rtld-elf: Pass struct tcb * around rather than struct dtv **

When this code was first written we didn't have even a struct tcb, so to
make it MI a pointer to the DTV pointer in the TCB was passed ar

rtld-elf: Pass struct tcb * around rather than struct dtv **

When this code was first written we didn't have even a struct tcb, so to
make it MI a pointer to the DTV pointer in the TCB was passed around.
Now that we have a struct tcb we can simplify the code by instead
passing around a pointer to that, and the MI code can access the tcb_dtv
member wherever it happens to be in the layout. This reduces boilerplate
in all the various callers of tls_get_addr_common/slow and makes it
clearer that tls_get_addr_common/slow are operating on the TCB, rather
than obfuscating it slightly through the double pointer.

Whilst here, clarify the comments in aarch64's TLSDESC dynamic resolver,
which were using tp without clarifying what this was for (previously a
pointer to the DTV pointer, now a pointer to the TCB, which happen to be
the same thing for Variant I TLS, and in the case of AArch64 are what
TPIDR_EL0 point to directly, with no offset/bias).

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D50591

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tls: Introduce struct dtv and struct dtv_slot

Rather than treating the DTV as a raw array of uintptr_t, use proper
struct types and gain the benefit of having different types for
different members.

tls: Introduce struct dtv and struct dtv_slot

Rather than treating the DTV as a raw array of uintptr_t, use proper
struct types and gain the benefit of having different types for
different members. In particular, the module slots now have real pointer
types so less casting is generally needed.

Note that, whilst struct dtv_slot may seem a little unnecessary, this
will help downstream in CheriBSD where we wish to be able to easily
alter the layout of a module's slot, which this helps abstract.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D50231

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rtld-elf: Pass parsed aux_info to ifunc_init

Currently we pass the raw pointer to the on-stack auxargs. This can
legitimately have fewer than AT_COUNT entries, so the use of
__min_size(AT_COUNT), i.

rtld-elf: Pass parsed aux_info to ifunc_init

Currently we pass the raw pointer to the on-stack auxargs. This can
legitimately have fewer than AT_COUNT entries, so the use of
__min_size(AT_COUNT), i.e. static AT_COUNT, is inaccurate, and also
needlessly forces the callee to iterate over the elements to find the
entry for a given type. Instead we can just pass aux_info like we use
for everything else.

Note that the argument has been left unused by every callee since its
introduction in 4352999e0e6c ("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.")

Reviewed by: kib
MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D46276

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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.

Merge ^/head r357855 through r357920.

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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MFHead@r345880

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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Merge ^/head r339813 through r340125.

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

Merge ^/head r338298 through r338391.

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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MFhead@r323635