The compat_get_timex function in kernel/compat.c in the Linux kernel before 4.16.9 allows local users to obtain sensitive information from kernel memory via adjtimex.
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.16.9
https://www.exploit-db.com/exploits/46208/
https://usn.ubuntu.com/3697-2/
https://usn.ubuntu.com/3697-1/
https://usn.ubuntu.com/3695-2/
https://usn.ubuntu.com/3695-1/
https://github.com/torvalds/linux/commit/0a0b98734479aa5b3c671d5190e86273372cab95
https://bugs.chromium.org/p/project-zero/issues/detail?id=1574