HID: wacom: fix problems when device is not a valid USB device

commit 720ac467204a70308bd687927ed475afb904e11b upstream.

The wacom driver accepts devices of more than just USB types, but some
code paths can cause problems if the device being controlled is not a
USB device due to a lack of checking.  Add the needed checks to ensure
that the USB device accesses are only happening on a "real" USB device,
and not one on some other bus.

Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Cc: linux-input@vger.kernel.org
Cc: stable@vger.kernel.org
Tested-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20211201183503.2373082-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index e94ec84..329bb1a 100644 (file)
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -726,7 +726,7 @@ static void wacom_retrieve_hid_descriptor(struct hid_device *hdev,
         * Skip the query for this type and modify defaults based on
         * interface number.
         */
-       if (features->type == WIRELESS) {
+       if (features->type == WIRELESS && intf) {
                if (intf->cur_altsetting->desc.bInterfaceNumber == 0)
                        features->device_type = WACOM_DEVICETYPE_WL_MONITOR;
                else
@@ -2448,6 +2448,9 @@ static void wacom_wireless_work(struct work_struct *work)
 
        wacom_destroy_battery(wacom);
 
+       if (!usbdev)
+               return;
+
        /* Stylus interface */
        hdev1 = usb_get_intfdata(usbdev->config->interface[1]);
        wacom1 = hid_get_drvdata(hdev1);
@@ -2727,8 +2730,6 @@ static void wacom_mode_change_work(struct work_struct *work)
 static int wacom_probe(struct hid_device *hdev,
                const struct hid_device_id *id)
 {
-       struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
-       struct usb_device *dev = interface_to_usbdev(intf);
        struct wacom *wacom;
        struct wacom_wac *wacom_wac;
        struct wacom_features *features;
@@ -2763,8 +2764,14 @@ static int wacom_probe(struct hid_device *hdev,
        wacom_wac->hid_data.inputmode = -1;
        wacom_wac->mode_report = -1;
 
-       wacom->usbdev = dev;
-       wacom->intf = intf;
+       if (hid_is_usb(hdev)) {
+               struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
+               struct usb_device *dev = interface_to_usbdev(intf);
+
+               wacom->usbdev = dev;
+               wacom->intf = intf;
+       }
+
        mutex_init(&wacom->lock);
        INIT_DELAYED_WORK(&wacom->init_work, wacom_init_work);
        INIT_WORK(&wacom->wireless_work, wacom_wireless_work);