CVE-2022-49920

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

netfilter: nf_tables: netlink notifier might race to release objects

commit release path is invoked via call_rcu and it runs lockless to release the objects after rcu grace period. The netlink notifier handler might win race to remove objects that the transaction context is still referencing from the commit release path.

Call rcu_barrier() to ensure pending rcu callbacks run to completion if the list of transactions to be destroyed is not empty.

The bug could happen only when qdisc with child qdiscs like netem or codel being used.

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.

To mitigate this issue, prevent module sch_hfsc from being loaded. Please see https://access.redhat.com/solutions/41278 for how to blacklist a kernel module to prevent it from loading automatically.