drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c:1920:7-14: WARNING opportunity for memdup_user

drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c:1920:7-14: WARNING opportunity for memdup_user

[kernel test robot]

Hi Dave,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   78d4f34e2115b517bcbfe7ec0d018bbbb6f9b0b8
commit: 165e8cc3cfec9ef51f3376b0d49b115294f34f3b staging: gpib: Add KBUILD files for GPIB drivers
date:   10 weeks ago
config: x86_64-randconfig-104-20241216 (https://download.01.org/0day-ci/archive/20241216/202412161428.VkrrQFab-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0

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/202412161428.VkrrQFab-lkp@intel.com/

cocci warnings: (new ones prefixed by >>)
>> drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c:1920:7-14: WARNING opportunity for memdup_user

vim +1920 drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c

fce79512a96afac Dave Penkler 2024-09-18  1906  
fce79512a96afac Dave Penkler 2024-09-18  1907  /*
fce79512a96afac Dave Penkler 2024-09-18  1908   *  user space access to write function
fce79512a96afac Dave Penkler 2024-09-18  1909   */
fce79512a96afac Dave Penkler 2024-09-18  1910  
fce79512a96afac Dave Penkler 2024-09-18  1911  static ssize_t skel_write(struct file *file, const char *user_buffer,
fce79512a96afac Dave Penkler 2024-09-18  1912  			  size_t count, loff_t *ppos)
fce79512a96afac Dave Penkler 2024-09-18  1913  {
fce79512a96afac Dave Penkler 2024-09-18  1914  	struct usb_skel *dev;
fce79512a96afac Dave Penkler 2024-09-18  1915  	char *buf;
fce79512a96afac Dave Penkler 2024-09-18  1916  	ssize_t rv;
fce79512a96afac Dave Penkler 2024-09-18  1917  
fce79512a96afac Dave Penkler 2024-09-18  1918  	dev = file->private_data;
fce79512a96afac Dave Penkler 2024-09-18  1919  
fce79512a96afac Dave Penkler 2024-09-18 @1920  	buf = kmalloc(count, GFP_KERNEL);
fce79512a96afac Dave Penkler 2024-09-18  1921  	if (!buf)
fce79512a96afac Dave Penkler 2024-09-18  1922  		return -ENOMEM;
fce79512a96afac Dave Penkler 2024-09-18  1923  
fce79512a96afac Dave Penkler 2024-09-18  1924  	if (copy_from_user(buf, user_buffer, count)) {
fce79512a96afac Dave Penkler 2024-09-18  1925  		kfree(buf);
fce79512a96afac Dave Penkler 2024-09-18  1926  		return -EFAULT;
fce79512a96afac Dave Penkler 2024-09-18  1927  	}
fce79512a96afac Dave Penkler 2024-09-18  1928  
fce79512a96afac Dave Penkler 2024-09-18  1929  	rv = skel_do_write(dev, buf, count);
fce79512a96afac Dave Penkler 2024-09-18  1930  	kfree(buf);
fce79512a96afac Dave Penkler 2024-09-18  1931  	return rv;
fce79512a96afac Dave Penkler 2024-09-18  1932  }
fce79512a96afac Dave Penkler 2024-09-18  1933  #endif
fce79512a96afac Dave Penkler 2024-09-18  1934  

:::::: The code at line 1920 was first introduced by commit
:::::: fce79512a96afacbe297ba3c5c2f7ed34944540d staging: gpib: Add LPVO DIY USB GPIB driver

:::::: TO: Dave Penkler <dpenkler@gmail.com>
:::::: CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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