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 5e6136d2ed71dbb39563f05f361e5e21d3c9ac7c..c6578b321838e8b1889a7d2246169c36793f012e 100644 (file)
--- a/drivers/usb/core/config.c
+++ b/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);