USB: core: only clean up what we allocated

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 55b198ba629b33b4923247736be8fb743286c324..93b38471754ef5f7c2c541a8895752486ac6f652 100644 (file)
--- 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);