[PATCH] thermal: core: fix memory leak in __thermal_cooling_device_register()

From: Yang Yingliang <yangyingliang@huawei.com>
To: <linux-kernel@vger.kernel.org>, <linux-pm@vger.kernel.org>
Cc: <rafael@kernel.org>, <daniel.lezcano@linaro.org>,
	<amitk@kernel.org>, <rui.zhang@intel.com>
Subject: [PATCH] thermal: core: fix memory leak in __thermal_cooling_device_register()
Date: Wed, 11 May 2022 10:06:05 +0800	[thread overview]
Message-ID: <20220511020605.3096734-1-yangyingliang@huawei.com> (raw)

I got memory leak as follows when doing fault injection test:

unreferenced object 0xffff888010080000 (size 264312):
  comm "182", pid 102533, jiffies 4296434960 (age 10.100s)
  hex dump (first 32 bytes):
    00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00  .....N..........
    ff ff ff ff ff ff ff ff 40 7f 1f b9 ff ff ff ff  ........@.......
  backtrace:
    [<0000000038b2f4fc>] kmalloc_order_trace+0x1d/0x110 mm/slab_common.c:969
    [<00000000ebcb8da5>] __kmalloc+0x373/0x420 include/linux/slab.h:510
    [<0000000084137f13>] thermal_cooling_device_setup_sysfs+0x15d/0x2d0 include/linux/slab.h:586
    [<00000000352b8755>] __thermal_cooling_device_register+0x332/0xa60 drivers/thermal/thermal_core.c:927
    [<00000000fb9f331b>] devm_thermal_of_cooling_device_register+0x6b/0xf0 drivers/thermal/thermal_core.c:1041
    [<000000009b8012d2>] max6650_probe.cold+0x557/0x6aa drivers/hwmon/max6650.c:211
    [<00000000da0b7e04>] i2c_device_probe+0x472/0xac0 drivers/i2c/i2c-core-base.c:561

If device_register() fails, thermal_cooling_device_destroy_sysfs() need be called
to free the memory allocated in thermal_cooling_device_setup_sysfs().

Fixes: 8ea229511e06 ("thermal: Add cooling device's statistics in sysfs")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
---
 drivers/thermal/thermal_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 82654dc8382b..cdc0552e8c42 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -947,6 +947,7 @@ __thermal_cooling_device_register(struct device_node *np,
 	return cdev;
 
 out_kfree_type:
+	thermal_cooling_device_destroy_sysfs(cdev);
 	kfree(cdev->type);
 	put_device(&cdev->device);
 	cdev = NULL;
-- 
2.25.1

