libexec: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

R

libexec: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

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rtld/arm: fix initial-exec (IE) thread-local storage relocation

net/frr[89] revealed an interesting edge-case on arm when dynamically
linking a shared library that declares more than one static TLS

rtld/arm: fix initial-exec (IE) thread-local storage relocation

net/frr[89] revealed an interesting edge-case on arm when dynamically
linking a shared library that declares more than one static TLS variable
with at least one using the "initial-exec" TLS model. In the case
of frr[89], this library was libfrr.so which essentially does the
following:

#include <stdio.h>

#include "lib.h"

static __thread int *a
__attribute__((tls_model("initial-exec")));

void lib_test()
{
static __thread int b = -1;

printf("&a = %p\n", &a);
printf(" a = %p\n", a);

printf("\n");

printf("&b = %p\n", &b);
printf(" b = %d\n", b);
}

Allocates a file scoped `static __thread` pointer with
tls_model("initial-exec") and later a block scoped TLS int. Notice in
the above minimal reproducer, `b == -1`. The relocation process does
the wrong thing and ends up pointing both `a` and `b` at the same place
in memory.

The output of the above in the broken state is:

&a = 0x4009c018
a = 0xffffffff

&b = 0x4009c018
b = -1

With the patch applied, the output becomes:

&a = 0x4009c01c
a = 0x0

&b = 0x4009c018
b = -1

Reviewed by: kib
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D42415/

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rtld: introduce STATIC_TLS_EXTRA

The new STATIC_TLS_EXTRA variable provides a means for applications
to increases the size of the extra static TLS space allocated by
rtld beyond the default of '128'

rtld: introduce STATIC_TLS_EXTRA

The new STATIC_TLS_EXTRA variable provides a means for applications
to increases the size of the extra static TLS space allocated by
rtld beyond the default of '128'. This extra static TLS space is used
for objects loaded with dlopen.

The value specified in the variable must be no less than the default
value and no greater than the maximum allowed value for size_t type.

If an invalid value is specified, rtld will ignore it and just use
the default value.

The rtld(1) man page is updated to document this new option.

Obtained from: Juniper Networks, Inc.
Differential Revision: https://reviews.freebsd.org/D42025

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Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

rtld-elf: Remove set but unused variable on 32-bit arm.

rtld: rename tls_done to tls_static

The meaning of the flag is that static TLS allocation was done.

Taken from NetBSD Joerg Sonnenberger change for src/libexec/ld.elf_so/tls.c
rev. 1.18.

Sponsored

rtld: rename tls_done to tls_static

The meaning of the flag is that static TLS allocation was done.

Taken from NetBSD Joerg Sonnenberger change for src/libexec/ld.elf_so/tls.c
rev. 1.18.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

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rtld-elf: Remove libsoft support

Remove support for loading libsoft libraries.

Sponsored by: Netflix

TLS: Use <machine/tls.h> for libc and rtld.

- Include <machine/tls.h> in MD rtld_machdep.h headers.

- Remove local definitions of TLS_* constants from rtld_machdep.h
headers and libc using the va

TLS: Use <machine/tls.h> for libc and rtld.

- Include <machine/tls.h> in MD rtld_machdep.h headers.

- Remove local definitions of TLS_* constants from rtld_machdep.h
headers and libc using the values from <machine/tls.h> instead.

- Use _tcb_set() instead of inlined versions in MD
allocate_initial_tls() routines in rtld. The one exception is amd64
whose _tcb_set() invokes the amd64_set_fsbase ifunc. rtld cannot
use ifuncs, so amd64 inlines the logic to optionally write to fsbase
directly.

- Use _tcb_set() instead of _set_tp() in libc.

- Use '&_tcb_get()->tcb_dtv' instead of _get_tp() in both rtld and libc.
This permits removing _get_tp.c from rtld.

- Use TLS_TCB_SIZE and TLS_TCB_ALIGN with allocate_tls() in MD
allocate_initial_tls() routines in rtld.

Reviewed by: kib, jrtc27 (earlier version)
Differential Revision: https://reviews.freebsd.org/D33353

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rtld-elf/paths.h: Make it usable outside rtld

but still for tightly coupled things like ldd(1)

Rename paths.h to rtld_paths.h.
Add guard for rtld-specific externs declarations.
Add _COMPAT32_BASENA

rtld-elf/paths.h: Make it usable outside rtld

but still for tightly coupled things like ldd(1)

Rename paths.h to rtld_paths.h.
Add guard for rtld-specific externs declarations.
Add _COMPAT32_BASENAME_RTLD and _COMPAT32_PATH_RTLD.

Reviewed by: arichardson, jhb
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32464

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Remove the last users of ARM_TP_ADDRESS

This was only needed on 32-bit arm prior to ARMv6. As we only support
ARMv6 or later remove it.

Reviewed by: mannu
Sponsored by: Innovate UK
Differential Rev

Remove the last users of ARM_TP_ADDRESS

This was only needed on 32-bit arm prior to ARMv6. As we only support
ARMv6 or later remove it.

Reviewed by: mannu
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D29624

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rtld-elf(1): remove obsolete pre_init() hook

It's no longer used since 600ee699ed2805894f5972c6ac2c3d17dca7f6ce
and r358358 respectively.

Handle non-plt IRELATIVE relocations, at least for x86.

lld 10.0 seems to generate this relocation for rdtsc_mb() ifunc in our libc.

Reported, reviewed, and tested by: dim (amd64, previous version)

Handle non-plt IRELATIVE relocations, at least for x86.

lld 10.0 seems to generate this relocation for rdtsc_mb() ifunc in our libc.

Reported, reviewed, and tested by: dim (amd64, previous version)
Discussed with: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D23652

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rtld: attempt to fix reloc_nonplt_object TLS allocation

allocate_tls_offset returns true on success. This still needs more
testing and review, but this change is consistent with other archs.

PR:

rtld: attempt to fix reloc_nonplt_object TLS allocation

allocate_tls_offset returns true on success. This still needs more
testing and review, but this change is consistent with other archs.

PR: 236880
Reported by: Andrew Gierth <andrew@tao11.riddles.org.uk>
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation

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Improve R_AARCH64_TLSDESC relocation.
The original code did not support dynamically loaded libraries and used
suboptimal access to TLS variables.
New implementation removes lazy resolving of TLS relo

Improve R_AARCH64_TLSDESC relocation.
The original code did not support dynamically loaded libraries and used
suboptimal access to TLS variables.
New implementation removes lazy resolving of TLS relocation - due to flaw
in TLSDESC design is impossible to switch resolver function at runtime
without expensive locking.

Due to this, 3 specialized resolvers are implemented:
- load time resolver for TLS relocation from libraries loaded with main
executable (thus with known TLS offset).
- resolver for undefined thread weak symbols.
- slower lazy resolver for dynamically loaded libraries with fast path for
already resolved symbols.

PR: 228892, 232149, 233204, 232311
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D18417

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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

Fix wrong offset calculation for R_ARM_TLS_TPOFF32 relocations.
TLS_TCB_SIZE is already accounted in defobj-> tlsoffset so all these symbols
were incorrectly relocated by +8.

Note:
The only consumer

Fix wrong offset calculation for R_ARM_TLS_TPOFF32 relocations.
TLS_TCB_SIZE is already accounted in defobj-> tlsoffset so all these symbols
were incorrectly relocated by +8.

Note:
The only consumer (for all binaries on my ARM board) of R_ARM_TLS_TPOFF32
relocation is _ThreadRuneLocale variable. And the incorrectly relocated
ThreadRuneLocale accidentally pointed to zeroed memory before memory layout
change from D16510 had changed status quo.

MFC after: 3 weeks
Reviewed by: imp, jhb
Approved by: re (marius)

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o Let rtld(1) set up psABI user trap handlers prior to executing the
objects' init functions instead of doing the setup via a constructor
in libc as the init functions may already depend on these

o Let rtld(1) set up psABI user trap handlers prior to executing the
objects' init functions instead of doing the setup via a constructor
in libc as the init functions may already depend on these handlers
to be in place. This gets us rid of:
- the undefined order in which libc constructors as __guard_setup()
and jemalloc_constructor() are executed WRT __sparc_utrap_setup(),
- the requirement to link libc last so __sparc_utrap_setup() gets
called prior to constructors in other libraries (see r122883).
For static binaries, crt1.o still sets up the user trap handlers.
o Move misplaced prototypes for MD functions in to the MD prototype
section of rtld.h.
o Sprinkle nitems().

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End softfp->hardfp transition period for arm

On hard-float 32-bit arm platforms, always search for the soft float
binaries in the alternative locations.

Sponsored by: Netflix
Differential Review: h

End softfp->hardfp transition period for arm

On hard-float 32-bit arm platforms, always search for the soft float
binaries in the alternative locations.

Sponsored by: Netflix
Differential Review: https://reviews.freebsd.org/D12274
MFC After: 1 week

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Implement LD_BIND_NOT knob for rtld.

From the manpage:
When set to a nonempty string, prevents modifications of the PLT slots
when doing bindings. As result, each call of the PLT-resolved
function

Implement LD_BIND_NOT knob for rtld.

From the manpage:
When set to a nonempty string, prevents modifications of the PLT slots
when doing bindings. As result, each call of the PLT-resolved
function is resolved. In combination with debug output, this provides
complete account of all bind actions at runtime.

Same feature exists on Linux and Solaris.

Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks

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Adjust r308689 to make rtld compilable with either in-tree or
(hopefully) stock gcc 4.2.1 on i386 and other arches.

In particular:
- Do not use %ebx in the asm constraints on i386, since rtld is
c

Adjust r308689 to make rtld compilable with either in-tree or
(hopefully) stock gcc 4.2.1 on i386 and other arches.

In particular:
- Do not use %ebx in the asm constraints on i386, since rtld is
compiled with -fPIC and gcc cannot handle GOT-base register reload
(clang and newer gcc can).
- Avoid direct use of [static N] construct in the function
declaration/definion. In-tree gcc was patched to support this, but
stock 4.2.1 cannot handle the feature.

Requested by: bde
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

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Pass CPUID[1] %edx (cpu_feature), %ecx (cpu_feature2) and
CPUID[7].%ebx (cpu_stdext_feature), %ecx (cpu_stdext_feature2) to the
ifunc resolvers on x86.

It is much more clean to use CPUID instruction

Pass CPUID[1] %edx (cpu_feature), %ecx (cpu_feature2) and
CPUID[7].%ebx (cpu_stdext_feature), %ecx (cpu_stdext_feature2) to the
ifunc resolvers on x86.

It is much more clean to use CPUID instruction in usermode to retrieve
this information than to pass AT_HWCAP aux vector from kernel, on
x86. Still, the change does allow for use of AT_HWCAP on arches where it is
needed, by passing aux array to ifunc_init() initializer which should
prepare arguments for ifunc resolvers.

Current signature for resolvers on x86 is
func_t iresolve(uint32_t cpu_feature, uint32_t cpu_feature2,
uint32_t cpu_stdext_feature, uint32_t cpu_stdext_feature2);
where arguments have identical meaning as the kernel variables of the
same name. The ABIs allow to use resolvers with the void or shortened
list of arguments.

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

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rtld-elf: use NULL instead of zero for pointers.

Do not call callbacks for dl_iterate_phdr(3) with the rtld bind and
phdr locks locked. This allows to call rtld services from the
callback, which is only reasonable for dlopen(path, RTLD_NOLOAD) to

Do not call callbacks for dl_iterate_phdr(3) with the rtld bind and
phdr locks locked. This allows to call rtld services from the
callback, which is only reasonable for dlopen(path, RTLD_NOLOAD) to
test existence of the library in the image, and for dlsym(). The
later might still be not quite safe, due to the lazy resolution of
filters.

To allow dropping the locks around iteration in dl_iterate_phdr(3), we
insert markers to track current position between relocks. The global
objects list is converted to tailq and all iterators skip markers,
globallist_next() and globallist_curr() helpers are added.

Reported and tested by: davide
Reviewed by: kan
Sponsored by: The FreeBSD Foundation
MFC after: 3 weeks

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Restore ABI variants now that ldconfig groks -soft. In addition, as a
transition mechanism, if we don't have /usr/libsoft, assume that soft
float ABI binaries are the default, so treat them as defaul

Restore ABI variants now that ldconfig groks -soft. In addition, as a
transition mechanism, if we don't have /usr/libsoft, assume that soft
float ABI binaries are the default, so treat them as default binaries.
When we've fully transitioned, it will make no sense to do this stat,
and it will be removed.

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Create a generalized exec hook that different architectures can hook
into if they need to, but default to no action.

Differential Review: https://reviews.freebsd.org/D2718