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34 commits

Author SHA1 Message Date
Andrew Turner dd4155bec7 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
2024-05-17 09:37:12 +00:00
Andrew Turner 06db20ffec 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
2024-05-17 09:36:08 +00:00
Andrew Turner d8925a5f42 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
2024-04-12 14:30:44 +00:00
Warner Losh a6fe717c2a 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
2023-11-26 22:23:59 -07:00
Stephen J. Kiernan 95335dd3c1 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
2023-10-30 13:42:05 -04:00
Warner Losh 1d386b48a5 Remove $FreeBSD$: one-line .c pattern
Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/
2023-08-16 11:54:42 -06:00
Warner Losh b3e7694832 Remove $FreeBSD$: two-line .h pattern
Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/
2023-08-16 11:54:16 -06:00
Konstantin Belousov 283a4f4097 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
2023-06-05 22:33:17 +03:00
John Baldwin b069d3e019 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 1290d38ac5.

Reviewed by:	kib
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D37904
2023-01-04 14:55:00 -08:00
John Baldwin 8bcdb144eb 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
2021-12-09 13:23:05 -08:00
John Baldwin b928e924f7 rtld-elf: Use _get_tp in __tls_get_addr for aarch64 and riscv64.
Reviewed by:	kib
Sponsored by:	The University of Cambridge, Google Inc.
Differential Revision:	https://reviews.freebsd.org/D33047
2021-11-17 15:50:55 -08:00
Fangrui Song 8f63fa78e8 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
2021-08-16 13:55:35 +03:00
Marius Strobl b58c853edf rtld-elf(1): remove obsolete pre_init() hook
It's no longer used since 600ee699ed
and r358358 respectively.
2020-12-25 19:47:46 +01:00
Brooks Davis 29e1fceb73 Maintain a stack alignment of 16-bytes.
This violated the RISC-V 64-bit ABI.  On CheriBSD this manifested as
a trap when attempting to store 16-byte aligned types while zeroing
the stack.

Reported by:	CHERI, jrtc27
Reviewed by:	mhorne, br
Obtained from:	CheriBSD
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D26327
2020-09-04 21:46:10 +00:00
Konstantin Belousov e5c3405ce8 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
2020-04-19 09:28:59 +00:00
Konstantin Belousov c5ca0d1132 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
2020-02-13 23:42:09 +00:00
John Baldwin 15d0350503 Correct the offset of static TLS variables for Initial-Exec on RISC-V.
TP points to the start of the TLS block after the tcb, but
Obj_Entry.tlsoffset includes the tcb, so subtract the size of the tcb
to compute the offset relative to TP.

This is identical to the same fixes for powerpc in r339072 and r342671.

Reviewed by:	James Clarke
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D22661
2019-12-10 21:56:44 +00:00
Michal Meloun 4849c3a570 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
2018-12-15 10:38:07 +00:00
Alex Richardson 3ab5b6bd97 rtld-elf: fix more warnings to allow compiling with WARNS=6
Reviewed By:	kib
Approved By:	brooks (mentor)
Differential Revision: https://reviews.freebsd.org/D17154
2018-10-29 21:08:28 +00:00
Alex Richardson 903e0ffd07 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
2018-10-29 21:08:19 +00:00
Brooks Davis 17fb2856c3 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
2018-09-05 23:23:16 +00:00
Brooks Davis a5207d3ef6 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>
2018-08-21 18:22:12 +00:00
Brooks Davis 9b50d81646 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
2018-08-17 16:19:47 +00:00
Ruslan Bukin f00ebc42b5 Save and restore floating-point arguments.
Sponsored by:	DARPA, AFRL
2018-08-02 12:21:39 +00:00
Marius Strobl 41fc6f680b 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().
2018-02-03 23:14:11 +00:00
Ruslan Bukin af19cc59ca Support for v1.10 (latest) of RISC-V privilege specification.
New version is not compatible on supervisor mode with v1.9.1
(previous version).

Highlights:
    o BBL (Berkeley Boot Loader) provides no initial page tables
      anymore allowing us to choose VM, to build page tables manually
      and enable MMU in S-mode.
    o SBI interface changed.
    o GENERIC kernel.
      FDT is now chosen standard for RISC-V hardware description.
      DTB is now provided by Spike (golden model simulator). This
      allows us to introduce GENERIC kernel. However, description
      for console and timer devices is not provided in DTB, so move
      these devices temporary to nexus bus.
    o Supervisor can't access userspace by default. Solution is to
      set SUM (permit Supervisor User Memory access) bit in sstatus
      register.
    o Compressed extension is now turned on by default.
    o External GCC 7.1 compiler used.
    o _gp renamed to __global_pointer$
    o Compiler -march= string is now in use allowing us to choose
      required extensions (compressed, FPU, atomic, etc).

Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D11800
2017-08-10 14:18:09 +00:00
Eric van Gyzen 7fb37371e8 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
2017-05-26 15:55:03 +00:00
Konstantin Belousov e35ddbe448 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
2017-03-15 21:11:57 +00:00
Ed Maste eeef183376 Retire long-broken/unused static rtld support
rtld-elf has some vestigial support for building as a static executable.
r45501 introduced a partial implementation with a prescient note that it
"might never be enabled." r153515 introduced ELF symbol versioning
support, and removed part of the unused build infrastructure for static
rtld.

GNU ld populates rela relocation addends and GOT entries with the same
values, and rtld's run-time dynamic executable check relied on this.
Alternate toolchains may not populate the GOT entries, which caused
RTLD_IS_DYNAMIC to return false. Simplify rtld by just removing the
unused check.

If we want to restore static rtld support later on we ought to introduce
a build-time #ifdef flag.

PR:		214972
Reviewed by:	kan
MFC after:	1 month
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D8687
2016-12-02 14:23:26 +00:00
Konstantin Belousov d27078f990 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
2016-11-21 14:13:57 +00:00
Konstantin Belousov 4352999e0e 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
2016-11-15 09:43:26 +00:00
Ruslan Bukin e07528700a Follow r293066 adding a generalized exec hook for RISC-V as well. 2016-01-23 11:46:52 +00:00
Konstantin Belousov 9fee0541f2 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
2016-01-20 07:21:33 +00:00
Ruslan Bukin 4b1859c0e9 Add support for RISC-V architecture.
Reviewed by:	andrew, kib
Sponsored by:	DARPA, AFRL
Sponsored by:	HEIF5
Differential Revision:	https://reviews.freebsd.org/D4679
2015-12-24 15:47:51 +00:00