A TOCTOU mismatch in the NFS client code in the Linux kernel before 5.8.3 could be used by local attackers to corrupt memory or possibly have unspecified other impact because a size check is in fs/nfs/nfs4proc.c instead of fs/nfs/nfs4xdr.c, aka CID-b4487b935452.
https://usn.ubuntu.com/4578-1/
https://usn.ubuntu.com/4527-1/
https://usn.ubuntu.com/4525-1/
https://twitter.com/grsecurity/status/1303370421958578179
https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html
https://lists.debian.org/debian-lts-announce/2020/09/msg00025.html
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.8.3
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00042.html
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00035.html
http://lists.opensuse.org/opensuse-security-announce/2020-10/msg00021.html