net/sctp/socket.c in the Linux kernel through 4.10.1 does not properly restrict association peel-off operations during certain wait states, which allows local users to cause a denial of service (invalid unlock and double free) via a multithreaded application. NOTE: this vulnerability exists because of an incorrect fix for CVE-2017-5986.
https://github.com/torvalds/linux/commit/dfcb9f4f99f1e9a49e43398a7bfbf56927544af1