1. 50+% of NO_PIE use is fixed by adding -fPIC to INTERNALLIB and other
build-only utility libraries.
2. Another 40% is fixed by generating _pic.a variants of various libraries.
3. Some of the NO_PIE use is a bit absurd as it is disabling PIE (and ASLR)
where it never would work anyhow, such as csu or loader. This suggests
there may be better ways of adding support to the tree. Many of these
cases can be fixed such that -fPIE will work but there is really no
reason to have it in those cases.
4. Some of the uses are working around hacks done to some Makefiles that are
really building libraries but have been using bsd.prog.mk because the code
is cleaner. Had they been using bsd.lib.mk then NO_PIE would not have
been needed.
We likely do want to enable PIE by default (opt-out) for non-tree consumers
(such as ports). For in-tree though we probably want to only enable PIE
(opt-in) for common attack targets such as remote service daemons and setuid
utilities. This is also a great performance compromise since ASLR is expected
to reduce performance. As such it does not make sense to enable it in all
utilities such as ls(1) that have little benefit to having it enabled.
Reported by: kib
This is currently an opt-in build flag. Once ASLR support is ready and stable
it should changed to opt-out and be enabled by default along with ASLR.
Each application Makefile uses opt-out to ensure that ASLR will be enabled by
default in new directories when the system is compiled with PIE/ASLR. [2]
Mark known build failures as NO_PIE for now.
The only known runtime failure was rtld.
[1] http://www.bsdcan.org/2014/schedule/events/452.en.html
Submitted by: Shawn Webb <lattera@gmail.com>
Discussed between: des@ and Shawn Webb [2]
options, so move their processing there. This fixes issues with
Makefiles that define NO_MAN=t and only inlcude bsd.*.mk files. A few
ports fell into this category, and they should be fixed by this change.
Also, for now, disable the warning about NO_foo being deprecated. More
work is needed than anticipated before we can do that, so kill the
noise for now.
/etc/src.conf to this file as well. Now, it will only affect builds of
/usr/src and not others that use the bsd.*.mk files. Specifically
don't install src.opts.mk so we can catch when it 'leaks' into
bsd.*.mk again and have there be errors when this happens. Future
commits will move to including src.opts.mk instead of bsd.own.mk when
all that's needed is one of the MK_FOO options from src.opts.mk.
Future options should be placed here, unless they directly affect a
bsd.*.mk file, in which case they should be placed in bsd.opts.mk.
we're preventing now with this policy. However, these edge cases
should be rare and all that set MK_FOO directly.
WITH_FOO and WITHOUT_FOO both being defined now result in the
non-default behavior happening silently. Users needing determinism
here fall into the edge case exception for MK_FOO setting.
code from the rest. Include bsd.opts.mk in bsd.own.mk to preserve
current behavior. Future revisions will replace the inclusion of
bsd.own.mk elsewhere with bsd.opts.mk or a more appropriate new
file that's still being finalized.