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]
Use WARNS?= instead of WARNS=
For this to work properly for all part is the subdirectories
the WARNS assignments in Makefile.inc0 are moved to the correspondning
Makefile.inc.
Approved by: obrien (binutils maintainer)
Tested by: make universe
libraries in LDADD so that `make checkdpadd' doesn't report non-errors.
Fixed some style bugs (the usual ones for DPADD and LDADD, and misformatting
of $FreeBSD$).
be worth much effort. Install all i386 binutils programs in
"/usr/libexec/elf". Disable a.out support in libbfd. It's too
dangerous to leave it in. Some of the utilities think they can
handle a.out, but they generate bad object files.
This finishes up the binutils import. But I am leaving it disabled
in "src/gnu/usr.bin/Makefile" for now. It is not used by anything
yet, so I'll take this opportunity to run one more round of tests
before enabling it.