CVE-2024-0443

A flaw was found in the blkgs destruction path in block/blk-cgroup.c in the Linux kernel, leading to a cgroup blkio memory leakage problem. When a cgroup is being destroyed, cgroup_rstat_flush() is only called at css_release_work_fn(), which is called when the blkcg reference count reaches 0. This circular dependency will prevent blkcg and some blkgs from being freed after they are made offline. This issue may allow an attacker with a local access to cause system instability, such as an out of memory error.

This flaw affects RHEL 8.6 and above, and RHEL9.2 and above. Released kernel streamers only.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

This flaw can be mitigated with the possible workaround identified below:

• systemd.unified_cgroup_hierarchy=1

or

• cgroup_disable=blkio