drm/amd/display: Ensure index calculation will not overflow

[ Upstream commit 8e2734bf44 ]

[WHY & HOW]
Make sure vmid0p72_idx, vnom0p8_idx and vmax0p9_idx calculation will
never overflow and exceess array size.

This fixes 3 OVERRUN and 1 INTEGER_OVERFLOW issues reported by Coverity.

Reviewed-by: Harry Wentland <harry.wentland@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>
This commit is contained in:
Alex Hung 2024-04-24 17:08:04 -06:00 committed by Greg Kroah-Hartman
parent 94b0689984
commit 3dc6bb57da

View File

@ -1453,10 +1453,9 @@ void dcn_bw_update_from_pplib_fclks(
ASSERT(fclks->num_levels);
vmin0p65_idx = 0;
vmid0p72_idx = fclks->num_levels -
(fclks->num_levels > 2 ? 3 : (fclks->num_levels > 1 ? 2 : 1));
vnom0p8_idx = fclks->num_levels - (fclks->num_levels > 1 ? 2 : 1);
vmax0p9_idx = fclks->num_levels - 1;
vmid0p72_idx = fclks->num_levels > 2 ? fclks->num_levels - 3 : 0;
vnom0p8_idx = fclks->num_levels > 1 ? fclks->num_levels - 2 : 0;
vmax0p9_idx = fclks->num_levels > 0 ? fclks->num_levels - 1 : 0;
dc->dcn_soc->fabric_and_dram_bandwidth_vmin0p65 =
32 * (fclks->data[vmin0p65_idx].clocks_in_khz / 1000.0) / 1000.0;