4.19-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mathias Nyman <[email protected]> commit 1245374e9b8340fc255fd51b2015173a83050d03 upstream. 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: <[email protected]> Reported-by: Peter Chen <[email protected]> Tested-by: Jack Pham <[email protected]> Signed-off-by: Mathias Nyman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/usb/host/xhci-ring.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -1552,6 +1552,13 @@ static void handle_port_status(struct xh 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;
