From 4af9256c89c8dc0b3ada0475debba40ff5303b23 Mon Sep 17 00:00:00 2001 From: Robert Dobrowolski Date: Thu, 24 Mar 2016 03:30:07 -0700 Subject: usb: hcd: out of bounds access in for_each_companion commit e86103a75705c7c530768f4ffaba74cf382910f2 upstream. 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. Signed-off-by: Robert Dobrowolski Acked-by: Alan Stern Signed-off-by: Greg Kroah-Hartman [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings --- drivers/usb/core/hcd-pci.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c index 76be3bae3ff8..8312f9547009 100644 --- a/drivers/usb/core/hcd-pci.c +++ b/drivers/usb/core/hcd-pci.c @@ -70,6 +70,14 @@ static void companion_common(struct pci_dev *pdev, struct usb_hcd *hcd, 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) continue; -- cgit v1.2.3