An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458.
https://www.openwall.com/lists/oss-security/2021/01/29/3
https://www.openwall.com/lists/oss-security/2021/01/29/1
https://www.debian.org/security/2021/dsa-4843
https://security.netapp.com/advisory/ntap-20210304-0005/
https://lists.debian.org/debian-lts-announce/2021/03/msg00010.html
https://lists.debian.org/debian-lts-announce/2021/02/msg00018.html
http://www.openwall.com/lists/oss-security/2021/02/01/4