[PATCH v1] OPP: Fix crashing when current OPP has unsupportable voltage

From: Dmitry Osipenko
Date: Sun Jun 23 2019 - 13:51:48 EST


Fix NULL dereference caused by a typo in the code. In particular it
happens when CPU is running on a frequency which has unsupportable voltage
(by regulator) defined in the OPP table and a custom set_opp() callback is
being used. The problem was spotted during of testing of upcoming update
for the NVIDIA Tegra CPUFreq driver.

Cc: stable <stable@xxxxxxxxxxxxxxx>
Fixes: 7e535993fa4f ("OPP: Separate out custom OPP handler specific code")
Reported-by: Marc Dietrich <marvin24@xxxxxx>
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/opp/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 9fda9a0ec016..89ec6aa220cf 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -685,7 +685,7 @@ static int _set_opp_custom(const struct opp_table *opp_table,

data->old_opp.rate = old_freq;
size = sizeof(*old_supply) * opp_table->regulator_count;
- if (IS_ERR(old_supply))
+ if (!old_supply)
memset(data->old_opp.supplies, 0, size);
else
memcpy(data->old_opp.supplies, old_supply, size);
--
2.22.0