Subject: CVE-2024-26621: mm: huge_memory: don't force huge page alignment on 32 bit

From: Greg Kroah-Hartman <[email-masked]>

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

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

mm: huge_memory: don't force huge page alignment on 32 bit

commit efa7df3e3bb5 ("mm: align larger anonymous mappings on THP
boundaries") caused two issues [1] [2] reported on 32 bit system or compat
userspace.

It doesn't make too much sense to force huge page alignment on 32 bit
system due to the constrained virtual address space.

[1] https://lore.kernel.org/linux-mm/[email-masked]/
[2] https://lore.kernel.org/linux-mm/[email-masked]/

The Linux kernel CVE team has assigned CVE-2024-26621 to this issue.

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

	Issue introduced in 5.18 with commit 1854bc6e2420 and fixed in 6.1.81 with commit 87632bc9ecff
	Issue introduced in 5.18 with commit 1854bc6e2420 and fixed in 6.6.46 with commit 6ea9aa8d97e6
	Issue introduced in 5.18 with commit 1854bc6e2420 and fixed in 6.7.6 with commit 7432376c9133
	Issue introduced in 5.18 with commit 1854bc6e2420 and fixed in 6.8 with commit 4ef9ad19e176

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-2024-26621
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:
	mm/huge_memory.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/87632bc9ecff5ded93433bc0fca428019bdd1cfe
	https://git.kernel.org/stable/c/6ea9aa8d97e6563676094cb35755884173269555
	https://git.kernel.org/stable/c/7432376c913381c5f24d373a87ff629bbde94b47
	https://git.kernel.org/stable/c/4ef9ad19e17676b9ef071309bc62020e2373705d