CVE-2026-64595: HID: hid-lenovo-go: cancel cfg_setup work in hid_go_cfg_remove()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Greg Kroah-Hartman <gregkh@kernel.org>

Description
===========

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

HID: hid-lenovo-go: cancel cfg_setup work in hid_go_cfg_remove()

hid_go_cfg_probe() initialises drvdata.go_cfg_setup and schedules it
to run 2 ms later:

    INIT_DELAYED_WORK(&drvdata.go_cfg_setup, &cfg_setup);
    schedule_delayed_work(&drvdata.go_cfg_setup, msecs_to_jiffies(2));

cfg_setup() dereferences drvdata.hdev to issue MCU command requests.
hid_go_cfg_remove() tears down sysfs and stops the HID device, but
never drains the delayed work.  If the device is unbound within the
2 ms scheduling delay (a probe failure rolling back via remove, or a
fast rmmod after probe), the work fires after hid_destroy_device()
has dropped its reference and released the underlying hdev struct,
leaving cfg_setup() with a stale drvdata.hdev pointer.

Mirror the sibling driver hid-lenovo-go-s.c, whose hid_gos_cfg_remove()
already calls cancel_delayed_work_sync() on its analogous work, and
drain go_cfg_setup at the top of hid_go_cfg_remove().  The cancel
must come before guard(mutex)(&drvdata.cfg_mutex) because cfg_setup()
acquires that mutex; reversing the order would deadlock.

The Linux kernel CVE team has assigned CVE-2026-64595 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 7.1 with commit d69ccfcbc9551988190895bc125a8bf709aa5931 and fixed in 7.1.4 with commit 3e7761f7bf9f0187bb18cf52b5119bdf4940e686
	Issue introduced in 7.1 with commit d69ccfcbc9551988190895bc125a8bf709aa5931 and fixed in 7.2-rc1 with commit 73fde0cbff7d9d618591774a12c23434232752c1

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-64595
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/hid/hid-lenovo-go.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/3e7761f7bf9f0187bb18cf52b5119bdf4940e686
	https://git.kernel.org/stable/c/73fde0cbff7d9d618591774a12c23434232752c1