[PATCH] HID: wacom: replace sprintf calls with sysfs_emit calls in wacom_sys.c

[PATCH] HID: wacom: replace sprintf calls with sysfs_emit calls in wacom_sys.c

[Nehuen Lian Bova]

Replace 'sprintf' calls with safer 'sysfs_emit' calls in wacom_sys.c, also
include the header '<linux/sysfs.h>'. No functional changes.

Signed-off-by: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>
---
 drivers/hid/wacom_sys.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 628372ab818a..bb51ea4b34f8 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -6,6 +6,7 @@
 #include "wacom_wac.h"
 #include "wacom.h"
 #include <linux/input/mt.h>
+#include <linux/sysfs.h>
 
 #define WAC_MSG_RETRIES		5
 #define WAC_CMD_RETRIES		10
@@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
 	bat_desc->properties = wacom_battery_props;
 	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
 	bat_desc->get_property = wacom_battery_get_property;
-	sprintf(battery->bat_name, "wacom_battery_%ld", n);
+	sysfs_emit(battery->bat_name, "wacom_battery_%ld", n);
 	bat_desc->name = battery->bat_name;
 	bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 	bat_desc->use_for_apm = 0;
@@ -1928,7 +1929,7 @@ static ssize_t wacom_show_remote_mode(struct kobject *kobj,
 	u8 mode;
 
 	mode = wacom->led.groups[index].select;
-	return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
+	return sysfs_emit(buf, "%d\n", mode < 3 ? mode : -1);
 }
 
 #define DEVICE_EKR_ATTR_GROUP(SET_ID)					\
-- 
2.43.0

Re: [PATCH] HID: wacom: replace sprintf calls with sysfs_emit calls in wacom_sys.c

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] HID: wacom: invalid sysfs_emit() call in __wacom_initialize_battery()
--

commit 4c50e84abd55ee59728372c4dfa52c46c6e8c7c7
Author: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>

HID: wacom: replace sprintf calls with sysfs_emit calls in wacom_sys.c

This commit replaces sprintf() calls with sysfs_emit() in drivers/hid/wacom_sys.c
and includes <linux/sysfs.h>.

> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 628372ab818a2..bb51ea4b34f89 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c

[ ... ]

> @@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
>  	bat_desc->properties = wacom_battery_props;
>  	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
>  	bat_desc->get_property = wacom_battery_get_property;
> -	sprintf(battery->bat_name, "wacom_battery_%ld", n);
> +	sysfs_emit(battery->bat_name, "wacom_battery_%ld", n);
>  	bat_desc->name = battery->bat_name;

[Severity: High]
Does using sysfs_emit() here break battery registration?

sysfs_emit() is meant for sysfs show callbacks and requires a page-aligned
buffer:

fs/sysfs/file.c:sysfs_emit() {
	if (WARN(!buf || offset_in_page(buf),
		 "invalid sysfs_emit: buf:%p\n", buf))
		return 0;
}

However, battery->bat_name is a 64-byte array embedded inside struct
wacom_battery:

drivers/hid/wacom.h:
struct wacom_battery {
	struct wacom *wacom;
	struct power_supply_desc bat_desc;
	struct power_supply *battery;
	char bat_name[WACOM_NAME_MAX];
	...
};

When __wacom_initialize_battery() runs during device probe or hotplug,
offset_in_page(battery->bat_name) will be non-zero, causing sysfs_emit() to
trigger a WARN() and return 0 without writing the name, leaving
bat_desc->name empty for devm_power_supply_register(). Furthermore, if it
ever were page-aligned, sysfs_emit() assumes a PAGE_SIZE buffer rather than
sizeof(battery->bat_name).

Should this use snprintf(battery->bat_name, sizeof(battery->bat_name), ...)
instead?

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261101011439.261812-1-nehuenlian.kernel@gmail.com?part=1

[PATCH v2] HID: wacom: replace sprintf calls with safer alternatives

[Nehuen Lian Bova]

Replace sprintf() calls with sysfs_emit() and snprintf() calls in
wacom_sys.c, which are safer and avoid buffer overflows.
Also include the header '<linux/sysfs.h>'

Signed-off-by: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>
---
Changes in v2:
- Use snprintf() instead of sysfs_emit() in __wacom_initialize_battery()
  as suggested by Sashiko bot.
 drivers/hid/wacom_sys.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 628372ab818a..bb5bb9c15f93 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -6,6 +6,7 @@
 #include "wacom_wac.h"
 #include "wacom.h"
 #include <linux/input/mt.h>
+#include <linux/sysfs.h>
 
 #define WAC_MSG_RETRIES		5
 #define WAC_CMD_RETRIES		10
@@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
 	bat_desc->properties = wacom_battery_props;
 	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
 	bat_desc->get_property = wacom_battery_get_property;
-	sprintf(battery->bat_name, "wacom_battery_%ld", n);
+	snprintf(battery->bat_name, "wacom_battery_%ld", n);
 	bat_desc->name = battery->bat_name;
 	bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 	bat_desc->use_for_apm = 0;
@@ -1928,7 +1929,7 @@ static ssize_t wacom_show_remote_mode(struct kobject *kobj,
 	u8 mode;
 
 	mode = wacom->led.groups[index].select;
-	return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
+	return sysfs_emit(buf, "%d\n", mode < 3 ? mode : -1);
 }
 
 #define DEVICE_EKR_ATTR_GROUP(SET_ID)					\
-- 
2.43.0

Re: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [High] HID: wacom: missing size argument in __wacom_initialize_battery() snprintf()
--

commit 3ae99c758bf47da8936a8a4c38001b6a0d39a084
Author: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>

HID: wacom: replace sprintf calls with safer alternatives

This commit replaces sprintf() calls in drivers/hid/wacom_sys.c with
snprintf() in __wacom_initialize_battery() and sysfs_emit() in
wacom_show_remote_mode(), and includes <linux/sysfs.h>.

> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 628372ab818a2..bb5bb9c15f935 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c

[ ... ]

> @@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
>  	bat_desc->properties = wacom_battery_props;
>  	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
>  	bat_desc->get_property = wacom_battery_get_property;
> -	sprintf(battery->bat_name, "wacom_battery_%ld", n);
> +	snprintf(battery->bat_name, "wacom_battery_%ld", n);

[Severity: High]
Is the buffer size argument missing in this snprintf() call in
__wacom_initialize_battery()?

Because snprintf() expects the buffer size as its second parameter, passing
"wacom_battery_%ld" as the second argument and n as the format string pointer
causes a build failure due to incompatible pointer/integer types (or an
invalid pointer dereference when initializing a battery on device probe or
wireless connection).

Should this pass sizeof(battery->bat_name) as the second argument instead:

	snprintf(battery->bat_name, sizeof(battery->bat_name),
		 "wacom_battery_%ld", n);

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261101054830.291749-1-nehuenlian.kernel@gmail.com?part=1

[PATCH v3] HID: wacom: replace sprintf calls with safer alternatives in wacom_sys.c

[Nehuen Lian Bova]

 Replace sprintf() calls with sysfs_emit() and snprintf() calls in
 wacom_sys.c, which are safer and avoid buffer overflows.
 Also include the header '<linux/sysfs.h>'

Signed-off-by: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>
---
Changes in v2:
- Use snprintf() instead of sysfs_emit() in __wacom_initialize_battery()
  as suggested by Sashiko bot.

Changes in v3:
- Pass sizeof(battery->bat_name) to snprintf() as suggested by
  Sashiko bot.
 drivers/hid/wacom_sys.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 628372ab818a..7d9bbcb13ae0 100644
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -6,6 +6,7 @@
 #include "wacom_wac.h"
 #include "wacom.h"
 #include <linux/input/mt.h>
+#include <linux/sysfs.h>
 
 #define WAC_MSG_RETRIES		5
 #define WAC_CMD_RETRIES		10
@@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
 	bat_desc->properties = wacom_battery_props;
 	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
 	bat_desc->get_property = wacom_battery_get_property;
-	sprintf(battery->bat_name, "wacom_battery_%ld", n);
+	snprintf(battery->bat_name, sizeof(battery->bat_name), "wacom_battery_%ld", n);
 	bat_desc->name = battery->bat_name;
 	bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
 	bat_desc->use_for_apm = 0;
@@ -1928,7 +1929,7 @@ static ssize_t wacom_show_remote_mode(struct kobject *kobj,
 	u8 mode;
 
 	mode = wacom->led.groups[index].select;
-	return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
+	return sysfs_emit(buf, "%d\n", mode < 3 ? mode : -1);
 }
 
 #define DEVICE_EKR_ATTR_GROUP(SET_ID)					\
-- 
2.43.0

Re: [PATCH v3] HID: wacom: replace sprintf calls with safer alternatives in wacom_sys.c

[Jason Gerecke]

On Sun, Nov 1, 2026 at 12:18 AM Nehuen Lian Bova
<nehuenlian.kernel@gmail.com> wrote:
>
>  Replace sprintf() calls with sysfs_emit() and snprintf() calls in
>  wacom_sys.c, which are safer and avoid buffer overflows.
>  Also include the header '<linux/sysfs.h>'
>
> Signed-off-by: Nehuen Lian Bova <nehuenlian.kernel@gmail.com>
> ---
> Changes in v2:
> - Use snprintf() instead of sysfs_emit() in __wacom_initialize_battery()
>   as suggested by Sashiko bot.
>
> Changes in v3:
> - Pass sizeof(battery->bat_name) to snprintf() as suggested by
>   Sashiko bot.
>  drivers/hid/wacom_sys.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 628372ab818a..7d9bbcb13ae0 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c
> @@ -6,6 +6,7 @@
>  #include "wacom_wac.h"
>  #include "wacom.h"
>  #include <linux/input/mt.h>
> +#include <linux/sysfs.h>
>
>  #define WAC_MSG_RETRIES                5
>  #define WAC_CMD_RETRIES                10
> @@ -1838,7 +1839,7 @@ static int __wacom_initialize_battery(struct wacom *wacom,
>         bat_desc->properties = wacom_battery_props;
>         bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
>         bat_desc->get_property = wacom_battery_get_property;
> -       sprintf(battery->bat_name, "wacom_battery_%ld", n);
> +       snprintf(battery->bat_name, sizeof(battery->bat_name), "wacom_battery_%ld", n);

If you're going through the effort to use snprintf the string, you
might as well also read its return value to check to check for
truncation (return value greater than or equal to size) and handle
such an error condition appropriately.

Jason (she/they)
---
Now instead of four in the eights place /
you’ve got three, ‘Cause you added one  /
(That is to say, eight) to the two,     /
But you can’t take seven from three,    /
So you look at the sixty-fours....

>         bat_desc->name = battery->bat_name;
>         bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
>         bat_desc->use_for_apm = 0;
> @@ -1928,7 +1929,7 @@ static ssize_t wacom_show_remote_mode(struct kobject *kobj,
>         u8 mode;
>
>         mode = wacom->led.groups[index].select;
> -       return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
> +       return sysfs_emit(buf, "%d\n", mode < 3 ? mode : -1);



>  }
>
>  #define DEVICE_EKR_ATTR_GROUP(SET_ID)                                  \
> --
> 2.43.0
>
>

Re: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives

[kernel test robot]

Hi Nehuen,

kernel test robot noticed the following build errors:

[auto build test ERROR on hid/for-next]
[also build test ERROR on linus/master v7.3 next-20261030]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Nehuen-Lian-Bova/HID-wacom-replace-sprintf-calls-with-safer-alternatives/20261101-024830
base:   https://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git for-next
patch link:    https://lore.kernel.org/r/20261101054830.291749-1-nehuenlian.kernel%40gmail.com
patch subject: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives
config: parisc-randconfig-1001-20261103 (https://download.01.org/0day-ci/archive/20261103/202611031325.X7t40TAw-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 14.4.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261103/202611031325.X7t40TAw-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202611031325.X7t40TAw-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/hid/wacom_sys.c: In function '__wacom_initialize_battery':
>> drivers/hid/wacom_sys.c:1842:37: error: passing argument 2 of 'snprintf' makes integer from pointer without a cast [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                     ^~~~~~~~~~~~~~~~~~~
         |                                     |
         |                                     char *
   In file included from include/linux/kernel.h:32,
                    from include/linux/random.h:7,
                    from include/linux/nodemask.h:94,
                    from include/linux/numa.h:6,
                    from include/linux/cpumask.h:15,
                    from include/linux/smp.h:13,
                    from include/linux/interrupt_rc.h:18,
                    from include/linux/spinlock.h:60,
                    from include/linux/mmzone.h:8,
                    from include/linux/gfp.h:7,
                    from include/linux/slab.h:17,
                    from include/linux/hid.h:19,
                    from drivers/hid/wacom_wac.h:7,
                    from drivers/hid/wacom_sys.c:6:
   include/linux/sprintf.h:13:47: note: expected 'size_t' {aka 'unsigned int'} but argument is of type 'char *'
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                        ~~~~~~~^~~~
>> drivers/hid/wacom_sys.c:1842:58: error: passing argument 3 of 'snprintf' makes pointer from integer without a cast [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                                          ^
         |                                                          |
         |                                                          long unsigned int
   include/linux/sprintf.h:13:65: note: expected 'const char *' but argument is of type 'long unsigned int'
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                                     ~~~~~~~~~~~~^~~


vim +/snprintf +1842 drivers/hid/wacom_sys.c

  1820	
  1821	static int __wacom_initialize_battery(struct wacom *wacom,
  1822					      struct wacom_battery *battery)
  1823	{
  1824		static atomic_t battery_no = ATOMIC_INIT(0);
  1825		struct device *dev = &wacom->hdev->dev;
  1826		struct power_supply_config psy_cfg = { .drv_data = battery, };
  1827		struct power_supply *ps_bat;
  1828		struct power_supply_desc *bat_desc = &battery->bat_desc;
  1829		unsigned long n;
  1830		int error;
  1831	
  1832		if (!devres_open_group(dev, bat_desc, GFP_KERNEL))
  1833			return -ENOMEM;
  1834	
  1835		battery->wacom = wacom;
  1836	
  1837		n = atomic_inc_return(&battery_no) - 1;
  1838	
  1839		bat_desc->properties = wacom_battery_props;
  1840		bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
  1841		bat_desc->get_property = wacom_battery_get_property;
> 1842		snprintf(battery->bat_name, "wacom_battery_%ld", n);
  1843		bat_desc->name = battery->bat_name;
  1844		bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
  1845		bat_desc->use_for_apm = 0;
  1846	
  1847		ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg);
  1848		if (IS_ERR(ps_bat)) {
  1849			error = PTR_ERR(ps_bat);
  1850			goto err;
  1851		}
  1852	
  1853		power_supply_powers(ps_bat, &wacom->hdev->dev);
  1854	
  1855		battery->battery = ps_bat;
  1856	
  1857		devres_close_group(dev, bat_desc);
  1858		return 0;
  1859	
  1860	err:
  1861		devres_release_group(dev, bat_desc);
  1862		return error;
  1863	}
  1864	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives

[kernel test robot]

Hi Nehuen,

kernel test robot noticed the following build errors:

[auto build test ERROR on hid/for-next]
[also build test ERROR on linus/master v7.3 next-20261030]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Nehuen-Lian-Bova/HID-wacom-replace-sprintf-calls-with-safer-alternatives/20261101-024830
base:   https://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git for-next
patch link:    https://lore.kernel.org/r/20261101054830.291749-1-nehuenlian.kernel%40gmail.com
patch subject: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives
config: i386-randconfig-1000-20261103 (https://download.01.org/0day-ci/archive/20261103/202611031735.MAqF2fN1-lkp@intel.com/config)
compiler: clang version 22.1.8 (https://github.com/llvm/llvm-project ca7933e47d3a3451d81e72ac174dcb5aa28b59d1)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261103/202611031735.MAqF2fN1-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202611031735.MAqF2fN1-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/hid/wacom_sys.c:1842:30: error: incompatible pointer to integer conversion passing 'char[18]' to parameter of type '__size_t' (aka 'unsigned int') [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                     ^~~~~~~~~~~~~~~~~~~
   include/linux/sprintf.h:13:47: note: passing argument to parameter 'size' here
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                               ^
>> drivers/hid/wacom_sys.c:1842:51: error: incompatible integer to pointer conversion passing 'unsigned long' to parameter of type 'const char *' [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                                          ^
   include/linux/sprintf.h:13:65: note: passing argument to parameter 'fmt' here
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                                                 ^
   2 errors generated.


vim +1842 drivers/hid/wacom_sys.c

  1820	
  1821	static int __wacom_initialize_battery(struct wacom *wacom,
  1822					      struct wacom_battery *battery)
  1823	{
  1824		static atomic_t battery_no = ATOMIC_INIT(0);
  1825		struct device *dev = &wacom->hdev->dev;
  1826		struct power_supply_config psy_cfg = { .drv_data = battery, };
  1827		struct power_supply *ps_bat;
  1828		struct power_supply_desc *bat_desc = &battery->bat_desc;
  1829		unsigned long n;
  1830		int error;
  1831	
  1832		if (!devres_open_group(dev, bat_desc, GFP_KERNEL))
  1833			return -ENOMEM;
  1834	
  1835		battery->wacom = wacom;
  1836	
  1837		n = atomic_inc_return(&battery_no) - 1;
  1838	
  1839		bat_desc->properties = wacom_battery_props;
  1840		bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
  1841		bat_desc->get_property = wacom_battery_get_property;
> 1842		snprintf(battery->bat_name, "wacom_battery_%ld", n);
  1843		bat_desc->name = battery->bat_name;
  1844		bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
  1845		bat_desc->use_for_apm = 0;
  1846	
  1847		ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg);
  1848		if (IS_ERR(ps_bat)) {
  1849			error = PTR_ERR(ps_bat);
  1850			goto err;
  1851		}
  1852	
  1853		power_supply_powers(ps_bat, &wacom->hdev->dev);
  1854	
  1855		battery->battery = ps_bat;
  1856	
  1857		devres_close_group(dev, bat_desc);
  1858		return 0;
  1859	
  1860	err:
  1861		devres_release_group(dev, bat_desc);
  1862		return error;
  1863	}
  1864	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives

[kernel test robot]

Hi Nehuen,

kernel test robot noticed the following build warnings:

[auto build test WARNING on hid/for-next]
[also build test WARNING on linus/master v7.3 next-20261030]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Nehuen-Lian-Bova/HID-wacom-replace-sprintf-calls-with-safer-alternatives/20261101-024830
base:   https://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git for-next
patch link:    https://lore.kernel.org/r/20261101054830.291749-1-nehuenlian.kernel%40gmail.com
patch subject: [PATCH v2] HID: wacom: replace sprintf calls with safer alternatives
config: nios2-allmodconfig (https://download.01.org/0day-ci/archive/20261103/202611031828.iUFgzaYo-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 11.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261103/202611031828.iUFgzaYo-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202611031828.iUFgzaYo-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/hid/wacom_sys.c: In function '__wacom_initialize_battery':
>> drivers/hid/wacom_sys.c:1842:37: warning: passing argument 2 of 'snprintf' makes integer from pointer without a cast [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                     ^~~~~~~~~~~~~~~~~~~
         |                                     |
         |                                     char *
   In file included from include/linux/kernel.h:32,
                    from include/linux/random.h:7,
                    from include/linux/nodemask.h:94,
                    from include/linux/numa.h:6,
                    from include/linux/cpumask.h:15,
                    from include/linux/smp.h:13,
                    from include/linux/interrupt_rc.h:18,
                    from include/linux/spinlock.h:60,
                    from include/linux/mmzone.h:8,
                    from include/linux/gfp.h:7,
                    from include/linux/slab.h:17,
                    from include/linux/hid.h:19,
                    from drivers/hid/wacom_wac.h:7,
                    from drivers/hid/wacom_sys.c:6:
   include/linux/sprintf.h:13:47: note: expected 'size_t' {aka 'unsigned int'} but argument is of type 'char *'
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                        ~~~~~~~^~~~
>> drivers/hid/wacom_sys.c:1842:58: warning: passing argument 3 of 'snprintf' makes pointer from integer without a cast [-Wint-conversion]
    1842 |         snprintf(battery->bat_name, "wacom_battery_%ld", n);
         |                                                          ^
         |                                                          |
         |                                                          long unsigned int
   In file included from include/linux/kernel.h:32,
                    from include/linux/random.h:7,
                    from include/linux/nodemask.h:94,
                    from include/linux/numa.h:6,
                    from include/linux/cpumask.h:15,
                    from include/linux/smp.h:13,
                    from include/linux/interrupt_rc.h:18,
                    from include/linux/spinlock.h:60,
                    from include/linux/mmzone.h:8,
                    from include/linux/gfp.h:7,
                    from include/linux/slab.h:17,
                    from include/linux/hid.h:19,
                    from drivers/hid/wacom_wac.h:7,
                    from drivers/hid/wacom_sys.c:6:
   include/linux/sprintf.h:13:65: note: expected 'const char *' but argument is of type 'long unsigned int'
      13 | __printf(3, 4) int snprintf(char *buf, size_t size, const char *fmt, ...);
         |                                                     ~~~~~~~~~~~~^~~


vim +/snprintf +1842 drivers/hid/wacom_sys.c

  1820	
  1821	static int __wacom_initialize_battery(struct wacom *wacom,
  1822					      struct wacom_battery *battery)
  1823	{
  1824		static atomic_t battery_no = ATOMIC_INIT(0);
  1825		struct device *dev = &wacom->hdev->dev;
  1826		struct power_supply_config psy_cfg = { .drv_data = battery, };
  1827		struct power_supply *ps_bat;
  1828		struct power_supply_desc *bat_desc = &battery->bat_desc;
  1829		unsigned long n;
  1830		int error;
  1831	
  1832		if (!devres_open_group(dev, bat_desc, GFP_KERNEL))
  1833			return -ENOMEM;
  1834	
  1835		battery->wacom = wacom;
  1836	
  1837		n = atomic_inc_return(&battery_no) - 1;
  1838	
  1839		bat_desc->properties = wacom_battery_props;
  1840		bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
  1841		bat_desc->get_property = wacom_battery_get_property;
> 1842		snprintf(battery->bat_name, "wacom_battery_%ld", n);
  1843		bat_desc->name = battery->bat_name;
  1844		bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
  1845		bat_desc->use_for_apm = 0;
  1846	
  1847		ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg);
  1848		if (IS_ERR(ps_bat)) {
  1849			error = PTR_ERR(ps_bat);
  1850			goto err;
  1851		}
  1852	
  1853		power_supply_powers(ps_bat, &wacom->hdev->dev);
  1854	
  1855		battery->battery = ps_bat;
  1856	
  1857		devres_close_group(dev, bat_desc);
  1858		return 0;
  1859	
  1860	err:
  1861		devres_release_group(dev, bat_desc);
  1862		return error;
  1863	}
  1864	

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki