drm/amdgpu: Fix potential NULL pointer dereference in atomctrl_get_smc_sclk_range_table

[ Upstream commit 357445e28ff004d7f10967aa93ddb4bffa5c3688 ]

The function atomctrl_get_smc_sclk_range_table() does not check the return
value of smu_atom_get_data_table(). If smu_atom_get_data_table() fails to
retrieve SMU_Info table, it returns NULL which is later dereferenced.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

In practice this should never happen as this code only gets called
on polaris chips and the vbios data table will always be present on
those chips.

Fixes: a23eefa2f461 ("drm/amd/powerplay: enable dpm for baffin.")
Signed-off-by: Ivan Stepchenko <sid@itb.spb.ru>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c
index 165af862d05427ef3d28516f262cd7d54b0848ac..04dbd9f89a45d070dc24749454e1066b5a3d295c 100644 (file)
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c
@@ -1370,6 +1370,8 @@ int atomctrl_get_smc_sclk_range_table(struct pp_hwmgr *hwmgr, struct pp_atom_ctr
                        GetIndexIntoMasterTable(DATA, SMU_Info),
                        &size, &frev, &crev);
 
+       if (!psmu_info)
+               return -EINVAL;
 
        for (i = 0; i < psmu_info->ucSclkEntryNum; i++) {
                table->entry[i].ucVco_setting = psmu_info->asSclkFcwRangeEntry[i].ucVco_setting;