[PATCH AUTOSEL 6.1 05/61] drm/amd/pm: Fix negative array index read

From: Sasha Levin
Date: Wed Jul 31 2024 - 21:12:41 EST


From: Jesse Zhang <jesse.zhang@xxxxxxx>

[ Upstream commit c8c19ebf7c0b202a6a2d37a52ca112432723db5f ]

Avoid using the negative values
for clk_idex as an index into an array pptable->DpmDescriptor.

V2: fix clk_index return check (Tim Huang)

Signed-off-by: Jesse Zhang <Jesse.Zhang@xxxxxxx>
Reviewed-by: Tim Huang <Tim.Huang@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c | 27 ++++++++++++++-----
1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c b/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c
index ed2112efc6c68..286f4f9bfa352 100644
--- a/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c
+++ b/drivers/gpu/drm/amd/pm/swsmu/smu11/navi10_ppt.c
@@ -1215,19 +1215,22 @@ static int navi10_get_current_clk_freq_by_table(struct smu_context *smu,
value);
}

-static bool navi10_is_support_fine_grained_dpm(struct smu_context *smu, enum smu_clk_type clk_type)
+static int navi10_is_support_fine_grained_dpm(struct smu_context *smu, enum smu_clk_type clk_type)
{
PPTable_t *pptable = smu->smu_table.driver_pptable;
DpmDescriptor_t *dpm_desc = NULL;
- uint32_t clk_index = 0;
+ int clk_index = 0;

clk_index = smu_cmn_to_asic_specific_index(smu,
CMN2ASIC_MAPPING_CLK,
clk_type);
+ if (clk_index < 0)
+ return clk_index;
+
dpm_desc = &pptable->DpmDescriptor[clk_index];

/* 0 - Fine grained DPM, 1 - Discrete DPM */
- return dpm_desc->SnapToDiscrete == 0;
+ return dpm_desc->SnapToDiscrete == 0 ? 1 : 0;
}

static inline bool navi10_od_feature_is_supported(struct smu_11_0_overdrive_table *od_table, enum SMU_11_0_ODFEATURE_CAP cap)
@@ -1283,7 +1286,11 @@ static int navi10_emit_clk_levels(struct smu_context *smu,
if (ret)
return ret;

- if (!navi10_is_support_fine_grained_dpm(smu, clk_type)) {
+ ret = navi10_is_support_fine_grained_dpm(smu, clk_type);
+ if (ret < 0)
+ return ret;
+
+ if (!ret) {
for (i = 0; i < count; i++) {
ret = smu_v11_0_get_dpm_freq_by_index(smu,
clk_type, i, &value);
@@ -1492,7 +1499,11 @@ static int navi10_print_clk_levels(struct smu_context *smu,
if (ret)
return size;

- if (!navi10_is_support_fine_grained_dpm(smu, clk_type)) {
+ ret = navi10_is_support_fine_grained_dpm(smu, clk_type);
+ if (ret < 0)
+ return ret;
+
+ if (!ret) {
for (i = 0; i < count; i++) {
ret = smu_v11_0_get_dpm_freq_by_index(smu, clk_type, i, &value);
if (ret)
@@ -1661,7 +1672,11 @@ static int navi10_force_clk_levels(struct smu_context *smu,
case SMU_UCLK:
case SMU_FCLK:
/* There is only 2 levels for fine grained DPM */
- if (navi10_is_support_fine_grained_dpm(smu, clk_type)) {
+ ret = navi10_is_support_fine_grained_dpm(smu, clk_type);
+ if (ret < 0)
+ return ret;
+
+ if (ret) {
soft_max_level = (soft_max_level >= 1 ? 1 : 0);
soft_min_level = (soft_min_level >= 1 ? 1 : 0);
}
--
2.43.0