This is a mostly-unmodified copy of the various *_chk implementations
and headers from NetBSD, without yet modifying system headers to start
actually including them. A future commit will also apply the needed
bits to fix ssp/unistd.h.
Reviewed by: imp, pauamma_gundo.com (both previous versions), kib
Sponsored by: Stormshield
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D32306
For libssp.so, rebuild stack_protector.c with FORTIFY_SOURCE stubs that just
abort built into it.
For libssp_nonshared.a, steal stack_protector_compat.c from
^/lib/libc/secure and massage it to maintain that __stack_chk_fail_local
is a hidden symbol.
libssp is now built unconditionally regardless of {WITH,WITHOUT}_SSP in the
build environment, and the gcclibs version has been disconnected from the
build in favor of this one.
PR: 242950 (exp-run)
Reviewed by: kib, emaste, pfg, Oliver Pinter (earlier version)
Also discussed with: kan
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22943
