to_usb_interface() can only be used on a hid_device whose parent is really
USB; uhid can create devices that identify as being on BUS_USB, but don't
actually have a USB parent.
Fix the use of to_usb_interface() without a hid_is_usb() check.

I have verified that it is currently possible to trigger a kernel splat due
to this bug in an ASAN build, and that this commit fixes the issue.

Fixes: 00e005c952f7 ("hid-asus: check ROG Ally MCU version and warn")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
---
 drivers/hid/hid-asus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index 3f5e96900b67..befa990b3210 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c

@@ -753,7 +753,7 @@ static int asus_kbd_register_leds(struct hid_device *hdev)
 			return ret;
 	}
 
-	if (drvdata->quirks & QUIRK_ROG_ALLY_XPAD) {
+	if ((drvdata->quirks & QUIRK_ROG_ALLY_XPAD) && hid_is_usb(hdev)) {
 		intf = to_usb_interface(hdev->dev.parent);
 		udev = interface_to_usbdev(intf);
 		validate_mcu_fw_version(hdev,

-- 
2.55.0.rc0.799.gd6f94ed593-goog