[PATCH 2/3] pmbus_core: Fix NULL pointer dereference

From: Naresh Solanki
Date: Tue Jul 25 2023 - 08:50:34 EST


From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>

Pass i2c_client to _pmbus_is_enabled to drop the assumption
that a regulator device is passed in.

This will fix the issue of a NULL pointer dereference when called from
_pmbus_get_flags.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
---
drivers/hwmon/pmbus/pmbus_core.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 42fb7286805b..1f7df36c48a8 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -2745,9 +2745,8 @@ static const struct pmbus_status_category __maybe_unused pmbus_status_flag_map[]
},
};

-static int _pmbus_is_enabled(struct device *dev, u8 page)
+static int _pmbus_is_enabled(struct i2c_client *client, u8 page)
{
- struct i2c_client *client = to_i2c_client(dev->parent);
int ret;

ret = _pmbus_read_byte_data(client, page, PMBUS_OPERATION);
@@ -2758,14 +2757,13 @@ static int _pmbus_is_enabled(struct device *dev, u8 page)
return !!(ret & PB_OPERATION_CONTROL_ON);
}

-static int __maybe_unused pmbus_is_enabled(struct device *dev, u8 page)
+static int __maybe_unused pmbus_is_enabled(struct i2c_client *client, u8 page)
{
- struct i2c_client *client = to_i2c_client(dev->parent);
struct pmbus_data *data = i2c_get_clientdata(client);
int ret;

mutex_lock(&data->update_lock);
- ret = _pmbus_is_enabled(dev, page);
+ ret = _pmbus_is_enabled(client, page);
mutex_unlock(&data->update_lock);

return ret;
@@ -2844,7 +2842,7 @@ static int _pmbus_get_flags(struct pmbus_data *data, u8 page, unsigned int *flag
if (status < 0)
return status;

- if (_pmbus_is_enabled(dev, page)) {
+ if (_pmbus_is_enabled(client, page)) {
if (status & PB_STATUS_OFF) {
*flags |= REGULATOR_ERROR_FAIL;
*event |= REGULATOR_EVENT_FAIL;
--
2.41.0