CVE-2023-52520: platform/x86: think-lmi: Fix reference leak

CVE-2023-52520: platform/x86: think-lmi: Fix reference leak

[Greg Kroah-Hartman]

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

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

platform/x86: think-lmi: Fix reference leak

If a duplicate attribute is found using kset_find_obj(), a reference
to that attribute is returned which needs to be disposed accordingly
using kobject_put(). Move the setting name validation into a separate
function to allow for this change without having to duplicate the
cleanup code for this setting.
As a side note, a very similar bug was fixed in
commit 7295a996fdab ("platform/x86: dell-sysman: Fix reference leak"),
so it seems that the bug was copied from that driver.

Compile-tested only.

The Linux kernel CVE team has assigned CVE-2023-52520 to this issue.


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

	Issue introduced in 5.14 with commit 1bcad8e510b2 and fixed in 5.15.136 with commit 124cf0ea4b82
	Issue introduced in 5.14 with commit 1bcad8e510b2 and fixed in 6.1.59 with commit af21c9119a37
	Issue introduced in 5.14 with commit 1bcad8e510b2 and fixed in 6.5.8 with commit c6e3023579de
	Issue introduced in 5.14 with commit 1bcad8e510b2 and fixed in 6.6 with commit 528ab3e605ca

Please see https://www.kernel.org or 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-2023-52520
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/think-lmi.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/124cf0ea4b82e1444ec8c7420af4e7db5558c293
	https://git.kernel.org/stable/c/af21c9119a37cecb7ff27ce0c2f3cf721e9d0ec4
	https://git.kernel.org/stable/c/c6e3023579de8d33256771ac0745239029e81106
	https://git.kernel.org/stable/c/528ab3e605cabf2f9c9bd5944d3bfe15f6e94f81