linux-cve-announce - CVE-2022-50616: regulator: core: Use different devices for resource allocation and DT lookup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2025120851-CVE-2022-50616-bef8@gregkh>
Date: Mon,  8 Dec 2025 10:16:53 +0900
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2022-50616: regulator: core: Use different devices for resource allocation and DT lookup

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

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

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

regulator: core: Use different devices for resource allocation and DT lookup

Following by the below discussion, there's the potential UAF issue
between regulator and mfd.
https://lore.kernel.org/all/20221128143601.1698148-1-yangyingliang@huawei.com/

>>From the analysis of Yingliang

CPU A				|CPU B
mt6370_probe()			|
  devm_mfd_add_devices()	|
				|mt6370_regulator_probe()
				|  regulator_register()
				|    //allocate init_data and add it to devres
				|    regulator_of_get_init_data()
i2c_unregister_device()		|
  device_del()			|
    devres_release_all()	|
      // init_data is freed	|
      release_nodes()		|
				|  // using init_data causes UAF
				|  regulator_register()

It's common to use mfd core to create child device for the regulator.
In order to do the DT lookup for init data, the child that registered
the regulator would pass its parent as the parameter. And this causes
init data resource allocated to its parent, not itself. The issue happen
when parent device is going to release and regulator core is still doing
some operation of init data constraint for the regulator of child device.

To fix it, this patch expand 'regulator_register' API to use the
different devices for init data allocation and DT lookup.

The Linux kernel CVE team has assigned CVE-2022-50616 to this issue.


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

	Fixed in 6.0.16 with commit cb29811d989bcb7ea81ca111c4b13878b344e086
	Fixed in 6.1.2 with commit b0f25ca1ff9be7abd1679ae7e59a8f25dbffe67a
	Fixed in 6.2 with commit 8f3cbcd6b440032ebc7f7d48a1689dcc70a4eb98

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-2022-50616
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/intel/int3472/clk_and_regulator.c
	drivers/regulator/core.c
	drivers/regulator/devres.c
	drivers/regulator/of_regulator.c
	drivers/regulator/stm32-vrefbuf.c
	include/linux/regulator/driver.h


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/cb29811d989bcb7ea81ca111c4b13878b344e086
	https://git.kernel.org/stable/c/b0f25ca1ff9be7abd1679ae7e59a8f25dbffe67a
	https://git.kernel.org/stable/c/8f3cbcd6b440032ebc7f7d48a1689dcc70a4eb98