Subject: CVE-2024-43888: mm: list_lru: fix UAF for memory cgroup

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

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

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

mm: list_lru: fix UAF for memory cgroup

The mem_cgroup_from_slab_obj() is supposed to be called under rcu lock or
cgroup_mutex or others which could prevent returned memcg from being
freed.  Fix it by adding missing rcu read lock.

Found by code inspection.

[[email-masked]: only grab rcu lock when necessary, per Vlastimil]
  Link: https://lkml.kernel.org/r/[email-masked]

The Linux kernel CVE team has assigned CVE-2024-43888 to this issue.

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

	Issue introduced in 6.8 with commit 0a97c01cd20b and fixed in 6.10.5 with commit 4589f77c18dd
	Issue introduced in 6.8 with commit 0a97c01cd20b and fixed in 6.11 with commit 5161b48712dc

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-2024-43888
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/list_lru.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/4589f77c18dd98b65f45617b6d1e95313cf6fcab
	https://git.kernel.org/stable/c/5161b48712dcd08ec427c450399d4d1483e21dea