drm/amd/display: Add hpd_source index check for dcn401 link encoder setup

This patch adds a boundary check for the hpd_source index during the
link encoder creation process for all dcn401 ip. The check ensures that the
index is within the valid range of the link_enc_hpd_regs array to
prevent out-of-bounds access.

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: Roman Li <roman.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c
index 46feff9..b425b34 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn401/dcn401_resource.c
@@ -1032,7 +1032,7 @@ static struct link_encoder *dcn401_link_encoder_create(
        struct dcn20_link_encoder *enc20 =
                kzalloc(sizeof(struct dcn20_link_encoder), GFP_KERNEL);
 
-       if (!enc20)
+       if (!enc20 || enc_init_data->hpd_source >= ARRAY_SIZE(link_enc_hpd_regs))
                return NULL;
 
 #undef REG_STRUCT