| From 65c4a3a4da123141e469c995b05c8e032466627c Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Thu, 12 Jun 2025 16:06:41 +0800 |
| Subject: drm/amd/display: add null check |
| |
| From: Peichen Huang <PeiChen.Huang@amd.com> |
| |
| [ Upstream commit 158b9201c17fc93ed4253c2f03b77fd2671669a1 ] |
| |
| [WHY] |
| Prevents null pointer dereferences to enhance function robustness |
| |
| [HOW] |
| Adds early null check and return false if invalid. |
| |
| Reviewed-by: Cruise Hung <cruise.hung@amd.com> |
| Signed-off-by: Peichen Huang <PeiChen.Huang@amd.com> |
| Signed-off-by: Ray Wu <ray.wu@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/core/dc.c | 6 ++++-- |
| 1 file changed, 4 insertions(+), 2 deletions(-) |
| |
| diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c |
| index 3dd7e2b6d530..943ebd5c79e3 100644 |
| --- a/drivers/gpu/drm/amd/display/dc/core/dc.c |
| +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c |
| @@ -6394,11 +6394,13 @@ unsigned int dc_get_det_buffer_size_from_state(const struct dc_state *context) |
| */ |
| bool dc_get_host_router_index(const struct dc_link *link, unsigned int *host_router_index) |
| { |
| - struct dc *dc = link->ctx->dc; |
| + struct dc *dc; |
| |
| - if (link->ep_type != DISPLAY_ENDPOINT_USB4_DPIA) |
| + if (!link || !host_router_index || link->ep_type != DISPLAY_ENDPOINT_USB4_DPIA) |
| return false; |
| |
| + dc = link->ctx->dc; |
| + |
| if (link->link_index < dc->lowest_dpia_link_index) |
| return false; |
| |
| -- |
| 2.39.5 |
| |
