Add a build knob for _FORTIFY_SOURCE

In the future, we will Default to _FORTIFY_SOURCE=2 if SSP is enabled,
otherwise default to _FORTIFY_SOURCE=0. For now we default it to 0
unconditionally to ease bisect across older versions without the new
symbols, and we'll put out a call for testing.

include/*.h include their ssp/*.h equivalents as needed based on the
knob. Programs and users are allowed to override FORTIFY_SOURCE in their
Makefiles or src.conf/make.conf to force it off.

Reviewed by: des, markj
Relnotes: yes
Sponsored by: Stormshield
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D32308

rtld: use generated map file to check for some leaks from libc into rtld

Reviewed by: brooks, emaste (previous version)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D44136

rtld: unconditionally generate map file during build

It is needed at least to ensure that undesirable code is not linked into
rtld from libsys/libc, and adding the map file option each time is not
productive.

Reviewed by: brooks, emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D44136

Stop #defining FREEBSD_ELF

This was originally used (along with FREEBSD_AOUT) to prefer the use
of ELF in various tools instead of a.out as part of the a.out to ELF
transition in the 3.x days. The last use of it was removed from
<link.h> in commit 66422f5b7a1a6055f0b2358268eb902aab6e2e3e back in
2002, but various files still #define it.

Reviewed by: kevans, imp, emaste
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D42964

Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

libexec: Automatically generate rtld-elf list and generalise TAGS

Note that the pattern for matching is made slightly more specific, so as
to permit libcompats where one is a prefix of another (e.g. CheriBSD has
lib64 and lib64c).

Reviewed by: brooks, jhb, emaste, imp, kib
Differential Revision: https://reviews.freebsd.org/D41183

rtld: don't add extraneous -L directory when MK_TOOLCHAIN == no

rtld's Makefile used to add -L${LIBDIR} to LDFLAGS when MK_TOOLCHAIN was
no. This was done as part of a change to fix building rtld with
MK_TOOLCHAIN == no (although I'm not sure this part was necessary).

In any case as of 5f2e84015da7 libc_pic.a is built independent of the
MK_TOOLCHAIN setting and the main part of the workaround has already
been removed. Remove the rest now.

This reverts commit c0f5aeb0329d71e6b02379133c0c9c0145c9afea.

Reviewed by: jrtc27
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39938

rtld: Do not install libmap.conf when installing the COMPAT32 version

This has the effect of installing the same file twice at the same location
and confuse pkgbase as we add this file twice in the package config part.

MFC after: 1 week
Sponsored by: Beckhoff Automation GmbH & Co. KG

Add build system support for ASAN+UBSAN instrumentation

This adds two new options WITH_ASAN/WITH_UBSAN that can be set to
enable instrumentation of all binaries with AddressSanitizer and/or
UndefinedBehaviourSanitizer. This current patch is almost sufficient
to get a complete buildworld with sanitizer instrumentation but in
order to actually build and boot a system it depends on a few more
follow-up commits.

Reviewed By: brooks, kib, markj
Differential Revision: https://reviews.freebsd.org/D31043

rtld-elf: link libcompiler_rt on all architectures

Statically link rtld-elf with libcompiler_rt on all architectures so
that we don't need to try to pick and choose the bits we need from it
for each architecture (we now leave that to the linker). Compilers may
emit calls to support functions in this library, but because of the use
of the linker flag -nostdlib for rtld's special needs, the library is
not linked as normal.

Previously we had two different solutions. On some architectures, we
were able to extract reimplementations of the necessary builtin
functions from our special build of libc. On ARM, we just linked
libcompiler_rt.

This is motivated by the same issue as D26199 and D27665, but should be
a simpler solution that will apply to all architectures.

Reviewed by: arichardson, kib
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D27736

Do a sweep and remove most WARNS=6 settings

Repeating the default WARNS here makes it slightly more difficult to
experiment with default WARNS changes, e.g. if we did something absolutely
bananas and introduced a WARNS=7 and wanted to try lifting the default to
that.

Drop most of them; there is one in the blake2 kernel module, but I suspect
it should be dropped -- the default WARNS in the rest of the build doesn't
currently apply to kernel modules, and I haven't put too much thought into
whether it makes sense to make it so.

[PowerPC64LE] Use a shared LIBC_ARCH for powerpc64le.

Given that we have converted to ELFv2 for BE already, endianness is the only
difference between the two ARCHs.

As such, there is no need to differentiate LIBC_ARCH between the two.

Combining them like this lets us avoid needing to have two copies of several
bits for no good reason.

Sponsored by: Tag1 Consulting, Inc.

Don't explicitly specify c99 or gnu99 as the default is now gnu99.

MFC after: 2 weeks

Include FreeBSD ABI tag note in the ELF runtime loader.

Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D25306

Remove tests for obsolete compilers in the build system

Assume gcc is at least 6.4, the oldest xtoolchain in the ports tree.
Assume clang is at least 6, which was in 11.2-RELEASE. Drop conditions
for older compilers.

Reviewed by: imp (earlier version), emaste, jhb
MFC after: 2 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D24802

Move ARM specific flags to arm/Makefile.inc

Requested by: kib
MFC with: r360463

Don't allow to use FPU inside of rtld library.
Clang10 may use FPU instructions for optimizing operations with
memory blocks. But we don't want to do lengthy save/restore of all
FPU registers across each rtld_start() call.

MFC after: 3 week

rtld: clean up Makefile.

Move all MD statements into $MACHINE_ARCH/Makefile.inc.
Unconditionally apply version script to rtld, the interpreter is not
functional without it for long time.

Reviewed by: brooks, emaste
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D23083

libcompat: Correct rtld MLINKS

Don't install duplicate ld-elf.so.1.1 and ld.so.1 links in rtld-elf32.
Do install lib-elf32.so.1.1 and ldd32.1 links.

Reported by: madpilot

libcompat: build 32-bit rtld and ldd as part of "everything"

Alter bsd.compat.mk to set MACHINE and MACHINE_ARCH when included
directly so MD paths in Makefiles work. In the process centralize
setting them in LIBCOMPATWMAKEENV.

Alter .PATH and CFLAGS settings in work when the Makefile is included.

While here only support LIB32 on supported platforms rather than always
enabling it and requiring users of MK_LIB32 to filter based
TARGET/MACHINE_ARCH.

The net effect of this change is to make Makefile.libcompat only build
compatability libraries.

Changes relative to r354449:

Correct detection of the compiler type when bsd.compat.mk is used
outside Makefile.libcompat. Previously it always matched the clang
case.

Set LDFLAGS including the linker emulation for mips where -m32 seems to
be insufficent.

Reviewed by: imp, kib (origional version in r354449)
Obtained from: CheriBSD (conceptually)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22251

Revert r354449: libcompat: build 32-bit rtld and ldd as part of "everything"

Additional testing is required..

libcompat: build 32-bit rtld and ldd as part of "everything"

Alter bsd.compat.mk to set MACHINE and MACHINE_ARCH when included
directly so MD paths in Makefiles work. In the process centralize
setting them in LIBCOMPATWMAKEENV.

Alter .PATH and CFLAGS settings in work when the Makefile is included.

While here only support LIB32 on supported platforms rather than always
enabling it and requiring users of MK_LIB32 to filter based
TARGET/MACHINE_ARCH.

The net effect of this change is to make Makefile.libcompat only build
compatability libraries.

Reviewed by: imp, kib
Obtained from: CheriBSD (conceptually)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D22251

Reduce size of rtld by 22% by pulling in less code from libc

Currently RTLD is linked against libc_nossp_pic which means that any libc
symbol used in rtld can pull in a lot of depedencies. This was causing
symbol such as __libc_interposing and all the pthread stubs to be included
in RTLD even though they are not required. It turns out most of these
dependencies can easily be avoided by providing overrides inside of rtld.

This change is motivated by CHERI, where we have an experimental ABI that
requires additional relocation processing to allow the use of function
pointers inside of rtld. Instead of adding this self-relocation code to
RTLD I attempted to remove most function pointers from RTLD and discovered
that most of them came from the libc dependencies instead of being actually
used inside rtld.

A nice side-effect of this change is that rtld is now 22% smaller on amd64.

text data bss dec hex filename
0x21eb6 0xce0 0xe60 145910 239f6 /home/alr48/ld-elf-x86.before.so.1
0x1a6ed 0x728 0xdd8 113645 1bbed /home/alr48/ld-elf-x86.after.so.1

The number of R_X86_64_RELATIVE relocations that need to be processed on
startup has also gone down from 368 to 187 (almost 50% less).

Reviewed By: kib
Differential Revision: https://reviews.freebsd.org/D20663

ld-elf.so: make LD_DEBUG always functional.

This causes some increase of the dynamic linker size, but benefits of
avoiding compiling private copy or the linker when debugging is
required. definitely worth it.

The dbg() calls can be compiled out by defining LD_NO_DEBUG symbol.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

revert r341429 "disable BIND_NOW in libc, libthr, and rtld"

r345620 by kib@ fixed the rtld issue that caused a crash at startup
during resolution of libc's ifuncs with BIND_NOW.

PR: 233333
Sponsored by: The FreeBSD Foundation

Add WITH_PIE knob to build Position Independent Executables

Building binaries as PIE allows the executable itself to be loaded at a
random address when ASLR is enabled (not just its shared libraries).

With this change PIE objects have a .pieo extension and INTERNALLIB
libraries libXXX_pie.a.

MK_PIE is disabled for some kerberos5 tools, Clang, and Subversion, as
they explicitly reference .a libraries in their Makefiles. These can
be addressed on an individual basis later. MK_PIE is also disabled for
rtld-elf because it is already position-independent using bespoke
Makefile rules.

Currently only dynamically linked binaries will be built as PIE.

Discussed with: dim
Reviewed by: kib
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18423

Rename rtld-elf/malloc.c to rtld-elf/rtld_malloc.c.

Then malloc.c file name is too generic to use it for libthr.a.

Sponsored by: The FreeBSD Foundation
MFC after: 13 days

disable BIND_NOW in libc, libthr, and rtld

An issue remains with BIND_NOW and processes using threads. For now,
restore libc's BIND_NOW disable, and also disable BIND_NOW in rtld and
libthr.

A patch is in review (D18400) that likely fixes this issue, but just
disable BIND_NOW pending further testing after it is committed.

PR: 233333
Sponsored by: The FreeBSD Foundation

Revert r340843 - addressed independently in r340842!

rtld: Silence a false positive GCC 6.4.0 warning

The function reloc_non_plt has complicated variable lifetimes that GCC 6.4.0
(the version currently used by amd64-xtoolchain-gcc) misunderstands and
produces an erroneous warning about. Silence it to allow the -Werror build
to proceed.

Reviewed by: emaste

rtld-elf: fix more warnings to allow compiling with WARNS=6

Reviewed By: kib
Approved By: brooks (mentor)
Differential Revision: https://reviews.freebsd.org/D17154

rtld-elf: compile with WANRS=4 warnings other than -Wcast-align

Reviewed By: kib
Approved By: brooks (mentor)
Differential Revision: https://reviews.freebsd.org/D17153

Move libmap.conf to libexec/rtld-elf/

This leverages CONFS to handle the config file install.

Approved by: re (gjb), will (mentor)
Differential Revision: https://reviews.freebsd.org/D17161

Make rtld use libc_nossp_pic.a. Remove SSP shims.

Submitted by: Luis Pires
Reviewed by: brooks
Differential revision: https://reviews.freebsd.org/D15341

Compile reloc.o with -fno-jump-tables on MIPS.

In particular, the switch statement on the type of dynamic entries
in _rtld_relocate_nonplt_self() needs to not use a jump table since
jump tables on MIPS use local GOT entries which aren't initialized
until after this loop.

Suggested by: arichardson
Reviewed by: emaste
Sponsored by: DARPA / AFRL

Explicitly disable MK_COVERAGE

This doesn't work with --coverage enabled. It still doesn't link, but this
reduces the linker errors from 50~100 to 1.

Add HAS_TESTS to all Makefiles that are currently using the
`SUBDIR.${MK_TESTS}+= tests` idiom.

This is a follow up to r321912.

Convert traditional ${MK_TESTS} conditional idiom for including test
directories to SUBDIR.${MK_TESTS} idiom

This is being done to pave the way for future work (and homogenity) in
^/projects/make-check-sandbox .

No functional change intended.

MFC after: 1 weeks

Convert absolute links to relative links.
Style.Makefile(9) has been ignored to produce minimal diffs.

Approved by: grehan (mentor)
MFC after: 1 week

Assert that there is no unresolved symbols during rtld linking.

Reviewed by: emaste, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
X-Differential revision: https://reviews.freebsd.org/D8448

Update hint to utilize user variable.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

Fix race for incrementally rebuilding VERSION_MAP.

The dependency is needed in PROG_FULL since only the build of PROG_FULL
is using the LDFLAGS and depending on VERSION_MAP. This was not a problem
with MK_DEBUG_FILES==no since it only builds PROG.

This should probably be using bsd.lib.mk instead [1]

Reported by: swills, gjb
Reviewed by: emaste
Noted by: rgrimes [1]
Sponsored by: EMC / Isilon Storage Division
Approved by: re (kib)

WITHOUT_TOOLCHAIN: Fix build of rtld.

MK_TOOLCHAIN==no disables building and installing of pic archives.
c_pic.a is still needed for rtld though so force it to build in lib/libc
and link directly to the objdir version of it for rtld.

Somehow this has been broken since r148725.

Sponsored by: EMC / Isilon Storage Division

Remove libc, librtld_db, libthr packages, and further increase
the constraints on what needs to be installed in a specific to
maintain consistency during upgrades.

Create a new clibs package containing libraries that are needed
as a bare minimum for consistency.

With much help and input from: kib
Sponsored by: The FreeBSD Foundation

Include ld-elf.so and ld-elf32.so in the librtld_db
package.

Sponsored by: The FreeBSD Foundation

Follow-on to r291666: use -ffreestanding instead of -fno-builtin.

Requested by: kib

Fix build on GCC 5.2 where, at least on PPC64, the compiler would "optimize"
the malloc() + memset() in the local implementation of calloc() into a call
to calloc(), helpfully turning it into an infinite loop. Clean up some
unneeded flags on PPC64 while here.

MFC after: 1 month

Fix build after r291620.

"don't know how to make /Versions.def. Stop"

This was trying to define a target in bsd.symver.mk based on LIBCDIR which was
not yet defined. Switching the order of inclusion of bsd.prog.mk and
bsd.symver.mk fixes it and seems fine.

Pointyhat to: bdrewery
Sponsored by: EMC / Isilon Storage Division

Don't override LIB*DIR variables from src.libnames.mk.

In some cases switch to the LIB*SRCDIR value.

These recently were defined in r291327 and r291619.

Sponsored by: EMC / Isilon Storage Division

Use LIBEXECDIR for /usr/libexec.

MFC after: 1 week
Sponsored by: EMC / Isilon Storage Division

META_MODE: No need to fix the link in this case.

The exists(${DESTDIR}...) check runs with DESTDIR being blank. When the
target runs it does have DESTDIR=${STAGE_OBJTOP} via bsd.sys.mk. This
results in the first execution warning that the symlink is missing. The
second run does run fine. However, this chflags is not needed at all
for META_MODE/STAGING since we never had this path being a schg file
while using META_MODE.

Sponsored by: EMC / Isilon Storage Division

Change compiler setting to make default visibility of the symbols for
rtld on x86 to be hidden. This is a micro-optimization, which allows
intrinsic references inside rtld to be handled without indirection
through PLT. The visibility of rtld symbols for other objects in the
symbol namespace is controlled by a version script.

Reviewed by: kan, jilles
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks

Convert to LIBADD
Reduce overlinking

Remove MK_ARM_EABI, the armeb issues have been fixed. The code to support
the oabi is still in the tree, but it is expected this will be removed
as developers work on surrounding code.

With this commit the ARM EABI is the only supported supported ABI by
FreeBSD on ARMa 32-bit processors.

X-MFC after: never
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D876

Document the whole settings needed to build a debug version of rtld.

Sponsored by: The FreeBSD Foundation
MFC after: 3 days

Revert r267233 for now. PIE support needs to be reworked.

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

Test RTLD's new LD_LIBRARY_PATH_FDS variable.

Test LD_LIBRARY_PATH_FDS by linking a binary that requires a shared
library that isn't in any of the usual search paths. Ensure this fails
when we don't supply LD_LIBRARY_PATH_FDS or we pass invalid information
in it. Ensure it works when we pass the correct directory in various
places in the variable.

Approved by: rwatson (mentor)
MFC after: 3 weeks
Sponsored by: DARPA/AFRL

In preparation for ASLR [1] support add WITH_PIE to support building with -fPIE.

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 src.opts.mk in preference to bsd.own.mk except where we need stuff
from the latter.

Replace LIBGCC by LIBCOMPILER_RT.

We now use libcompiler_rt on all platforms now. Instead of referring
directly to -lgcc and LIBGCC, use -lcompiler_rt and LIBCOMPILER_RT.

When building for ARM EABI link against libgcc for the __aeabi_* functions.

Use absolute path for /usr/libexec/ld-elf.so.1 symlink.

Requested by: kan, kib

Use -h flags for chflags, so we won't remove 'schg' flag from system's
/libexec/ld-elf.so.1.

MFC after: 2 weeks

Do not change entire BINDIR, it might be needed later, just change
symlink target.

MFC after: 2 weeks

Change /usr/libexec/ld-elf.so.1 to point at ../../libexec/ld-elf.so.1
instead of /libexec/ld-elf.so.1. Below in the Makefile we execute
'chflags noschg ${DESTDIR}/usr/libexec/ld-elf.so.1', which follows
symlink and removes 'schg' flag from system's /libexec/ld-elf.so.1
instead of the one in DESTDIR. It is also more friendly to use
replative paths in symlink in case of jail/chroot environments.

Obtained from: WHEEL Systems
MFC after: 2 weeks

Remove libssp_nonshared from the rtld linking set. The only use for the
library was definition for the weak alias of __stack_chk_fail.

No objections from: kan
MFC after: 2 weeks

Centralize the calculation of the top source directory. This
simplifies the build of rtld with partial checkout, allowing to
override only one place to reference other tree.

Submitted by: bde
MFC after: 2 weeks

Add support for preinit, init and fini arrays. Some ABIs, in
particular on ARM, do require working init arrays.

Traditional FreeBSD crt1 calls _init and _fini of the binary, instead
of allowing runtime linker to arrange the calls. This was probably
done to have the same crt code serve both statically and dynamically
linked binaries. Since ABI mandates that first is called preinit
array functions, then init, and then init array functions, the init
have to be called from rtld now.

To provide binary compatibility to old FreeBSD crt1, which calls _init
itself, rtld only calls intializers and finalizers for main binary if
binary has a note indicating that new crt was used for linking. Add
parsing of ELF notes to rtld, and cache p_osrel value since we parsed
it anyway.

The patch is inspired by init_array support for DragonflyBSD, written
by John Marino.

Reviewed by: kan
Tested by: andrew (arm, previous version), flo (sparc64, previous version)
MFC after: 3 weeks

Rtld links with the specially built pic static libc library to get some
C runtime services, like printf(). Unfortunately, the multithread-safeness
measures in the libc do not work in rtld environment.

Rip the kernel printf() implementation and use it in the rtld instead of
libc version. This printf does not require any shared global data and thus
is mt-safe. Systematically use rtld_printf() and related functions, remove
the calls to err(3).

Note that stdio is still pulled from libc due to libmap implementaion using
fopen(). This is safe but unoptimal, and can be changed later.

Reported and tested by: pgj
Diagnosed and reviewed by: kan (previous version)
Approved by: re (bz)

Compile RTLD with global dot symbols on 64-bit PowerPC, as a crutch for
GDB's ability to locate r_debug_state (which is actually the only function
that need be compiled this way).

Add a hook to pass debug flags to the build of rtld when doing make in
the rtld directory.

Reviewed by: kan

Use -fPIC to build libexec/rtld-elf on sparc64, so it will also be able
to link with newer binutils, without overflowing the GOT.

Obtained from: projects/binutils-2.17

Use -fPIC for rtld-elf, so it can link on sparc64.

Unbreak ia64.

With r169630 I disabled symbol versioning because it broke rtld. With
r211706 rtld got broken for ia64 & powerpc64. It was fixed for powerpc64
with r212497. In between, r211749 removed the exports table because the
version script handled the exports. But wait, symbol versioning was
disabled on ia64.

With exports controlled by the version script and symbol versioning
disabled, all symbols are exported and too many symbols bind to the
definition in rtld. Let's just say that waird things happen.

So, enable symbol versioning on ia64 and apply a work-around for the
SIGSEGV that triggered r169630 to begin with: when rtld relocates
itself, it comes across r_debug_state and for some reason can't find the
definition. This causes a failure, relocation aborts and null pointers
galore. The work-around is to ignore the missing definition when rtld
is relocating itself and keep going.

Maybe with the next binutils this will all go away. Maybe not, in
which case I still need to figure out why r_debug_state cannot be found.

BTW: r_debug_state is in the symbol map -- I don't think any other rtld
symbols that rtld references are in the symbol map...

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Make RTLD work on powerpc64 again. If there is a sub-directory named
MACHINE_ARCH, use that specific one, otherwise use MACHINE_CPUARCH.

Reviewed by: imp

MFtbemd:

Prefer MACHNE_CPUARCH to MACHINE_ARCH in most contexts where you want
to test of all the CPUs of a given family conform.

RTLD support for powerpc64. A few small modifications to the Makefile
and symbol map are required to support various consequences of the dot
symbol scheme:

- Symbols beginning with a dot are reserved, so start private symbols with
an underscore.
- In order to set RTLD breakpoints, gdb must be able to locate the text
entry point, not the data section function descriptor, so add
.r_debug_state to the symbol map on powerpc64.

Obtained from: projects/ppc64

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

Make WARNS=6 the default for libexec/.

Just like bin/ and sbin/, I think setting WARNS to the highest value
possible will make it more attractive for people to fix warnings.

- The WARNS variable is set in the Makefile in the directory of the
application itself, making it more likely that it will be removed out
of curiosity to see what happens.
- New applications will most likely build with WARNS=6 out of the box,
because the author would more likely fix the warnings during
development than lower WARNS.

Unfortunately almost all apps in libexec require a lowered value of
WARNS.

Second attempt at eliminating .text relocations in shared libraries
compiled with stack protector.

Use libssp_nonshared library to pull __stack_chk_fail_local symbol into
each library that needs it instead of pulling it from libc. GCC
generates local calls to this function which result in absolute
relocations put into position-independent code segment, making dynamic
loader do extra work every time given shared library is being relocated
and making affected text pages non-shareable.

Reviewed by: kib
Approved by: re (kib)

Back out previous revision until better tested fix is ready.

Approved by: re (impliciti, by approving previos check-in)

Eliminate .text relocations in shared libraries compiled with stack protector.

Use libssp_nonshared library to pull __stack_chk_fail_local symbol into
each library that needs it instead of pulling it from libc. GCC generates
local calls to this function which result in absolute relocations put into
position-independent code segment, making dynamic loader do extra work everys
time given shared library is being relocated and making affected text pages
non-shareable.

Reviewed by: kib
Approved by: re (kensmith)

Fix build when WITH_SSP is set explicitly.

Submitted by: Jeremie Le Hen

- Import the HEAD csup code which is the basis for the cvsmode work.

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>

Don't enable symbol versioning on ia64 for now. It causes
symbol lookup failures that later result in null-pointer
dereferences. This needs looking into, but since we're
close to release it's possible that it's not resolved before
that time.

Enable symbol versioning by default. Use WITHOUT_SYMVER to disable it.
Warning, after symbol versioning is enabled, going back is not easy
(use WITHOUT_SYMVER at your own risk).

Change the default thread library to libthr.

There most likely still needs to be a version bump for at least the
thread libraries. If necessary, this will happen later.

Retire rtld-specific Versions.def. Symbols exported by rtld are supposed
to override weak symbols exported by libc, so by definition these two
are using the same symbol version names.

Reflect the reality by referring to libc's Versions.def directly.

Bring rtld exports in line with corresponding symbols exported from
libc.

Disable SYMVER_DEFAULT n rtld until its implications are understood
better.

Prepare rtld for symbol versioning. Disable it by default for now.

So do it like we do in usr.bin/tip/tip/Makefile. ;)

Revert previous commit. As ru explains:

In the old world (as the surrounding comment in makefile says), there
was the /usr/libexec/ld-elf.so.1 binary which is now a symlink to
/libexec/ld-elf.so.1. To symlink, we need to make sure that the
_target_ (and the target is /usr/libexec/ld-elf.so.1) doesn't have
"schg" flag set. A real solution is to protect the chflags call only if
target exists, like we do in usr.bin/tip/tip/Makefile.

Requested by: ru

Avoid an (ignored) error by invoking chflags on the link target, not the
symlink.

PR: kern/73016
Submitted by: John E. Hein <jhein@timing.com>
MFC after: 1 week

Introduce the PRECIOUSPROG knob in bsd.prog.mk, similar
to PRECIOUSLIB from bsd.lib.mk. The side effect of this
is making installing the world under jail(8) possible by
using another knob, NOFSCHG.

Reviewed by: oliver

For variables that are only checked with defined(), don't provide
any fake value.

This comment should have been removed in the previous commit.

Spotted out by: marcus, simon

Woohoo !
the latest binutils import mades this gross hack useless, so just remove it.

Work around a problem somewhere with binutils (?) on arm, hopefully without
breaking any other arch this time.

Fix breakage caused by alphabetically sorting SRCS: rtld_start.S must come first!
The previous version made all shared binaries dump core.

Import arm bits for rtld-elf.

Obtained from: NetBSD

Add initial support for compiling a special 32 bit version of
ld-elf.so.1 on 64 bit systems. Most of this involves using alternate
paths, environment variables and diagnostic messages.

The build glue is seperate.

Retire the WITH_LIBMAP compile knob; libmap is now a standard feature.

Forgot one instance of ld-elf.so.1. Convert to ${PROG}

Pointed out by: obrien

Don't forget to honor DESTDIR. Also switch over to using PROG instead of
the binary name directly.

Don't forget to chflags noschg the existing binary so we can symlink
over it safely.

Pointed out by: yosimoto@waishi.jp

As long threatened, stage 2 of making a dynamically-linked root a reality.
Install rtld into /libexec.

Set CSTD to gnu99. We can only use on of the gnu?9 C languages.
We can't use c89 due to use of 'inline', and c99 produces bad code.

Allow threading libraries to register their own locking
implementation in case default one provided by rtld is
not suitable.

Consolidate various identical MD lock implementation into
a single file using appropriate machine/atomic.h.

Approved by: re (scottl)

Dynamic object dependency mapping: libmap.

This is an optional feature, disabled by default.

This will be useful to people testing the various POSIX threading
libraries under -CURRENT but can easily serve other needs.

Advertize rtld(1) as ld.so(1) in manual pages world

Dillon's recent commits to the dynamic linker without running them
by me first have given me a good excuse to drop my MAINTAINERship.

MFC after: 1 week

Use new backup feature of install(1).

- Backout botched attempt to intoduce MANSECT feature.
- MAN[1-9] -> MAN.

We shouldn't use cp to save the old ld-elf.so.1. Use the sanctioned tool
${INSTALL} with -C -p instead.

When installing the dynamic linker, save the previous version in
"ld-elf.so.1.old". The dynamic linker is a critical component of
the system, and it is difficult to recover if it is damaged and
there isn't a working backup available. For instance, parts of
the toolchain such as the assembler are dynamically linked, making
it impossible to build a new dynamic linker if the installed one
doesn't work.

Fixed missing DPADDs.

Fixed some style bugs (some usual ones for LDADD, and misformatting of
$FreeBSD$).

Add a manual page for the ELF dynamic linker. I initially created
rtld.1 by means of a repository copy from "src/libexec/rtld-aout/rtld.1".
Then I edited it to make it (more) accurate for the ELF dynamic
linker.

Add a new function dllockinit() for registering thread locking
functions to be used by the dynamic linker. This can be called by
threads packages at start-up time. I will add the call to libc_r
soon.

Also add a default locking method that is used up until dllockinit()
is called. The default method works by blocking SIGVTALRM, SIGPROF,
and SIGALRM in critical sections. It is based on the observation
that most user-space threads packages implement thread preemption
with one of these signals (usually SIGVTALRM).

The dynamic linker has never been reentrant, but it became less
reentrant in revision 1.34 of "src/libexec/rtld-elf/rtld.c".
Starting with that revision, multiple threads each doing lazy
binding could interfere with each other. The usual symptom was
that a symbol was falsely reported as undefined at start-up time.
It was rare but not unseen. This commit fixes it.

$Id$ -> $FreeBSD$

Add a MAINTAINER line naming myself. We control the vertical. We
control the horizontal.

Eliminate all machine-dependent code from the main source body and
the Makefile, and move it down into the architecture-specific
subdirectories.

Eliminate an asm() statement for the i386.

Make the dynamic linker work if it is built as an executable instead
of as a shared library. See i386/Makefile.inc to find out how to
do it. Note, this change is not enabled and it might never be
enabled. But it might be useful in the future. Building the
dynamic linker as an executable should make it start up faster,
because it won't have any relocations. But in practice I suspect
the difference is negligible.

- Set the system immutable flag when installing ld.so to avoid people
accidentally clobbering it.

Submitted by: numberous people on -current

Add alpha support.

Submitted by: John Birrell <jb@cimlogic.com.au> (with extra hacks by me)
Obtained from: Probably NetBSD

Add "-C" to INSTALLFLAGS to install atomically. An elf->elf
installworld dies at this point otherwise, leaving the system
without a dynamic linker.

Add GDB support. The method and some of the code came from NetBSD's elf
runtime linker.

Import the ELF dynamic linker. This is the ElfKit version with
quite a few enhancements and bug fixes. There are still some known
deficiencies, but it should be adequate to get us started with ELF.

Submitted by: John Polstra <jdp@polstra.com>