USB: prevent buggy hubs from crashing the USB stack

commit d199c96d41d80a567493e12b8e96ea056a1350c1 upstream.

If anyone comes across a high-speed hub that (by mistake or by design)
claims to have no Transaction Translators, plugging a full- or
low-speed device into it will cause the USB stack to crash.  This
patch (as1446) prevents the problem by ignoring such devices, since
the kernel has no way to communicate with them.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Perry Neben <neben@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 27115b45edc51fa4462147077be9b3de36f6142a..0b5561e936c0c976b27c59c3be03f2a243de3b5e 100644 (file)
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2723,6 +2723,11 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
                udev->ttport = hdev->ttport;
        } else if (udev->speed != USB_SPEED_HIGH
                        && hdev->speed == USB_SPEED_HIGH) {
+               if (!hub->tt.hub) {
+                       dev_err(&udev->dev, "parent hub has no TT\n");
+                       retval = -EINVAL;
+                       goto fail;
+               }
                udev->tt = &hub->tt;
                udev->ttport = port1;
        }