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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD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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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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[PowerPC] powerpc32 rtld IFUNC handling code

As PowerPC is moving to clang, we can finally start taking advantage of
IFUNC.

Implement the MD parts of IFUNC handling for rtld.

Currently, it is nece

[PowerPC] powerpc32 rtld IFUNC handling code

As PowerPC is moving to clang, we can finally start taking advantage of
IFUNC.

Implement the MD parts of IFUNC handling for rtld.

Currently, it is necessary to look for R_PPC_IRELATIVE in the PLT in
addition to RELA. This is an ABI violation, but LLD9 has some .iplt bugs
that require this as a workaround.

Reviewed by: jhibbits
Differential Revision: https://reviews.freebsd.org/D22855

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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

This commit reverts 338930. The approach was wrong.

Fix the issue with subtracting the TLS_TCB_SIZE too when we are trying to get
the 'where' in the R_PPC_TPREL32 case. At allocation time we added a

This commit reverts 338930. The approach was wrong.

Fix the issue with subtracting the TLS_TCB_SIZE too when we are trying to get
the 'where' in the R_PPC_TPREL32 case. At allocation time we added an offset
and the TLS_TCB_SIZE. This has to be subtracted as well.

Now all the issues reported are fixed. Tests were done on G4 and G5 PowerMac's.
Additionally I ran the tls tests from the gcc test suite and made sure the
results are as good as pre 338486.

Thanks to tuexen for reporting the malfunction and for patient testing.
Also testing thanks goes to jhibbits.

Reported by: tuexen
Discussed with: jhibbits, nwhitehorn
Approved by: re (gjb)
Pointyhat to: andreast

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Bring the 32-bit powerpc (PowerMac) back to live. The commit 338486 reworked
some TLS bits. This broke operation on the PowerMac. Namely one could not login.
At login the screen/shell was giving back

Bring the 32-bit powerpc (PowerMac) back to live. The commit 338486 reworked
some TLS bits. This broke operation on the PowerMac. Namely one could not login.
At login the screen/shell was giving back lots of backslashes and the login
shell dumped core.

The fix to this issue is to revert the powerpc commit from 338486 and to
increase the TLS_TCB_SIZE to 16.
Reverting only did not help, login was possible but userland applications
aborted with strange messages.

I tested this patch with world/kernel builds and with port upgrades.
Additionally a full gcc8 bootstrap was successfully completed.

Reviewed by: jhibbits@
Approved by: re (Glen)

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Rework rtld's TLS Variant I implementation to match r326794

The above commit fixed handling overaligned TLS segments in libc's
TLS Variant I implementation, but rtld provides its own implementation

Rework rtld's TLS Variant I implementation to match r326794

The above commit fixed handling overaligned TLS segments in libc's
TLS Variant I implementation, but rtld provides its own implementation
for dynamically-linked executables which lacks these fixes. Thus,
port these changes to rtld.

This was previously commited as r337978 and reverted in r338149 due to
exposing a bug the ARM rtld. This bug was fixed in r338317 by mmel.

Submitted by: James Clarke
Approved by: re (kib)
Reviewed by: kbowling
Testing by: kbowling (powerpc64), br (riscv), kevans (armv7)
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16510

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Revert r337978: Rework rtld's TLS Variant I implementation to match r326794

Michal Meloun reports that it breaks ctype (isspace()..) related
functions on armv7 so back out while we diagnose the issu

Revert r337978: Rework rtld's TLS Variant I implementation to match r326794

Michal Meloun reports that it breaks ctype (isspace()..) related
functions on armv7 so back out while we diagnose the issue.

Reported by: Michal Meloun <melounmichal@gmail.com>

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Rework rtld's TLS Variant I implementation to match r326794

The above commit fixed handling overaligned TLS segments in libc's
TLS Variant I implementation, but rtld provides its own implementation

Rework rtld's TLS Variant I implementation to match r326794

The above commit fixed handling overaligned TLS segments in libc's
TLS Variant I implementation, but rtld provides its own implementation
for dynamically-linked executables which lacks these fixes. Thus,
port these changes to rtld.

Submitted by: James Clarke
Reviewed by: kbowling
Testing byL kbowling (powerpc64), br (riscv), kevans (armv7)
Obtained from: CheriBSD
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D16510

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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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rtld: fix warnings about redundant declarations

Fix warnings about redundant declarations in rtld
when libthr in increased to WARNS=6.

Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Diff

rtld: fix warnings about redundant declarations

Fix warnings about redundant declarations in rtld
when libthr in increased to WARNS=6.

Reviewed by: kib
MFC after: 3 days
Sponsored by: Dell EMC
Differential Revision: https://reviews.freebsd.org/D10934

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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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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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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

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 run

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

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When loading dso without PT_GNU_STACK phdr, only call
__pthread_map_stacks_exec() on architectures that allow executable
stacks.

Reported and tested by: marcel (ia64)

MFC r204211:

Support the extended PLT format used when objects have more than 8192
PLT relocations on PPC32.

Support the extended PLT format used when objects have more than 8192
PLT relocations on PPC32.

Now that the kernel defines CACHE_LINE_SIZE in machine/param.h, use
that definition in the custom locking code for the run-time linker
rather than local definitions.

Pointed out by: tinderbox
MFC af

Now that the kernel defines CACHE_LINE_SIZE in machine/param.h, use
that definition in the custom locking code for the run-time linker
rather than local definitions.

Pointed out by: tinderbox
MFC after: 2 weeks

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Implement TLS relocations for powerpc.

Approved by: grehan (mentor)