Hi,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on usb/usb-testing]
[also build test ERROR on balbi-usb/testing/next peter.chen-usb/ci-for-usb-next v5.9-rc2 next-20200825]
[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]

url:    https://github.com/0day-ci/linux/commits/yanfei-xu-windriver-com/USB-core-limit-access-to-rawdescriptors-which-were-not-allocated/20200826-002050
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: i386-allyesconfig (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce (this is a W=1 build):
        # save the attached .config to linux build tree
        make W=1 ARCH=i386 

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

All errors (new ones prefixed by >>):

   drivers/usb/core/sysfs.c: In function 'read_descriptors':
>> drivers/usb/core/sysfs.c:899:12: error: 'USB_MAXCONFIG' undeclared (first use in this function); did you mean 'USB_DT_CONFIG'?
     899 |    cfgno < USB_MAXCONFIG; ++cfgno) {
         |            ^~~~~~~~~~~~~
         |            USB_DT_CONFIG
   drivers/usb/core/sysfs.c:899:12: note: each undeclared identifier is reported only once for each function it appears in

# https://github.com/0day-ci/linux/commit/dda85cff0852edc4723d1175486a50024ee7289a
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review yanfei-xu-windriver-com/USB-core-limit-access-to-rawdescriptors-which-were-not-allocated/20200826-002050
git checkout dda85cff0852edc4723d1175486a50024ee7289a
vim +899 drivers/usb/core/sysfs.c

   880	
   881	static ssize_t
   882	read_descriptors(struct file *filp, struct kobject *kobj,
   883			struct bin_attribute *attr,
   884			char *buf, loff_t off, size_t count)
   885	{
   886		struct device *dev = kobj_to_dev(kobj);
   887		struct usb_device *udev = to_usb_device(dev);
   888		size_t nleft = count;
   889		size_t srclen, n;
   890		int cfgno;
   891		void *src;
   892	
   893		/* The binary attribute begins with the device descriptor.
   894		 * Following that are the raw descriptor entries for all the
   895		 * configurations (config plus subsidiary descriptors).
   896		 */
   897		for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
   898				nleft > 0 &&
 > 899				cfgno < USB_MAXCONFIG; ++cfgno) {
   900			if (cfgno < 0) {
   901				src = &udev->descriptor;
   902				srclen = sizeof(struct usb_device_descriptor);
   903			} else {
   904				src = udev->rawdescriptors[cfgno];
   905				srclen = __le16_to_cpu(udev->config[cfgno].desc.
   906						wTotalLength);
   907			}
   908			if (off < srclen) {
   909				n = min(nleft, srclen - (size_t) off);
   910				memcpy(buf, src + off, n);
   911				nleft -= n;
   912				buf += n;
   913				off = 0;
   914			} else {
   915				off -= srclen;
   916			}
   917		}
   918		return count - nleft;
   919	}
   920	

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