[PATCH v2] power: supply: fix null pointer dereferencing in power_supply_get_battery_info

From: ruanjinjie
Date: Mon Dec 05 2022 - 02:55:17 EST


when kmalloc() fail to allocate memory in kasprintf(), propname
will be NULL, strcmp() called by of_get_property() will cause
null pointer dereference.

So return ENOMEM if kasprintf() return NULL pointer.

Fixes: 3afb50d7125b ("power: supply: core: Add some helpers to use the battery OCV capacity table")
Signed-off-by: ruanjinjie <ruanjinjie@xxxxxxxxxx>
---
v2:
- release resource instead of just returning error number
---
drivers/power/supply/power_supply_core.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index 4b5fb172fa99..afbe9eecfc30 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -750,6 +750,11 @@ int power_supply_get_battery_info(struct power_supply *psy,
int i, tab_len, size;

propname = kasprintf(GFP_KERNEL, "ocv-capacity-table-%d", index);
+ if (!propname) {
+ power_supply_put_battery_info(psy, info);
+ err = -ENOMEM;
+ goto out_put_node;
+ }
list = of_get_property(battery_np, propname, &size);
if (!list || !size) {
dev_err(&psy->dev, "failed to get %s\n", propname);
--
2.25.1