execve thread unsafe
The execve system call doesn't make the thread go single threaded so it's thread unsafe and multiple threads might be running the program loader at the same time. Eeep. Ideally, there should be a staged approach where first all other threads are frozen, but can be resumed in case execve fails and can bail out. Then at the point of no return, terminate all the other threads. Check also if exit and other critical syscalls are protected in this manner.