Re: [PATCH v2 2/2] hwmon: Add "label" attribute

From: Dan Carpenter
Date: Mon Jan 10 2022 - 01:45:24 EST

Hi Paul,

url: https://github.com/0day-ci/linux/commits/Paul-Cercueil/hwmon-Add-label-attribute-v2/20220105-231930
base: https://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git hwmon-next
config: i386-randconfig-m021-20220105 (https://download.01.org/0day-ci/archive/20220108/202201081730.TlHZabuC-lkp@xxxxxxxxx/config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

smatch warnings:
drivers/hwmon/hwmon.c:851 __hwmon_device_register() error: uninitialized symbol 'hdev'.
drivers/hwmon/hwmon.c:854 __hwmon_device_register() warn: possible memory leak of 'hwdev'

vim +/hdev +851 drivers/hwmon/hwmon.c

d560168b5d0fb4 Guenter Roeck 2015-08-26 745 static struct device *
d560168b5d0fb4 Guenter Roeck 2015-08-26 746 __hwmon_device_register(struct device *dev, const char *name, void *drvdata,
d560168b5d0fb4 Guenter Roeck 2015-08-26 747 const struct hwmon_chip_info *chip,
bab2243ce18978 Guenter Roeck 2013-07-06 748 const struct attribute_group **groups)
1236441f38b6a9 Mark M. Hoffman 2005-07-15 749 {
bab2243ce18978 Guenter Roeck 2013-07-06 750 struct hwmon_device *hwdev;
57dab49995d01d Paul Cercueil 2022-01-05 751 const char *label;
d560168b5d0fb4 Guenter Roeck 2015-08-26 752 struct device *hdev;
44e3ad882bb268 Akinobu Mita 2020-05-04 753 int i, err, id;
ded2b666156130 Mark M. Hoffman 2006-03-05 754
74d3b6419772e4 Guenter Roeck 2017-01-27 755 /* Complain about invalid characters in hwmon name attribute */
648cd48c9e566f Guenter Roeck 2014-02-28 756 if (name && (!strlen(name) || strpbrk(name, "-* \t\n")))
74d3b6419772e4 Guenter Roeck 2017-01-27 757 dev_warn(dev,
74d3b6419772e4 Guenter Roeck 2017-01-27 758 "hwmon: '%s' is not a valid name attribute, please fix\n",
74d3b6419772e4 Guenter Roeck 2017-01-27 759 name);
648cd48c9e566f Guenter Roeck 2014-02-28 760
4ca5f468cc2a0b Jonathan Cameron 2011-10-31 761 id = ida_simple_get(&hwmon_ida, 0, 0, GFP_KERNEL);
4ca5f468cc2a0b Jonathan Cameron 2011-10-31 762 if (id < 0)
4ca5f468cc2a0b Jonathan Cameron 2011-10-31 763 return ERR_PTR(id);
1236441f38b6a9 Mark M. Hoffman 2005-07-15 764
bab2243ce18978 Guenter Roeck 2013-07-06 765 hwdev = kzalloc(sizeof(*hwdev), GFP_KERNEL);
bab2243ce18978 Guenter Roeck 2013-07-06 766 if (hwdev == NULL) {
bab2243ce18978 Guenter Roeck 2013-07-06 767 err = -ENOMEM;
bab2243ce18978 Guenter Roeck 2013-07-06 768 goto ida_remove;
bab2243ce18978 Guenter Roeck 2013-07-06 769 }
1236441f38b6a9 Mark M. Hoffman 2005-07-15 770
57dab49995d01d Paul Cercueil 2022-01-05 771 if (device_property_present(dev, "label")) {
57dab49995d01d Paul Cercueil 2022-01-05 772 err = device_property_read_string(dev, "label", &label);
57dab49995d01d Paul Cercueil 2022-01-05 773 if (err < 0)
57dab49995d01d Paul Cercueil 2022-01-05 774 goto free_hwmon;

"hwdev" not freed on this goto path and "hdev" is uninitialized. Sort
of related bugs.

57dab49995d01d Paul Cercueil 2022-01-05 775
57dab49995d01d Paul Cercueil 2022-01-05 776 hwdev->label = kstrdup(label, GFP_KERNEL);
57dab49995d01d Paul Cercueil 2022-01-05 777 if (hwdev->label == NULL) {
57dab49995d01d Paul Cercueil 2022-01-05 778 err = -ENOMEM;
57dab49995d01d Paul Cercueil 2022-01-05 779 goto free_hwmon;
57dab49995d01d Paul Cercueil 2022-01-05 780 }
57dab49995d01d Paul Cercueil 2022-01-05 781 }
57dab49995d01d Paul Cercueil 2022-01-05 782
d560168b5d0fb4 Guenter Roeck 2015-08-26 783 hdev = &hwdev->dev;
d560168b5d0fb4 Guenter Roeck 2015-08-26 784
239552f495b91f Guenter Roeck 2016-10-16 785 if (chip) {
d560168b5d0fb4 Guenter Roeck 2015-08-26 786 struct attribute **attrs;
b2a4cc3a060da0 Guenter Roeck 2016-10-16 787 int ngroups = 2; /* terminating NULL plus &hwdev->groups */
d560168b5d0fb4 Guenter Roeck 2015-08-26 788
d560168b5d0fb4 Guenter Roeck 2015-08-26 789 if (groups)
d560168b5d0fb4 Guenter Roeck 2015-08-26 790 for (i = 0; groups[i]; i++)
d560168b5d0fb4 Guenter Roeck 2015-08-26 791 ngroups++;
d560168b5d0fb4 Guenter Roeck 2015-08-26 792
3bf8bdcf3bada7 Guenter Roeck 2020-01-16 793 hwdev->groups = kcalloc(ngroups, sizeof(*groups), GFP_KERNEL);
38d8ed65092ed2 Colin Ian King 2016-10-23 794 if (!hwdev->groups) {
38d8ed65092ed2 Colin Ian King 2016-10-23 795 err = -ENOMEM;
38d8ed65092ed2 Colin Ian King 2016-10-23 796 goto free_hwmon;
38d8ed65092ed2 Colin Ian King 2016-10-23 797 }
d560168b5d0fb4 Guenter Roeck 2015-08-26 798
3bf8bdcf3bada7 Guenter Roeck 2020-01-16 799 attrs = __hwmon_create_attrs(drvdata, chip);
d560168b5d0fb4 Guenter Roeck 2015-08-26 800 if (IS_ERR(attrs)) {
d560168b5d0fb4 Guenter Roeck 2015-08-26 801 err = PTR_ERR(attrs);
d560168b5d0fb4 Guenter Roeck 2015-08-26 802 goto free_hwmon;
d560168b5d0fb4 Guenter Roeck 2015-08-26 803 }
d560168b5d0fb4 Guenter Roeck 2015-08-26 804
d560168b5d0fb4 Guenter Roeck 2015-08-26 805 hwdev->group.attrs = attrs;
d560168b5d0fb4 Guenter Roeck 2015-08-26 806 ngroups = 0;
d560168b5d0fb4 Guenter Roeck 2015-08-26 807 hwdev->groups[ngroups++] = &hwdev->group;
d560168b5d0fb4 Guenter Roeck 2015-08-26 808
d560168b5d0fb4 Guenter Roeck 2015-08-26 809 if (groups) {
d560168b5d0fb4 Guenter Roeck 2015-08-26 810 for (i = 0; groups[i]; i++)
d560168b5d0fb4 Guenter Roeck 2015-08-26 811 hwdev->groups[ngroups++] = groups[i];
d560168b5d0fb4 Guenter Roeck 2015-08-26 812 }
d560168b5d0fb4 Guenter Roeck 2015-08-26 813
d560168b5d0fb4 Guenter Roeck 2015-08-26 814 hdev->groups = hwdev->groups;
d560168b5d0fb4 Guenter Roeck 2015-08-26 815 } else {
d560168b5d0fb4 Guenter Roeck 2015-08-26 816 hdev->groups = groups;
d560168b5d0fb4 Guenter Roeck 2015-08-26 817 }
d560168b5d0fb4 Guenter Roeck 2015-08-26 818
bab2243ce18978 Guenter Roeck 2013-07-06 819 hwdev->name = name;
d560168b5d0fb4 Guenter Roeck 2015-08-26 820 hdev->class = &hwmon_class;
d560168b5d0fb4 Guenter Roeck 2015-08-26 821 hdev->parent = dev;
d560168b5d0fb4 Guenter Roeck 2015-08-26 822 hdev->of_node = dev ? dev->of_node : NULL;
d560168b5d0fb4 Guenter Roeck 2015-08-26 823 hwdev->chip = chip;
d560168b5d0fb4 Guenter Roeck 2015-08-26 824 dev_set_drvdata(hdev, drvdata);
d560168b5d0fb4 Guenter Roeck 2015-08-26 825 dev_set_name(hdev, HWMON_ID_FORMAT, id);
d560168b5d0fb4 Guenter Roeck 2015-08-26 826 err = device_register(hdev);
ada61aa0b1184a Yang Yingliang 2021-10-12 827 if (err) {
ada61aa0b1184a Yang Yingliang 2021-10-12 828 put_device(hdev);
ada61aa0b1184a Yang Yingliang 2021-10-12 829 goto ida_remove;
ada61aa0b1184a Yang Yingliang 2021-10-12 830 }
d560168b5d0fb4 Guenter Roeck 2015-08-26 831
1597b374af2226 Guenter Roeck 2020-05-28 832 INIT_LIST_HEAD(&hwdev->tzdata);
1597b374af2226 Guenter Roeck 2020-05-28 833
c41dd48e21fae3 Eduardo Valentin 2019-05-29 834 if (dev && dev->of_node && chip && chip->ops->read &&
d560168b5d0fb4 Guenter Roeck 2015-08-26 835 chip->info[0]->type == hwmon_chip &&
d560168b5d0fb4 Guenter Roeck 2015-08-26 836 (chip->info[0]->config[0] & HWMON_C_REGISTER_TZ)) {
44e3ad882bb268 Akinobu Mita 2020-05-04 837 err = hwmon_thermal_register_sensors(hdev);
74e3512731bd5c Dmitry Osipenko 2018-10-24 838 if (err) {
74e3512731bd5c Dmitry Osipenko 2018-10-24 839 device_unregister(hdev);
792eac18431967 Guenter Roeck 2019-06-06 840 /*
44e3ad882bb268 Akinobu Mita 2020-05-04 841 * Don't worry about hwdev; hwmon_dev_release(), called
44e3ad882bb268 Akinobu Mita 2020-05-04 842 * from device_unregister(), will free it.
792eac18431967 Guenter Roeck 2019-06-06 843 */
74e3512731bd5c Dmitry Osipenko 2018-10-24 844 goto ida_remove;
74e3512731bd5c Dmitry Osipenko 2018-10-24 845 }
47c332deb8e89f Linus Walleij 2017-12-05 846 }
bab2243ce18978 Guenter Roeck 2013-07-06 847
d560168b5d0fb4 Guenter Roeck 2015-08-26 848 return hdev;
bab2243ce18978 Guenter Roeck 2013-07-06 849
d560168b5d0fb4 Guenter Roeck 2015-08-26 850 free_hwmon:
3bf8bdcf3bada7 Guenter Roeck 2020-01-16 @851 hwmon_dev_release(hdev);
bab2243ce18978 Guenter Roeck 2013-07-06 852 ida_remove:
4ca5f468cc2a0b Jonathan Cameron 2011-10-31 853 ida_simple_remove(&hwmon_ida, id);
bab2243ce18978 Guenter Roeck 2013-07-06 @854 return ERR_PTR(err);
bab2243ce18978 Guenter Roeck 2013-07-06 855 }

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