USB: core: only clean up what we allocated

BugLink: https://bugs.launchpad.net/bugs/1826212

commit 32fd87b3 upstream.

When cleaning up the configurations, make sure we only free the number
of configurations and interfaces that we could have allocated.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/usb/core/config.c

@@ -763,18 +763,21 @@ void usb_destroy_configuration(struct usb_device *dev)
 		return;
 
 	if (dev->rawdescriptors) {
-		for (i = 0; i < dev->descriptor.bNumConfigurations; i++)
+		for (i = 0; i < dev->descriptor.bNumConfigurations &&
+				i < USB_MAXCONFIG; i++)
 			kfree(dev->rawdescriptors[i]);
 
 		kfree(dev->rawdescriptors);
 		dev->rawdescriptors = NULL;
 	}
 
-	for (c = 0; c < dev->descriptor.bNumConfigurations; c++) {
+	for (c = 0; c < dev->descriptor.bNumConfigurations &&
+			c < USB_MAXCONFIG; c++) {
 		struct usb_host_config *cf = &dev->config[c];
 
 		kfree(cf->string);
-		for (i = 0; i < cf->desc.bNumInterfaces; i++) {
+		for (i = 0; i < cf->desc.bNumInterfaces &&
+				i < USB_MAXINTERFACES; i++) {
 			if (cf->intf_cache[i])
 				kref_put(&cf->intf_cache[i]->ref,
 					  usb_release_interface_cache);