[PATCH] amdgpu/pm: prevent array underflow in vega20_odn_edit_dpm_table()

[Dan Carpenter]

In the PP_OD_EDIT_VDDC_CURVE case the "input_index" variable is capped at
2 but not checked for negative values so it results in an out of bounds
read.  This value comes from the user via sysfs.

Fixes: d5bf26539494 ("drm/amd/powerplay: added vega20 overdrive support V3")
Signed-off-by: Dan Carpenter <error27 at gmail.com>
---
 drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c
index 97b3ad369046..b30684c84e20 100644
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/vega20_hwmgr.c
@@ -2961,7 +2961,8 @@ static int vega20_odn_edit_dpm_table(struct pp_hwmgr *hwmgr,
 			data->od8_settings.od8_settings_array;
 	OverDriveTable_t *od_table =
 			&(data->smc_state_table.overdrive_table);
-	int32_t input_index, input_clk, input_vol, i;
+	int32_t input_clk, input_vol, i;
+	uint32_t input_index;
 	int od8_id;
 	int ret;
 
-- 
2.35.1