown
 engine_id

[ Upstream commit 1357b2165d9ad94faa4c4a20d5e2ce29c2ff29c3 ]

[WHY]
ENGINE_ID_UNKNOWN = -1 and can not be used as an array index. Plus, it
also means it is uninitialized and does not need free audio.

[HOW]
Skip and return NULL.

This fixes 2 OVERRUN issues reported by Coverity.

Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Alex Hung <alex.hung@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 | 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 8873acfe309c..84923c5400d3 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -2385,6 +2385,9 @@ static struct audio *find_first_free_audio(
 {
 	int i, available_audio_count;
 
+	if (id == ENGINE_ID_UNKNOWN)
+		return NULL;
+
 	available_audio_count = pool->audio_count;
 
 	for (i = 0; i < available_audio_count; i++) {