Re: [PATCH] hwmon: (core) fix resource leak on devm_kcalloc failure

From: Guenter Roeck
Date: Mon Oct 24 2016 - 09:09:42 EST


On 10/23/2016 01:56 PM, Colin King wrote:
From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

If dev_kcalloc fails to allocate hw_dev->groups then the current
exit path is a direct return, causing a leak of resources such
as hwdev and ida is not removed. Fix this by exiting via the
free_hwmon exit path that performs the necessary resource cleanup.

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Good catch! Applied.

Thanks,
Guenter

---
drivers/hwmon/hwmon.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c
index adae684..a74c075 100644
--- a/drivers/hwmon/hwmon.c
+++ b/drivers/hwmon/hwmon.c
@@ -536,8 +536,10 @@ __hwmon_device_register(struct device *dev, const char *name, void *drvdata,

hwdev->groups = devm_kcalloc(dev, ngroups, sizeof(*groups),
GFP_KERNEL);
- if (!hwdev->groups)
- return ERR_PTR(-ENOMEM);
+ if (!hwdev->groups) {
+ err = -ENOMEM;
+ goto free_hwmon;
+ }

attrs = __hwmon_create_attrs(dev, drvdata, chip);
if (IS_ERR(attrs)) {