From 2343e060c73083a29d2d349b14952c9c3d1d453f Mon Sep 17 00:00:00 2001
From: Alan Stern <stern@rowland.harvard.edu>
Date: Wed, 8 Mar 2006 15:14:09 -0500
Subject: [PATCH] --- yaml --- r: 22083 b: refs/heads/master c:
 6aa35675bbc370e5f11baae7e01a9ab255d8030c h: refs/heads/master i:   22081:
 850dd9c4d26068fb3fee96b4dfe4ecad6b687b6f   22079:
 7df66fb98d68861d76b2c582730576de4bb19f41 v: v3

---
 [refs]                       |  2 +-
 trunk/drivers/usb/core/hub.c | 16 ++++++++++------
 2 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 564530f90bfe..11b3e03db39c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 11a223ae3b86b94391774512e5671600367a305c
+refs/heads/master: 6aa35675bbc370e5f11baae7e01a9ab255d8030c
diff --git a/trunk/drivers/usb/core/hub.c b/trunk/drivers/usb/core/hub.c
index 7dd28f8e1cea..8e65f7a237e4 100644
--- a/trunk/drivers/usb/core/hub.c
+++ b/trunk/drivers/usb/core/hub.c
@@ -1179,8 +1179,11 @@ static int choose_configuration(struct usb_device *udev)
 	c = udev->config;
 	num_configs = udev->descriptor.bNumConfigurations;
 	for (i = 0; i < num_configs; (i++, c++)) {
-		struct usb_interface_descriptor	*desc =
-				&c->intf_cache[0]->altsetting->desc;
+		struct usb_interface_descriptor	*desc = NULL;
+
+		/* It's possible that a config has no interfaces! */
+		if (c->desc.bNumInterfaces > 0)
+			desc = &c->intf_cache[0]->altsetting->desc;
 
 		/*
 		 * HP's USB bus-powered keyboard has only one configuration
@@ -1215,7 +1218,8 @@ static int choose_configuration(struct usb_device *udev)
 		/* If the first config's first interface is COMM/2/0xff
 		 * (MSFT RNDIS), rule it out unless Linux has host-side
 		 * RNDIS support. */
-		if (i == 0 && desc->bInterfaceClass == USB_CLASS_COMM
+		if (i == 0 && desc
+				&& desc->bInterfaceClass == USB_CLASS_COMM
 				&& desc->bInterfaceSubClass == 2
 				&& desc->bInterfaceProtocol == 0xff) {
 #ifndef CONFIG_USB_NET_RNDIS
@@ -1231,8 +1235,8 @@ static int choose_configuration(struct usb_device *udev)
 		 * than a vendor-specific driver. */
 		else if (udev->descriptor.bDeviceClass !=
 						USB_CLASS_VENDOR_SPEC &&
-				desc->bInterfaceClass !=
-						USB_CLASS_VENDOR_SPEC) {
+				(!desc || desc->bInterfaceClass !=
+						USB_CLASS_VENDOR_SPEC)) {
 			best = c;
 			break;
 		}
@@ -3024,7 +3028,7 @@ int usb_reset_device(struct usb_device *udev)
 	parent_hub = hdev_to_hub(parent_hdev);
 
 	/* If we're resetting an active hub, take some special actions */
-	if (udev->actconfig &&
+	if (udev->actconfig && udev->actconfig->desc.bNumInterfaces > 0 &&
 			udev->actconfig->interface[0]->dev.driver ==
 				&hub_driver.driver &&
 			(hub = hdev_to_hub(udev)) != NULL) {