Race condition in the tty_ioctl function in drivers/tty/tty_io.c in the Linux kernel through 4.4.1 allows local users to obtain sensitive information from kernel memory or cause a denial of service (use-after-free and system crash) by making a TIOCGETD ioctl call during processing of a TIOCSETD ioctl call. http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-0723