rtld: ignore load_filtees() calls if we already loading filtees for the obj

in addition to avoiding it for already loaded filtees. Issue is that
during load, rtld needs to resolve some special ABI s

rtld: ignore load_filtees() calls if we already loading filtees for the obj

in addition to avoiding it for already loaded filtees. Issue is that
during load, rtld needs to resolve some special ABI symbols, like
executable stack fixer and static TLS initializer, which might trigger
recursion.

Example is libthr which is filter for libsys, and which exports
__pthread_distribute_static_tls.

Tested by: kevans, krion
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D43858

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RTLD_DEEPBIND: make lookup not just symbolic, but walk all refobj' DAGs

before starting the walk over the global list. Effectively we visit
needed objects first as well, instead of just the object

RTLD_DEEPBIND: make lookup not just symbolic, but walk all refobj' DAGs

before starting the walk over the global list. Effectively we visit
needed objects first as well, instead of just the object itself.
This seems to better match the semantic offered by the glibc flag.

Reported by: kevans
PR: 275393
Reviewed by: kevans
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D42841

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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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rtld: switch from malloc_aligned() to __crt_aligned_alloc()

Use regular free(), since it works now.

Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision:

rtld: switch from malloc_aligned() to __crt_aligned_alloc()

Use regular free(), since it works now.

Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D41150

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Remove $FreeBSD$: two-line .h pattern

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

rtld: remove dup __crt_malloc prototypes

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D41150

rtld: do not allow both dynamic DTV index and static TLS offset

If we are allocating static offset for an object with dynamic index,
return failure. In the opposite case, if dynamic index is reques

rtld: do not allow both dynamic DTV index and static TLS offset

If we are allocating static offset for an object with dynamic index,
return failure. In the opposite case, if dynamic index is requested for
statically allocated TLS area, directly use the offset instead of
setting the index.

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: 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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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: fix SysV hash function overflow

Quoting from https://maskray.me/blog/2023-04-12-elf-hash-function:

The System V Application Binary Interface (generic ABI) specifies the
ELF object file format

rtld: fix SysV hash function overflow

Quoting from https://maskray.me/blog/2023-04-12-elf-hash-function:

The System V Application Binary Interface (generic ABI) specifies the
ELF object file format. When producing an output executable or shared
object needing a dynamic symbol table (.dynsym), a linker generates a
.hash section with type SHT_HASH to hold a symbol hash table. A DT_HASH
tag is produced to hold the address of .hash.

The function is supposed to return a value no larger than 0x0fffffff.
Unfortunately, there is a bug. When unsigned long consists of more than
32 bits, the return value may be larger than UINT32_MAX. For instance,
elf_hash((const unsigned char *)"\xff\x0f\x0f\x0f\x0f\x0f\x12") returns
0x100000002, which is clearly unintended, as the function should behave
the same way regardless of whether long represents a 32-bit integer or
a 64-bit integer.

Reviewed by: kib, Fangrui Song
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D39517

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Have rtld query the page size from the kernel

To allow for a dynamic page size on arm64 have the runtime linker
query the kernel for the currentl page size.

Reviewed by: kib
Sponsored by: The FreeB

Have rtld query the page size from the kernel

To allow for a dynamic page size on arm64 have the runtime linker
query the kernel for the currentl page size.

Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34765

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rtld: remove mips-specific cases from generic code

Reviewed by: imp
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D33763

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: extract header validation into new helper check_elf_headers()

Reviewed by: emaste
Discussed with: jrtc27
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revi

rtld: extract header validation into new helper check_elf_headers()

Reviewed by: emaste
Discussed with: jrtc27
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D32960

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rtld: Support DT_RELR relative relocation format

PIE and shared objects usually have many relative relocations. In
2017/2018, a compact relative relocation format RELR was proposed on
https://groups

rtld: Support DT_RELR relative relocation format

PIE and shared objects usually have many relative relocations. In
2017/2018, a compact relative relocation format RELR was proposed on
https://groups.google.com/g/generic-abi/c/bX460iggiKg/m/GxjM0L-PBAAJ
("Proposal for a new section type SHT_RELR") and is a pre-standard.
RELR usually takes 3% or smaller space than R_*_RELATIVE relocations.
The virtual memory size of a mostly statically linked PIE is typically
5~10% smaller.

ld.lld --pack-dyn-relocs=relr emits RELR relocations. DT_RELR has been
adopted by Android bionic, Linux kernel's arm64 port, Chrome OS (patched
glibc).

This patch adds DT_RELR support to FreeBSD rtld-elf.

MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D32524

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rtld: unstaticise lockinfo and obj_from_addr()

Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29633

rtld: avoid recursing on rtld_bind_lock for write

This fixes a regression in d36d6816151705907393889, where the call to
__tls_get_address() was performed under rtld_bind_lock write-locked.
Instead u

rtld: avoid recursing on rtld_bind_lock for write

This fixes a regression in d36d6816151705907393889, where the call to
__tls_get_address() was performed under rtld_bind_lock write-locked.
Instead use tls_get_addr_slow() directly, with locked = true.

Reported by: jkim, many others
Tested by: jkim, bdragon (powerpc), mhorne (riscv)
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D29623

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

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

Do not allow to load ET_DYN object with DF_1_PIE flag set.

Linkers are supposed to mark PIE binaries with DF_1_PIE, such binary
cannot be correctly and usefully loaded neither by dlopen(3) nor as a

Do not allow to load ET_DYN object with DF_1_PIE flag set.

Linkers are supposed to mark PIE binaries with DF_1_PIE, such binary
cannot be correctly and usefully loaded neither by dlopen(3) nor as a
dependency of other object. For instance, we cannot do anything
useful with COPY relocations, among other things.

Glibc already added similar restriction.

Requested and reviewed by: emaste
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D25086

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Implement RTLD_DEEPBIND.

PR: 246462
Tested by: Martin Birgmeier <d8zNeCFG@aon.at>
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D24841

rtld: ignore static TLS segments when tracing.

For PIE binaries, ldd(1) performs dlopen(RTLD_TRACE) on the binary.
It is legal for binary to use initial exec TLS mode, but when such
binary (actually

rtld: ignore static TLS segments when tracing.

For PIE binaries, ldd(1) performs dlopen(RTLD_TRACE) on the binary.
It is legal for binary to use initial exec TLS mode, but when such
binary (actually dso) is dlopened, we might not have enough free space
in the finalized static TLS segment. Make ldd operational by skipping
TLS space allocation, we are not going to execute any code from the
dso anyway.

Reported by: tobik
PR: 245677
Sponsored by: The FreeBSD Foundation
MFC after: 1 week

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Make p_vaddr % p_align == p_offset % p_align for (some) TLS segments.

See https://sourceware.org/bugzilla/show_bug.cgi?id=24606 for the test case.
See https://reviews.llvm.org/D64930 for the backgro

Make p_vaddr % p_align == p_offset % p_align for (some) TLS segments.

See https://sourceware.org/bugzilla/show_bug.cgi?id=24606 for the test case.
See https://reviews.llvm.org/D64930 for the background and more discussion.

Also this fixes another bug in malloc_aligned() where total size of
the allocated memory might be not enough to fit the aligned requested
block after the initial pointer is incremented by the pointer size.

Reviewed by: bdragon
Tested by: antoine (exp-run PR 244866), bdragon, emaste
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D21163

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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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Use sigfastblock(2) in rtld.

This allows for rtld to not issue two sigprocmask(2) syscalls for each
symbol binding operation in single-threaded processes. Rtld needs to
block signals as part of loc

Use sigfastblock(2) in rtld.

This allows for rtld to not issue two sigprocmask(2) syscalls for each
symbol binding operation in single-threaded processes. Rtld needs to
block signals as part of locking to ensure signal safety of the bind
process, because signal handlers might need to lazily resolve symbol
references.

As result, number of syscalls issued on startup by simple programs not
using libthr, is typically reduced 2x. For instance, for hello world,
I see:
non-sigfastblock
# (truss ./hello > /dev/null) |& wc -l
63
sigfastblock
# (truss ./hello > /dev/null) |& wc -l
37

Tested by: pho
Disscussed with: cem, emaste, jilles
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D12773

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rtld(1): Do booleans like C99

Reviewed by: kib, rlibby
Differential Revision: https://reviews.freebsd.org/D22964