USB: core: only clean up what we allocated

commit 32fd87b3bbf5f7a045546401dfe2894dbbf4d8c3 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>

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index bd749e78df592c132c502ab8c108f6ad75459916..1a6ccdd5a5fce023452263e777eb350441d31535 100644 (file)
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -768,18 +768,21 @@ 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);