Yama: enable link restrictions when selected

Systems running with Yama enabled expect restrictions on various
potentially dangerous operations that could create backward-compaibility
issues with rare userspace corner-cases. Since 561ec64ae67e ("VFS:
don't do protected {sym,hard}links by default") has disabled VFS link
restrictions by default, enable them for systems using Yama.

Cc: stable@vger.kernel.org # v3.6
Signed-off-by: Kees Cook <keescook@chromium.org>
2 files changed