An issue was discovered in the Linux kernel before 4.14.11. A double free may be caused by the function allocate_trace_buffer in the file kernel/trace/trace.c.
https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.11
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00037.html
http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00036.html