The irda_setsockopt function in net/irda/af_irda.c and later in drivers/staging/irda/net/af_irda.c in the Linux kernel before 4.17 allows local users to cause a denial of service (ias_object use-after-free and system crash) or possibly have unspecified other impact via an AF_IRDA socket.
https://lists.debian.org/debian-lts-announce/2018/10/msg00003.html
https://usn.ubuntu.com/3775-1/
https://usn.ubuntu.com/3775-2/
https://usn.ubuntu.com/3776-1/
https://usn.ubuntu.com/3776-2/
https://usn.ubuntu.com/3777-1/
https://usn.ubuntu.com/3777-2/