[BACKPORT 4.4.y 25/25] USB: core: only clean up what we allocated

[Arnd Bergmann]

From: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

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@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
(cherry picked from commit 32fd87b3bbf5f7a045546401dfe2894dbbf4d8c3)
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/usb/core/config.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c
index 6a287c81a7be..b8eb289e0b17 100644
--- a/drivers/usb/core/config.c
+++ b/drivers/usb/core/config.c
@@ -734,18 +734,21 @@ 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);
-- 
2.20.0