rtld: Add arch_digest_dynamic

This will be used to handle the DT_AARCH64_VARIANT_PCS tag.

Reviewed by: kib
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45117

rtld: Add MD_OBJ_ENTRY to extend Struct_Obj_Entry

Add a macro the architectures can use to add per-arch fields to
Struct_Obj_Entry.

Reviewed by: kib
Sponsored by: Arm Ltd
Differential Revision: htt

rtld: Add MD_OBJ_ENTRY to extend Struct_Obj_Entry

Add a macro the architectures can use to add per-arch fields to
Struct_Obj_Entry.

Reviewed by: kib
Sponsored by: Arm Ltd
Differential Revision: https://reviews.freebsd.org/D45116

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Support BTI in rtld

Read the elf note to decide when to set the guard page on arm64.

Reviewed by: kib
Sponsored by: Arm Ltd
Sponsored by: The FreeBSD Foundation
Differential Revision: https://revie

Support BTI in rtld

Read the elf note to decide when to set the guard page on arm64.

Reviewed by: kib
Sponsored by: Arm Ltd
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39452

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Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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rtld: Revert "When loading dso without PT_GNU_STACK phdr, only call"

After the removal of ia64 and sparc64, all current architectures
support executable stacks at an architectural level.

This rever

rtld: Revert "When loading dso without PT_GNU_STACK phdr, only call"

After the removal of ia64 and sparc64, all current architectures
support executable stacks at an architectural level.

This reverts commit 1290d38ac50b3afa7e5781d9d97346a1042c736c.

Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D37904

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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: Remove calculate_tls_end

Variant I architectures use off and Variant II ones use size + off.
Define TLS_VARIANT_I/TLS_VARIANT_II symbols similarly to how libc
handles it.

Reviewed by: kib
MFC

rtld: Remove calculate_tls_end

Variant I architectures use off and Variant II ones use size + off.
Define TLS_VARIANT_I/TLS_VARIANT_II symbols similarly to how libc
handles it.

Reviewed by: kib
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31539
Differential revision: https://reviews.freebsd.org/D31541

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rtld: define TLS_DTV_OFFSET on all architectures

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29623

Align initial-exec TLS segments to the p_vaddr % align.

This is continuation of D21163/r359634, which handled the alignment
for global mode.

Non-x86 arches are not handled, maintainers are welcomed

Align initial-exec TLS segments to the p_vaddr % align.

This is continuation of D21163/r359634, which handled the alignment
for global mode.

Non-x86 arches are not handled, maintainers are welcomed.

Tested by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D24366

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libexec: adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone -

libexec: adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

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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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Merge ^/head r312207 through r312308.

MFhead@r312305

rtld: do not rely on a populated GOT on amd64

On rela architectures GNU BFD ld and gold store the relocation addend
in GOT entries (in addition to the relocation's r_addend field).
rtld previously r

rtld: do not rely on a populated GOT on amd64

On rela architectures GNU BFD ld and gold store the relocation addend
in GOT entries (in addition to the relocation's r_addend field).
rtld previously relied on this to access its own _DYNAMIC symbol in
order to apply its own relocations.

However, recording addends in the GOT is not specified by the ABI,
and some versions of LLVM's LLD linker leave the GOT uninitialized on
rela architectures.

BFD ld does not populate the GOT on sparc64, and sparc64 rtld has a
machine-dependent rtld_dynamic_addr() function that returns the
_DYNAMIC address. Use the same approach on amd64, obtaining the %rip-
relative _DYNAMIC address following a suggestion from Rafael Espíndola.

Architectures other than amd64 should be addressed in future work.

PR: 214972
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D9180

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Merge ^/head r308491 through r308841.

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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MFH @r294567

Merge ^/head r293036 through r293174.

MFH r289384-r293170

Sponsored by: The FreeBSD Foundation

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

Catch up with HEAD (r280229-r284686).

Merge sync of head

MFH: r280643-r281852

Sponsored by: The FreeBSD Foundation

Merge from HEAD