From: Johan Hovold <johan@xxxxxxxxxx> commit 4b4f6cecca446abcb686c6e6c451d4f1ec1a7497 upstream. Commit 9d7b18668956 ("HID: magicmouse: add support for Apple Magic Trackpad 2") added a sanity check for an Apple trackpad but returned success instead of -ENODEV when the check failed. This means that the remove callback will dereference the never-initialised driver data pointer when the driver is later unbound (e.g. on USB disconnect). Reported-by: syzbot+ee6f6e2e68886ca256a8@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 9d7b18668956 ("HID: magicmouse: add support for Apple Magic Trackpad 2") Cc: stable@xxxxxxxxxxxxxxx # 4.20 Cc: Claudio Mettler <claudio@xxxxxxxxxxxxxx> Cc: Marek Wyborski <marek.wyborski@xxxxxxxxxxxx> Cc: Sean O'Brien <seobrien@xxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hid/hid-magicmouse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/hid/hid-magicmouse.c +++ b/drivers/hid/hid-magicmouse.c @@ -597,7 +597,7 @@ static int magicmouse_probe(struct hid_d if (id->vendor == USB_VENDOR_ID_APPLE && id->product == USB_DEVICE_ID_APPLE_MAGICTRACKPAD2 && hdev->type != HID_TYPE_USBMOUSE) - return 0; + return -ENODEV; msc = devm_kzalloc(&hdev->dev, sizeof(*msc), GFP_KERNEL); if (msc == NULL) {