Function do_stat 

fn do_stat(
    r: &Req<'_>,
    dirfd: i32,
    path: &[u8],
    buf: u64,
    flags: i64,
) -> Result<Outcome, i32>

stat/lstat/newfstatat: fill the host’s struct stat in the tracee (144 bytes on x86_64, 128 on aarch64), converted for i386 callers.