Enable GCC stack protection (aka Propolice) for userland:

- It is opt-out for now so as to give it maximum testing, but it may be
  turned opt-in for stable branches depending on the consensus.  You
  can turn it off with WITHOUT_SSP.
- WITHOUT_SSP was previously used to disable the build of GNU libssp.
  It is harmless to steal the knob as SSP symbols have been provided
  by libc for a long time, GNU libssp should not have been much used.
- SSP is disabled in a few corners such as system bootstrap programs
  (sys/boot), process bootstrap code (rtld, csu) and SSP symbols themselves.
- It should be safe to use -fstack-protector-all to build world, however
  libc will be automatically downgraded to -fstack-protector because it
  breaks rtld otherwise.
- This option is unavailable on ia64.

Enable GCC stack protection (aka Propolice) for kernel:
- It is opt-out for now so as to give it maximum testing.
- Do not compile your kernel with -fstack-protector-all, it won't work.

Submitted by:	Jeremie Le Hen <jeremie@le-hen.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/share/mk/bsd.sys.mk b/share/mk/bsd.sys.mk
index 96432c1..920fc25 100644
--- a/share/mk/bsd.sys.mk
+++ b/share/mk/bsd.sys.mk
@@ -74,5 +74,11 @@ CWARNFLAGS	+=	-Werror
 CWARNFLAGS	+=	-Wno-unknown-pragmas
 .endif
 
+.if ${MK_SSP} != "no" && ${CC} != "icc" && ${MACHINE_ARCH} != "ia64"
+# Don't use -Wstack-protector as it breaks world with -Werror.
+SSP_CFLAGS	?=	-fstack-protector
+CFLAGS		+=	${SSP_CFLAGS}
+.endif
+
 # Allow user-specified additional warning flags
 CFLAGS		+=	${CWARNFLAGS}