FreeBSD -- Potential jail escape vulnerabilities in netmap

Problem Description:
The total size of the user-provided nmreq to nmreq_copyin() was
first computed and then trusted during the copyin. This
time-of-check to time-of-use bug could lead to kernel memory
corruption. [CVE-2022-23084]
A user-provided integer option was passed to nmreq_copyin() without
checking if it would overflow. This insufficient bounds checking
could lead to kernel memory corruption. [CVE-2022-23085]
Impact:
On systems configured to include netmap in their devfs_ruleset, a
privileged process running in a jail can affect the host
environment.