From: Andrey Konovalov <andreyknvl@google.com>
Date: Mon, 11 Dec 2017 21:48:41 +0000 (+0100)
Subject: USB: core: only clean up what we allocated
X-Git-Tag: v4.15-rc4~14^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=32fd87b3bbf5f7a045546401dfe2894dbbf4d8c3;p=thirdparty%2Flinux.git

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 55b198ba629b3..93b38471754ef 100644
--- 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);