4.19-stable review patch. If anyone has any objections, please let me know.
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From: Mathias Nyman mathias.nyman@linux.intel.com
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: stable@vger.kernel.org Reported-by: Peter Chen peter.chen@nxp.com Tested-by: Jack Pham jackp@codeaurora.org Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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;