usb: xhci: fix uninitialized completion when USB3 port got wrong status

BugLink: https://bugs.launchpad.net/bugs/1805344
Realtek USB3.0 Card Reader [0bda:0328] reports wrong port status on
Cannon lake PCH USB3.1 xHCI [8086:a36d] after resume from S3,
after clear port reset it works fine.

Since this device is registered on USB3 roothub at boot,
when port status reports not superspeed, xhci_get_port_status will call
an uninitialized completion in bus_state[0].
Kernel will hang because of NULL pointer.

Restrict the USB2 resume status check in USB2 roothub to fix hang issue.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(backported from commit 958c0bd86075d4ef1c936998deefe1947e539240)
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Acked-By: AceLan Kao <acelan.kao@canonical.com>
Acked-by: Hui Wang <hui.wang@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 0fb3fec94e047f3ab48f78bd0cb16e3edce04ded..83db2c4757484b71974c45761bbfb08a5b83e7f2 100644 (file)
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -883,7 +883,7 @@ static u32 xhci_get_port_status(struct usb_hcd *hcd,
                        status |= USB_PORT_STAT_SUSPEND;
        }
        if ((raw_port_status & PORT_PLS_MASK) == XDEV_RESUME &&
-               !DEV_SUPERSPEED_ANY(raw_port_status)) {
+               !DEV_SUPERSPEED_ANY(raw_port_status) && hcd->speed < HCD_USB3) {
                if ((raw_port_status & PORT_RESET) ||
                                !(raw_port_status & PORT_PE))
                        return 0xffffffff;

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 43409ae24ac431e05acc82342d7de95d20cd067f..773e0bdf42350810e3a1a04800ee87b3f1290ffb 100644 (file)
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1708,7 +1708,7 @@ static void handle_port_status(struct xhci_hcd *xhci,
         * RExit to a disconnect state).  If so, let the the driver know it's
         * out of the RExit state.
         */
-       if (!DEV_SUPERSPEED_ANY(portsc) &&
+       if (!DEV_SUPERSPEED_ANY(portsc) && hcd->speed < HCD_USB3 &&
                        test_and_clear_bit(faked_port_index,
                                &bus_state->rexit_ports)) {
                complete(&bus_state->rexit_done[faked_port_index]);