[PATCH 2/2] power: supply: fix leaked of_node refs in power_supply_get_battery_info

From: Wen Yang
Date: Tue Apr 16 2019 - 22:42:34 EST


The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./drivers/power/supply/power_supply_core.c:601:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:604:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:632:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:635:2-8: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:653:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:664:3-9: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.
./drivers/power/supply/power_supply_core.c:673:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 595, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: Sebastian Reichel <sre@xxxxxxxxxx>
Cc: linux-pm@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/power/supply/power_supply_core.c | 24 ++++++++++++++++--------
1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index 65c619c..874495c 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -598,10 +598,12 @@ int power_supply_get_battery_info(struct power_supply *psy,

err = of_property_read_string(battery_np, "compatible", &value);
if (err)
- return err;
+ goto out_put_node;

- if (strcmp("simple-battery", value))
- return -ENODEV;
+ if (strcmp("simple-battery", value)) {
+ err = -ENODEV;
+ goto out_put_node;
+ }

/* The property and field names below must correspond to elements
* in enum power_supply_property. For reasoning, see
@@ -629,10 +631,12 @@ int power_supply_get_battery_info(struct power_supply *psy,

len = of_property_count_u32_elems(battery_np, "ocv-capacity-celsius");
if (len < 0 && len != -EINVAL) {
- return len;
+ err = len;
+ goto out_put_node;
} else if (len > POWER_SUPPLY_OCV_TEMP_MAX) {
dev_err(&psy->dev, "Too many temperature values\n");
- return -EINVAL;
+ err = -EINVAL;
+ goto out_put_node;
} else if (len > 0) {
of_property_read_u32_array(battery_np, "ocv-capacity-celsius",
info->ocv_temp, len);
@@ -650,7 +654,8 @@ int power_supply_get_battery_info(struct power_supply *psy,
dev_err(&psy->dev, "failed to get %s\n", propname);
kfree(propname);
power_supply_put_battery_info(psy, info);
- return -EINVAL;
+ err = -EINVAL;
+ goto out_put_node;
}

kfree(propname);
@@ -661,7 +666,8 @@ int power_supply_get_battery_info(struct power_supply *psy,
devm_kcalloc(&psy->dev, tab_len, sizeof(*table), GFP_KERNEL);
if (!info->ocv_table[index]) {
power_supply_put_battery_info(psy, info);
- return -ENOMEM;
+ err = -ENOMEM;
+ goto out_put_node;
}

for (i = 0; i < tab_len; i++) {
@@ -670,7 +676,9 @@ int power_supply_get_battery_info(struct power_supply *psy,
}
}

- return 0;
+out_put_node:
+ of_node_put(battery_np);
+ return err;
}
EXPORT_SYMBOL_GPL(power_supply_get_battery_info);

--
2.9.5