From: Harry Wentland <[email protected]> [Why & How] The aux_rd_interval array in struct dc_lttpr_caps is declared with MAX_REPEATER_CNT - 1 (7) elements, indexed 0..6. However, the offset parameter passed to dp_get_eq_aux_rd_interval() can be as large as MAX_REPEATER_CNT (8) when a sink reports 8 LTTPR repeaters via DPCD. This leads to an out-of-bounds read of aux_rd_interval[7] when offset is 8.
Fix this by growing aux_rd_interval to MAX_REPEATER_CNT elements to accommodate the full range of valid repeater counts defined by the DP spec. Cc: [email protected] Assisted-by: GitHub Copilot:Claude claude-4-opus Reviewed-by: Alex Hung <[email protected]> Signed-off-by: Harry Wentland <[email protected]> Signed-off-by: Ray Wu <[email protected]> --- drivers/gpu/drm/amd/display/dc/dc_dp_types.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h index 7e5c118b2f20..fbef0dc743ff 100644 --- a/drivers/gpu/drm/amd/display/dc/dc_dp_types.h +++ b/drivers/gpu/drm/amd/display/dc/dc_dp_types.h @@ -1217,7 +1217,7 @@ struct dc_lttpr_caps { union dp_main_link_channel_coding_lttpr_cap main_link_channel_coding; union dp_128b_132b_supported_lttpr_link_rates supported_128b_132b_rates; union dp_alpm_lttpr_cap alpm; - uint8_t aux_rd_interval[MAX_REPEATER_CNT - 1]; + uint8_t aux_rd_interval[MAX_REPEATER_CNT]; uint8_t lttpr_ieee_oui[3]; // Always read from closest LTTPR to host uint8_t lttpr_device_id[6]; // Always read from closest LTTPR to host }; -- 2.43.0
