From: Harry Wentland <harry.wentland@xxxxxxx> commit 3dfe85fa87b2a26bdbd292b66653bba065cf9941 upstream. A faulty receiver might report an erroneous channel count. We should guard against reading beyond AUDIO_CHANNELS_COUNT as that would overflow the dpcd_pattern_period array. Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx> Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -2822,7 +2822,7 @@ static void dp_test_get_audio_test_data( &dpcd_pattern_type.value, sizeof(dpcd_pattern_type)); - channel_count = dpcd_test_mode.bits.channel_count + 1; + channel_count = min(dpcd_test_mode.bits.channel_count + 1, AUDIO_CHANNELS_COUNT); // read pattern periods for requested channels when sawTooth pattern is requested if (dpcd_pattern_type.value == AUDIO_TEST_PATTERN_SAWTOOTH ||