From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit ada61aa0b1184a8fda1a89a340c7d6cc4e59aee5 ]
I got memory leak as follows when doing fault injection test:
unreferenced object 0xffff888102740438 (size 8): comm "27", pid 859, jiffies 4295031351 (age 143.992s) hex dump (first 8 bytes): 68 77 6d 6f 6e 30 00 00 hwmon0.. backtrace: [<00000000544b5996>] __kmalloc_track_caller+0x1a6/0x300 [<00000000df0d62b9>] kvasprintf+0xad/0x140 [<00000000d3d2a3da>] kvasprintf_const+0x62/0x190 [<000000005f8f0f29>] kobject_set_name_vargs+0x56/0x140 [<00000000b739e4b9>] dev_set_name+0xb0/0xe0 [<0000000095b69c25>] __hwmon_device_register+0xf19/0x1e50 [hwmon] [<00000000a7e65b52>] hwmon_device_register_with_info+0xcb/0x110 [hwmon] [<000000006f181e86>] devm_hwmon_device_register_with_info+0x85/0x100 [hwmon] [<0000000081bdc567>] tmp421_probe+0x2d2/0x465 [tmp421] [<00000000502cc3f8>] i2c_device_probe+0x4e1/0xbb0 [<00000000f90bda3b>] really_probe+0x285/0xc30 [<000000007eac7b77>] __driver_probe_device+0x35f/0x4f0 [<000000004953d43d>] driver_probe_device+0x4f/0x140 [<000000002ada2d41>] __device_attach_driver+0x24c/0x330 [<00000000b3977977>] bus_for_each_drv+0x15d/0x1e0 [<000000005bf2a8e3>] __device_attach+0x267/0x410
When device_register() returns an error, the name allocated in dev_set_name() will be leaked, the put_device() should be used instead of calling hwmon_dev_release() to give up the device reference, then the name will be freed in kobject_cleanup().
Reported-by: Hulk Robot hulkci@huawei.com Fixes: bab2243ce189 ("hwmon: Introduce hwmon_device_register_with_groups") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Link: https://lore.kernel.org/r/20211012112758.2681084-1-yangyingliang@huawei.com Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Sasha Levin sashal@kernel.org --- 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 652973d83a07e..b1b5c1e97a430 100644 --- a/drivers/hwmon/hwmon.c +++ b/drivers/hwmon/hwmon.c @@ -627,8 +627,10 @@ __hwmon_device_register(struct device *dev, const char *name, void *drvdata, dev_set_drvdata(hdev, drvdata); dev_set_name(hdev, HWMON_ID_FORMAT, id); err = device_register(hdev); - if (err) - goto free_hwmon; + if (err) { + put_device(hdev); + goto ida_remove; + }
if (dev && dev->of_node && chip && chip->ops->read && chip->info[0]->type == hwmon_chip &&