[PATCH 3.11 22/25] usb: fix cleanup after failure in hub_configure()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

3.11-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Krzysztof Mazur <krzysiek@podlesie.net>

commit d0308d4b6b02597f39fc31a9bddf7bb3faad5622 upstream.

If the hub_configure() fails after setting the hdev->maxchild
the hub->ports might be NULL or point to uninitialized kzallocated
memory causing NULL pointer dereference in hub_quiesce() during cleanup.

Now after such error the hdev->maxchild is set to 0 to avoid cleanup
of uninitialized ports.

Signed-off-by: Krzysztof Mazur <krzysiek@podlesie.net>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/core/hub.c |    1 +
 1 file changed, 1 insertion(+)

--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1568,6 +1568,7 @@ static int hub_configure(struct usb_hub
 	return 0;
 
 fail:
+	hdev->maxchild = 0;
 	dev_err (hub_dev, "config failed, %s (err %d)\n",
 			message, ret);
 	/* hub_disconnect() frees urb and descriptor */