http://secure45nbquibuw6thmenrfamhobdkkrllgxrtayn4sgmnexremexyd.onion/guides/linux-hardening.html
The above values are compatible with x86, but other architectures
may differ. fs.protected_symlinks=1
fs.protected_hardlinks=1 This only permits symlinks to be followed when outside of a world-writable sticky directory, when the owner of the symlink
and follower match, or when the directory owner matches the symlink's owner. This also prevents hardlinks from being created
by users that do not have read/write access to the source file.