The ocfs2_setattr function in fs/ocfs2/file.c in the Linux kernel before 4.14.2 allows local users to cause a denial of service (deadlock) via DIO requests.
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.2
https://usn.ubuntu.com/3655-2/
https://usn.ubuntu.com/3655-1/
https://usn.ubuntu.com/3619-2/
https://usn.ubuntu.com/3619-1/
https://usn.ubuntu.com/3617-3/
https://usn.ubuntu.com/3617-2/
https://usn.ubuntu.com/3617-1/
https://github.com/torvalds/linux/commit/28f5a8a7c033cbf3e32277f4cc9c6afd74f05300