[PATCH] drm/amd/powerplay: avoid possible buffer overflow

[Evan Quan]

Make sure the clock level enforced is within the allowed
ranges.

Change-Id: If69a8512121c0c94818ab698595502e17569d4c7
Signed-off-by: Evan Quan <evan.quan at amd.com>
---
 drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c b/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c
index 8f6097c6a02b..c2061d351d04 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c
@@ -2251,6 +2251,13 @@ static int vega20_force_clock_level(struct pp_hwmgr *hwmgr,
 		soft_min_level = mask ? (ffs(mask) - 1) : 0;
 		soft_max_level = mask ? (fls(mask) - 1) : 0;
 
+		if (soft_max_level >= data->dpm_table.gfx_table.count) {
+			pr_err("Clock level specified %d is over max allowed %d\n",
+					soft_max_level,
+					data->dpm_table.gfx_table.count - 1);
+			return -EINVAL;
+		}
+
 		data->dpm_table.gfx_table.dpm_state.soft_min_level =
 			data->dpm_table.gfx_table.dpm_levels[soft_min_level].value;
 		data->dpm_table.gfx_table.dpm_state.soft_max_level =
@@ -2271,6 +2278,13 @@ static int vega20_force_clock_level(struct pp_hwmgr *hwmgr,
 		soft_min_level = mask ? (ffs(mask) - 1) : 0;
 		soft_max_level = mask ? (fls(mask) - 1) : 0;
 
+		if (soft_max_level >= data->dpm_table.mem_table.count) {
+			pr_err("Clock level specified %d is over max allowed %d\n",
+					soft_max_level,
+					data->dpm_table.mem_table.count - 1);
+			return -EINVAL;
+		}
+
 		data->dpm_table.mem_table.dpm_state.soft_min_level =
 			data->dpm_table.mem_table.dpm_levels[soft_min_level].value;
 		data->dpm_table.mem_table.dpm_state.soft_max_level =
-- 
2.20.1