CVE-2025-68298

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: btusb: mediatek: Avoid btusb_mtk_claim_iso_intf() NULL deref

In btusb_mtk_setup(), we set `btmtk_data->isopkt_intf` to:

usb_ifnum_to_if(data->udev, MTK_ISO_IFNUM)

That function can return NULL in some cases. Even when it returns

NULL, though, we still go on to call btusb_mtk_claim_iso_intf().

As of commit e9087e828827 ("Bluetooth: btusb: mediatek: Add locks for

usb_driver_claim_interface()"), calling btusb_mtk_claim_iso_intf()

when `btmtk_data->isopkt_intf` is NULL will cause a crash because

we'll end up passing a bad pointer to device_lock(). Prior to that

commit we'd pass the NULL pointer directly to

usb_driver_claim_interface() which would detect it and return an

error, which was handled.

Resolve the crash in btusb_mtk_claim_iso_intf() by adding a NULL check

at the start of the function. This makes the code handle a NULL

`btmtk_data->isopkt_intf` the same way it did before the problematic

commit (j

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References