Add support for flags in fcntl, socket, socketpair, accept4

[albe19029]

For monitoring process files it is good to know CLOEXEC flag. But for now only part of method support it (inotify_init1, eventfd2, signalfd4, dup3, pipe2, open, openat, open_by_handle_at, pidfd_open,epoll_create1, memfd_create)

But I think this one are very important too:

fcntl (F_DUPFD_CLOEXEC -FD_CLOEXEC, F_SETFD - FD_CLOEXEC)
socket (SOCK_CLOEXEC)
socketpair (SOCK_CLOEXEC)
accept4 (SOCK_CLOEXEC)

Is it possible to add this, as when execve will be called, it is impossible to see which file descriptors should be copy to new process, and which should not.

I also noticed that for some methods flags exists, but in native format, not scap portable PPM_*_CLOEXEC (pidfd_getfd, timerfd_create, userfaultfd)

[Andreagit97]

Hi @albe19029, yes you are right we need to improve the flags management in our syscalls. Your request makes sense! I will add it to the backlog

[albe19029]

Thanks a lot.
Forgot about one more moment:
is it also possible to add open_flags for not only SCAP_FD_FILE_V2 (for now scap_fd_flags_file this flags only added there).