usb: hcd: out of bounds access in for_each_companion

On BXT platform Host Controller and Device Controller figure as
same PCI device but with different device function. HCD should
not pass data to Device Controller but only to Host Controllers.
Checking if companion device is Host Controller, otherwise skip.

Cc: <stable@vger.kernel.org>
Signed-off-by: Robert Dobrowolski <robert.dobrowolski@linux.intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Robert Dobrowolski 2016-03-24 03:30:07 -07:00 committed by Greg Kroah-Hartman
parent 1363074667
commit e86103a757
1 changed files with 9 additions and 0 deletions

View File

@ -73,6 +73,15 @@ static void for_each_companion(struct pci_dev *pdev, struct usb_hcd *hcd,
if (companion->bus != pdev->bus ||
PCI_SLOT(companion->devfn) != slot)
continue;
/*
* Companion device should be either UHCI,OHCI or EHCI host
* controller, otherwise skip.
*/
if (companion->class != CL_UHCI && companion->class != CL_OHCI &&
companion->class != CL_EHCI)
continue;
companion_hcd = pci_get_drvdata(companion);
if (!companion_hcd || !companion_hcd->self.root_hub)
continue;