cf->string = NULL;  
void usb_destroy_configuration(struct usb_device *dev){	int c, i;	if (!dev->config)		return;	if (dev->rawdescriptors) {		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)			kfree(dev->rawdescriptors[i]);		kfree(dev->rawdescriptors);		dev->rawdescriptors = NULL;	}	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {		struct usb_host_config *cf = &dev->config[c];		kfree(cf->string);		cf->string = NULL;		for (i = 0; i < cf->desc.bNumInterfaces; i++) {			if (cf->intf_cache[i])				kref_put(&cf->intf_cache[i]->ref, 					  usb_release_interface_cache);		}	}	kfree(dev->config);	dev->config = NULL;}
4520	/local/tlutelli/issta_data/temp/c/2005_temp/2005/4520/4f62efe67f077db17dad03a1d4c9665000a3eb45/config.c/clean/drivers/usb/core/config.c