CVE-2019-13272: Linux LPE via 'PTRACE_TRACEME'

what is ptrace
ptrace() system call stands for process trace, which provides a way for debuggers such as gdb/strace to control a process (tracee). "debuggers" can be any process that sends a PTRACE_ATTACH/PTRACE_SEIZE, or receives a PTRACE_TRACEME from its child.
several things to notice:
- a tracee's ptrace relationship …