linux-cve-announce - CVE-2022-50433: efi: ssdt: Don't free memory if ACPI table was loaded successfully

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: <2025100158-CVE-2022-50433-440b@gregkh>
Date: Wed,  1 Oct 2025 13:42:06 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2022-50433: efi: ssdt: Don't free memory if ACPI table was loaded successfully

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

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

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

efi: ssdt: Don't free memory if ACPI table was loaded successfully

Amadeusz reports KASAN use-after-free errors introduced by commit
3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from
variables"). The problem appears to be that the memory that holds the
new ACPI table is now freed unconditionally, instead of only when the
ACPI core reported a failure to load the table.

So let's fix this, by omitting the kfree() on success.

The Linux kernel CVE team has assigned CVE-2022-50433 to this issue.


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

	Issue introduced in 6.0 with commit 3881ee0b1edce0ece72d24b7c74f46b73bd6dcba and fixed in 6.0.4 with commit 11497fd69cd2282538ec6eb4cda1d16fc061233d
	Issue introduced in 6.0 with commit 3881ee0b1edce0ece72d24b7c74f46b73bd6dcba and fixed in 6.1 with commit 4b017e59f01097f19b938f6dc4dc2c4720701610

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-2022-50433
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/firmware/efi/efi.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/11497fd69cd2282538ec6eb4cda1d16fc061233d
	https://git.kernel.org/stable/c/4b017e59f01097f19b938f6dc4dc2c4720701610