At xhci removal the USB3 hcd (shared_hcd) is removed before the primary USB2 hcd. Interrupts for port status changes may still occur for USB3 ports after the shared_hcd is freed, causing NULL pointer dereference.
Check if xhci->shared_hcd is still valid before handing USB3 port events Cc: <sta...@vger.kernel.org> Reported-by: Peter Chen <peter.c...@nxp.com> Signed-off-by: Mathias Nyman <mathias.ny...@linux.intel.com> --- drivers/usb/host/xhci-ring.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index f0a99aa..3d314b8 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1552,6 +1552,13 @@ static void handle_port_status(struct xhci_hcd *xhci, goto cleanup; } + /* We might get interrupts after shared_hcd is removed */ + if (port->rhub == &xhci->usb3_rhub && xhci->shared_hcd == NULL) { + xhci_dbg(xhci, "ignore port event for removed USB3 hcd\n"); + bogus_port_status = true; + goto cleanup; + } + hcd = port->rhub->hcd; bus_state = &xhci->bus_state[hcd_index(hcd)]; hcd_portnum = port->hcd_portnum; -- 2.7.4