USB: core: only clean up what we allocated

xairy · gregkh · commit 32fd87b3bbf5 · 2017-12-12T13:04:55.000+01:00
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 &lt;andreyknvl@google.com&gt;
Cc: stable &lt;stable@vger.kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
@@ -764,18 +764,21 @@ 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);
