drivers/gpio/gpiolib-cdev.c:795:3: warning: 'strncpy' specified bound 32 equals destination size

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   00e4db51259a5f936fec1424b884f029479d3981
commit: 925ca36913fc7dfee9d0bb7f36d81dd108a7b80f gpiolib: split character device into gpiolib-cdev
date:   7 weeks ago
config: arm64-randconfig-r002-20200811 (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 925ca36913fc7dfee9d0bb7f36d81dd108a7b80f
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 

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

All warnings (new ones prefixed by >>):

   drivers/gpio/gpiolib-cdev.c: In function 'gpio_desc_to_lineinfo':
>> drivers/gpio/gpiolib-cdev.c:795:3: warning: 'strncpy' specified bound 32 equals destination size [-Wstringop-truncation]
     795 |   strncpy(info->name, desc->name, sizeof(info->name));
         |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

vim +/strncpy +795 drivers/gpio/gpiolib-cdev.c

   774	
   775	static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
   776					  struct gpioline_info *info)
   777	{
   778		struct gpio_chip *gc = desc->gdev->chip;
   779		bool ok_for_pinctrl;
   780		unsigned long flags;
   781	
   782		/*
   783		 * This function takes a mutex so we must check this before taking
   784		 * the spinlock.
   785		 *
   786		 * FIXME: find a non-racy way to retrieve this information. Maybe a
   787		 * lock common to both frameworks?
   788		 */
   789		ok_for_pinctrl =
   790			pinctrl_gpio_can_use_line(gc->base + info->line_offset);
   791	
   792		spin_lock_irqsave(&gpio_lock, flags);
   793	
   794		if (desc->name) {
 > 795			strncpy(info->name, desc->name, sizeof(info->name));
   796			info->name[sizeof(info->name) - 1] = '\0';
   797		} else {
   798			info->name[0] = '\0';
   799		}
   800	
   801		if (desc->label) {
   802			strncpy(info->consumer, desc->label, sizeof(info->consumer));
   803			info->consumer[sizeof(info->consumer) - 1] = '\0';
   804		} else {
   805			info->consumer[0] = '\0';
   806		}
   807	
   808		/*
   809		 * Userspace only need to know that the kernel is using this GPIO so
   810		 * it can't use it.
   811		 */
   812		info->flags = 0;
   813		if (test_bit(FLAG_REQUESTED, &desc->flags) ||
   814		    test_bit(FLAG_IS_HOGGED, &desc->flags) ||
   815		    test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
   816		    test_bit(FLAG_EXPORT, &desc->flags) ||
   817		    test_bit(FLAG_SYSFS, &desc->flags) ||
   818		    !ok_for_pinctrl)
   819			info->flags |= GPIOLINE_FLAG_KERNEL;
   820		if (test_bit(FLAG_IS_OUT, &desc->flags))
   821			info->flags |= GPIOLINE_FLAG_IS_OUT;
   822		if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
   823			info->flags |= GPIOLINE_FLAG_ACTIVE_LOW;
   824		if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
   825			info->flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
   826					GPIOLINE_FLAG_IS_OUT);
   827		if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
   828			info->flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
   829					GPIOLINE_FLAG_IS_OUT);
   830		if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
   831			info->flags |= GPIOLINE_FLAG_BIAS_DISABLE;
   832		if (test_bit(FLAG_PULL_DOWN, &desc->flags))
   833			info->flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
   834		if (test_bit(FLAG_PULL_UP, &desc->flags))
   835			info->flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
   836	
   837		spin_unlock_irqrestore(&gpio_lock, flags);
   838	}
   839	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip