[PATCH AUTOSEL 6.6 13/83] drm/amd/display: Skip updating link encoder for unknown eng_id

Sasha Levin
2024-08-01T00:22:14Z

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

[ Upstream commit efabdce3db9f3d306084c8946983f3d895810a6b ]

This prevents accessing to negative index of link_encoders array.

This fixes an OVERRUN issue reported by Coverity.

Reviewed-by: Rodrigo Siqueira <rodrigo.siqueira@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@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/link/link_factory.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/link/link_factory.c b/drivers/gpu/drm/amd/display/dc/link/link_factory.c
index 2c366866f5700..6fc0cb918b9e5 100644
--- a/drivers/gpu/drm/amd/display/dc/link/link_factory.c
+++ b/drivers/gpu/drm/amd/display/dc/link/link_factory.c
@@ -408,7 +408,7 @@ static void link_destruct(struct dc_link *link)
* the dynamic assignment of link encoders to streams. Virtual links
* are not assigned encoder resources on creation.
*/
- if (link->link_id.id != CONNECTOR_ID_VIRTUAL) {
+ if (link->link_id.id != CONNECTOR_ID_VIRTUAL && link->eng_id != ENGINE_ID_UNKNOWN) {
link->dc->res_pool->link_encoders[link->eng_id - ENGINE_ID_DIGA] = NULL;
link->dc->res_pool->dig_link_enc_count--;
}
--
2.43.0