CVE-2022-47929

A NULL pointer dereference flaw was found in qdisc_graft in net/sched/sch_api.c in the Linux kernel. This issue may allow a local unprivileged user to trigger a denial of service if the alloc_workqueue function return is not validated in time of failure, resulting in a system crash or leaked internal kernel information.

Mitigation

The mitigation is to disable unprivileged user namespaces by setting user.max_user_namespaces to 0:

# echo "user.max_user_namespaces=0" > /etc/sysctl.d/userns.conf  
# sysctl -p /etc/sysctl.d/userns.conf