CVE-2023-54107

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: dropping parent refcount after pd_free_fn() is done Some cgroup policies will access parent pd through child pd even after pd_offline_fn() is done. If pd_free_fn() for parent is called before child, then UAF can be triggered. Hence it's better to guarantee the order of pd_free_fn(). Currently refcount of parent blkg is dropped in __blkg_release(), which is before pd_free_fn() is called in blkg_free_work_fn() while blkg_free_work_fn() is called asynchronously. This patch make sure pd_free_fn() called from removing cgroup is ordered by delaying dropping parent refcount after calling pd_free_fn() for child. BTW, pd_free_fn() will also be called from blkcg_deactivate_policy() from deleting device, and following patches will guarantee the order.

The following products are affected by CVE-2023-54107 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2023-54107.

URL	Resource
https://git.kernel.org/stable/c/c7241babf0855d8a6180cd1743ff0ec34de40b4e
https://lore.kernel.org/linux-cve-announce/2025122412-CVE-2023-54107-12ef@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2023-54107
https://www.cve.org/CVERecord?id=CVE-2023-54107