usb: hcd: out of bounds access in for_each_companion

[cascardo/linux.git] / drivers / usb / core / hcd-pci.c

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index f9d42cf..7859d73 100644 (file)
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -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;