CVE-2026-72346: platform/x86: bitland-mifs-wmi: Fix NULL pointer dereference during suspend/resume

CVE-2026-72346: platform/x86: bitland-mifs-wmi: Fix NULL pointer dereference during suspend/resume

[Greg Kroah-Hartman]

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

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

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

platform/x86: bitland-mifs-wmi: Fix NULL pointer dereference during suspend/resume

The driver registers two distinct WMI devices: a control device
(BITLAND_WMI_CONTROL) and an event device (BITLAND_WMI_EVENT). During
the probe phase, the event device handling path returns early before
initializing the platform profile device (data->pp_dev), leaving it
NULL.

However, the PM sleep operations are registered globally for the WMI
driver and are triggered for both devices. When entering suspend, the
event device invokes bitland_mifs_wmi_suspend(), which passes the
uninitialized data->pp_dev (NULL) into laptop_profile_get(). This leads
to a NULL pointer dereference inside dev_get_drvdata(), causing a
kernel Oops and halting the suspend sequence.

Fix this by adding a validity check for data->pp_dev in both the suspend
and resume callbacks, safely skipping profile operations for the event
device.

The Linux kernel CVE team has assigned CVE-2026-72346 to this issue.


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

	Issue introduced in 7.1 with commit dc1ec4fa86b2b8bba2b6122f2b4420217b5bae9e and fixed in 7.1.5 with commit 6f2cb20d8e286218d51754f06ee219d8ce754b18
	Issue introduced in 7.1 with commit dc1ec4fa86b2b8bba2b6122f2b4420217b5bae9e and fixed in 7.2-rc3 with commit d3666875c75eb1bc8090343fa0d6fc8fb7924356

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-2026-72346
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/platform/x86/bitland-mifs-wmi.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/6f2cb20d8e286218d51754f06ee219d8ce754b18
	https://git.kernel.org/stable/c/d3666875c75eb1bc8090343fa0d6fc8fb7924356