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 cc3b62f733941722dd5972b73a1a06c9dd93586e..1fbd23922082ae2e83c6d14b599ab28e0efb3fe9 100644 (file)
--- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c
+++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/ppatomctrl.c
@@ -1420,6 +1420,8 @@ 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;