[PATCH 4.20 17/92] drm/amd/powerplay: avoid possible buffer overflow

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit fff0d3f7686942bd544b53a48d1b76bd62c46946 ]

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

Signed-off-by: Evan Quan <evan.quan@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Reviewed-by: Likun Gao <Likun.Gao@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 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 3b7fce5d7258..b9e19b0eb905 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/vega20_hwmgr.c
@@ -2244,6 +2244,13 @@ 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 =
@@ -2264,6 +2271,13 @@ 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 =
-- 
2.19.1