The _dl_non_dynamic_init does not parse LD_PROFILE, which does not
enable profile for dlopen objects. Since dlopen is deprecated for
static objects, it is better to remove the support.
It also allows to trim down libc.a of profile support.
Checked on x86_64-linux-gnu.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
The sparc ABI has multiple cases on how to handle JMP_SLOT relocations,
(sparc_fixup_plt/sparc64_fixup_plt). For BINDNOW, _dl_audit_symbind
will be responsible to setup the final relocation value; while for
lazy binding _dl_fixup/_dl_profile_fixup will call the audit callback
and tail cail elf_machine_fixup_plt (which will call
sparc64_fixup_plt).
This patch fixes by issuing the SPARC specific routine on bindnow and
forwarding the audit value to elf_machine_fixup_plt for lazy resolution.
It fixes the la_symbind for bind-now tests on sparc64 and sparcv9:
elf/tst-audit24a
elf/tst-audit24b
elf/tst-audit24c
elf/tst-audit24d
Checked on sparc64-linux-gnu and sparcv9-linux-gnu.
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
The rtld-audit interfaces introduces a slowdown due to enabling
profiling instrumentation (as if LD_AUDIT implied LD_PROFILE).
However, instrumenting is only necessary if one of audit libraries
provides PLT callbacks (la_pltenter or la_pltexit symbols). Otherwise,
the slowdown can be avoided.
The following patch adjusts the logic that enables profiling to iterate
over all audit modules and check if any of those provides a PLT hook.
To keep la_symbind to work even without PLT callbacks, _dl_fixup now
calls the audit callback if the modules implements it.
Co-authored-by: Alexander Monakov <amonakov@ispras.ru>
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
It consolidates the code required to call la_pltexit audit
callback.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
It consolidates the code required to call la_pltenter audit
callback.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
It consolidates the code required to call la_symbind{32,64} audit
callback.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Before to 490e6c62aa ('elf: Avoid nested functions in the loader
[BZ #27220]'), elf_get_dynamic_info() was defined twice on rtld.c: on
the first dynamic-link.h include and later within _dl_start(). The
former definition did not define DONT_USE_BOOTSTRAP_MAP and it is used
on setup_vdso() (since it is a global definition), while the former does
define DONT_USE_BOOTSTRAP_MAP and it is used on loader self-relocation.
With the commit change, the function is now included and defined once
instead of defined as a nested function. So rtld.c defines without
defining RTLD_BOOTSTRAP and it brokes at least powerpc32.
This patch fixes by moving the get-dynamic-info.h include out of
dynamic-link.h, which then the caller can corirectly set the expected
semantic by defining STATIC_PIE_BOOTSTRAP, RTLD_BOOTSTRAP, and/or
RESOLVE_MAP.
It also required to enable some asserts only for the loader bootstrap
to avoid issues when called from setup_vdso().
As a side note, this is another issues with nested functions: it is
not clear from pre-processed output (-E -dD) how the function will
be build and its semantic (since nested function will be local and
extra C defines may change it).
I checked on x86_64-linux-gnu (w/o --enable-static-pie),
i686-linux-gnu, powerpc64-linux-gnu, powerpc-linux-gnu-power4,
aarch64-linux-gnu, arm-linux-gnu, sparc64-linux-gnu, and
s390x-linux-gnu.
Reviewed-by: Fangrui Song <maskray@google.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master
The existing macros are fragile and expect local variables with a
certain name. Fix this by defining them as functions with default
implementation in a new header dl-runtime.h which arches can override
if need be.
This came up during ARC port review, hence the need for argument pltgot
in reloc_index() which is not needed by existing ports.
This patch potentially only affects hppa/x86 ports,
build tested for both those configs and a few more.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To improve GCC 10 compatibility, it is necessary to remove the l_audit
zero-length array from the end of struct link_map. In preparation of
that, this commit introduces an accessor function for the audit state,
so that it is possible to change the representation of the audit state
without adjusting the code that accesses it.
Tested on x86_64-linux-gnu. Built on i686-gnu.
Change-Id: Id815673c29950fc011ae5301d7cde12624f658df
There is a data-dependency between the fields of struct l_reloc_result
and the field used as the initialization guard. Users of the guard
expect writes to the structure to be observable when they also observe
the guard initialized. The solution for this problem is to use an acquire
and release load and store to ensure previous writes to the structure are
observable if the guard is initialized.
The previous implementation used DL_FIXUP_VALUE_ADDR (l_reloc_result->addr)
as the initialization guard, making it impossible for some architectures
to load and store it atomically, i.e. hppa and ia64, due to its larger size.
This commit adds an unsigned int to l_reloc_result to be used as the new
initialization guard of the struct, making it possible to load and store
it atomically in all architectures. The fix ensures that the values
observed in l_reloc_result are consistent and do not lead to crashes.
The algorithm is documented in the code in elf/dl-runtime.c
(_dl_profile_fixup). Not all data races have been eliminated.
Tested with build-many-glibcs and on powerpc, powerpc64, and powerpc64le.
[BZ #23690]
* elf/dl-runtime.c (_dl_profile_fixup): Guarantee memory
modification order when accessing reloc_result->addr.
* include/link.h (reloc_result): Add field init.
* nptl/Makefile (tests): Add tst-audit-threads.
(modules-names): Add tst-audit-threads-mod1 and
tst-audit-threads-mod2.
Add rules to build tst-audit-threads.
* nptl/tst-audit-threads-mod1.c: New file.
* nptl/tst-audit-threads-mod2.c: Likewise.
* nptl/tst-audit-threads.c: Likewise.
* nptl/tst-audit-threads.h: Likewise.
Signed-off-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Wrap symbol address run-time calculation into a macro and use it
throughout, replacing inline calculations.
There are a couple of variants, most of them different in a functionally
insignificant way. Most calculations are right following RESOLVE_MAP,
at which point either the map or the symbol returned can be checked for
validity as the macro sets either both or neither. In some places both
the symbol and the map has to be checked however.
My initial implementation therefore always checked both, however that
resulted in code larger by as much as 0.3%, as many places know from
elsewhere that no check is needed. I have decided the size growth was
unacceptable.
Having looked closer I realized that it's the map that is the culprit.
Therefore I have modified LOOKUP_VALUE_ADDRESS to accept an additional
boolean argument telling it to access the map without checking it for
validity. This in turn has brought quite nice results, with new code
actually being smaller for i686, and MIPS o32, n32 and little-endian n64
targets, unchanged in size for x86-64 and, unusually, marginally larger
for big-endian MIPS n64, as follows:
i686:
text data bss dec hex filename
152255 4052 192 156499 26353 ld-2.27.9000-base.so
152159 4052 192 156403 262f3 ld-2.27.9000-elf-symbol-value.so
MIPS/o32/el:
text data bss dec hex filename
142906 4396 260 147562 2406a ld-2.27.9000-base.so
142890 4396 260 147546 2405a ld-2.27.9000-elf-symbol-value.so
MIPS/n32/el:
text data bss dec hex filename
142267 4404 260 146931 23df3 ld-2.27.9000-base.so
142171 4404 260 146835 23d93 ld-2.27.9000-elf-symbol-value.so
MIPS/n64/el:
text data bss dec hex filename
149835 7376 408 157619 267b3 ld-2.27.9000-base.so
149787 7376 408 157571 26783 ld-2.27.9000-elf-symbol-value.so
MIPS/o32/eb:
text data bss dec hex filename
142870 4396 260 147526 24046 ld-2.27.9000-base.so
142854 4396 260 147510 24036 ld-2.27.9000-elf-symbol-value.so
MIPS/n32/eb:
text data bss dec hex filename
142019 4404 260 146683 23cfb ld-2.27.9000-base.so
141923 4404 260 146587 23c9b ld-2.27.9000-elf-symbol-value.so
MIPS/n64/eb:
text data bss dec hex filename
149763 7376 408 157547 2676b ld-2.27.9000-base.so
149779 7376 408 157563 2677b ld-2.27.9000-elf-symbol-value.so
x86-64:
text data bss dec hex filename
148462 6452 400 155314 25eb2 ld-2.27.9000-base.so
148462 6452 400 155314 25eb2 ld-2.27.9000-elf-symbol-value.so
[BZ #19818]
* sysdeps/generic/ldsodefs.h (LOOKUP_VALUE_ADDRESS): Add `set'
parameter.
(SYMBOL_ADDRESS): New macro.
[!ELF_FUNCTION_PTR_IS_SPECIAL] (DL_SYMBOL_ADDRESS): Use
SYMBOL_ADDRESS for symbol address calculation.
* elf/dl-runtime.c (_dl_fixup): Likewise.
(_dl_profile_fixup): Likewise.
* elf/dl-symaddr.c (_dl_symbol_address): Likewise.
* elf/rtld.c (dl_main): Likewise.
* sysdeps/aarch64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/alpha/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/arm/dl-machine.h (elf_machine_rel): Likewise.
(elf_machine_rela): Likewise.
* sysdeps/hppa/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/hppa/dl-symaddr.c (_dl_symbol_address): Likewise.
* sysdeps/i386/dl-machine.h (elf_machine_rel): Likewise.
(elf_machine_rela): Likewise.
* sysdeps/ia64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/m68k/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/microblaze/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/mips/dl-machine.h (ELF_MACHINE_BEFORE_RTLD_RELOC):
Likewise.
(elf_machine_reloc): Likewise.
(elf_machine_got_rel): Likewise.
* sysdeps/mips/dl-trampoline.c (__dl_runtime_resolve): Likewise.
* sysdeps/nios2/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/riscv/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_rela):
Likewise.
* sysdeps/tile/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/x86_64/dl-machine.h (elf_machine_rela): Likewise.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
ELFv2 functions with localentry:0 are those with a single entry point,
ie. global entry == local entry, that have no requirement on r2 or
r12 and guarantee r2 is unchanged on return. Such an external
function can be called via the PLT without saving r2 or restoring it
on return, avoiding a common load-hit-store for small functions.
This patch implements the ld.so changes necessary for this
optimization. ld.so needs to check that an optimized plt call
sequence is in fact calling a function implemented with localentry:0,
end emit a fatal error otherwise.
The elf/testobj6.c change is to stop "error while loading shared
libraries: expected localentry:0 `preload'" when running
elf/preloadtest, which we'd get otherwise.
* elf/elf.h (PPC64_OPT_LOCALENTRY): Define.
* sysdeps/alpha/dl-machine.h (elf_machine_fixup_plt): Add
refsym and sym parameters. Adjust callers.
* sysdeps/aarch64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/arm/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/generic/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/hppa/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/i386/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/ia64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/m68k/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/microblaze/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/mips/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/nios2/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_fixup_plt):
Likewise.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sh/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/tile/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/x86_64/dl-machine.h (elf_machine_fixup_plt): Likewise.
* sysdeps/powerpc/powerpc64/dl-machine.c (_dl_error_localentry): New.
(_dl_reloc_overflow): Increase buffser size. Formatting.
* sysdeps/powerpc/powerpc64/dl-machine.h (ppc64_local_entry_offset):
Delete reloc param, add refsym and sym. Check optimized plt
call stubs for localentry:0 functions. Adjust callers.
(elf_machine_fixup_plt, elf_machine_plt_conflict): Add refsym
and sym parameters. Adjust callers.
(_dl_reloc_overflow): Move attribute.
(_dl_error_localentry): Declare.
* elf/dl-runtime.c (_dl_fixup): Save original sym. Pass
refsym and sym to elf_machine_fixup_plt.
* elf/testobj6.c (preload): Call printf.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch replaces its use for _dl_mcount with use of rtld_hidden_def /
rtld_hidden_proto.
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-profile.c (_dl_mcount): Use rtld_hidden_def instead of
INTDEF.
* sysdeps/generic/ldsodefs.h (_dl_mcount_internal): Remove
declaration.
(_dl_mcount): Use rtld_hidden_proto.
* elf/dl-runtime.c (_dl_profile_fixup): Don't use INTUSE with
_dl_mcount.
* elf/rtld.c (_rtld_global_ro): Likewise.
This patch defines ELF_MACHINE_NO_RELA on all architectures. Tested
only on x86_64 to verify that the sources before and after are
identical except for two instructions that pass the current line
number in dl-machine.h to assert_fail.
SSE registers are used for passing parameters and must be preserved
in runtime relocations. This is inside ld.so enforced through the
tests in tst-xmmymm.sh. But the malloc routines used after startup
come from libc.so and can be arbitrarily complex. It's overkill
to save the SSE registers all the time because of that. These calls
are rare. Instead we save them on demand. The new infrastructure
put in place in this patch makes this possible and efficient.
* elf/dl-runtime.c (_dl_fixup): Use DL_FIXUP_VALUE_ADDR to access
result of lookup to make call to implement STT_GNU_IFUNC.
(_dl_profile_fixup): Likewise.
Patch by H.J. Lu <hjl.tools@gmail.com>.
(reloc_index): Define.
(_dl_fixup): Rename reloc_offset parameter to reloc_arg.
(_dl_fixup_profile): Likewise. Use reloc_index instead of
computing index from reloc_offset.
(_dl_call_pltexit): Likewise.
* sysdeps/x86_64/dl-trampoline.S (_dl_runtime_resolve): Just pass
the relocation index to _dl_fixup.
(_dl_runtime_profile): Likewise for _dl_fixup_profile and
_dl_call_pltexit.
* sysdeps/x86_64/dl-runtime.c: New file.
* elf/dl-runtime.c (_dl_fixup, _dl_profile_fixup): Or in
DL_LOOKUP_GSCOPE_LOCK into flags after THREAD_GSCOPE_SET_FLAG ().
* elf/dl-sym.c (do_sym): Likewise.
* include/link.h (struct link_map): Add l_serial field.
* elf/dl-object.c (_dl_new_object): Initialize l_serial.
* elf/dl-lookup.c (add_dependency): Add flags argument.
Remember map->l_serial, if DL_LOOKUP_GSCOPE_LOCK is among
flags, use THREAD_GSCOPE_RESET_FLAG before and
THREAD_GSCOPE_SET_FLAG after
__rtld_lock_lock_recursive (GL(dl_load_lock)) to avoid deadlock.
Don't dereference map until it has been found on some list.
If map->l_serial changed, return -1.
2007-06-13 Jakub Jelinek <jakub@redhat.com>
* include/link.h: Don't include rtld-lowlevel.h.
(struct link_map): Remove l_scope_lock.
* sysdeps/generic/ldsodefs.h: Don't include rtld-lowlevel.h.
(_dl_scope_free_list): New field (variable) in _rtld_global.
(DL_LOOKUP_SCOPE_LOCK): Remove.
(_dl_scope_free): New prototype.
* elf/dl-runtime.c (_dl_fixup): Don't use __rtld_mrlock_*lock.
Don't pass DL_LOOKUP_SCOPE_LOCK to _dl_lookup_symbol_x.
(_dl_profile_fixup): Likewise.
* elf/dl-sym.c (do_sym): Likewise. Use wrapped _dl_lookup_symbol_x
whenever !RTLD_SINGLE_THREAD_P, use THREAD_GSCOPE_SET_FLAG and
THREAD_GSCOPE_RESET_FLAG around it.
* elf/dl-close.c (_dl_close_worker): Don't use
__rtld_mrlock_{change,done}. Call _dl_scope_free on the old
scope. Make sure THREAD_GSCOPE_WAIT () happens if any old
scopes were queued or if l_scope_mem has been abandoned.
* elf/dl-open.c (_dl_scope_free): New function.
(dl_open_worker): Use it. Don't use __rtld_mrlock_{change,done}.
* elf/dl-support.c (_dl_scope_free_list): New variable.
* elf/dl-lookup.c (add_dependency): Remove flags argument.
Remove DL_LOOKUP_SCOPE_LOCK handling.
(_dl_lookup_symbol_x): Adjust caller. Remove DL_LOOKUP_SCOPE_LOCK
handling.
* elf/dl-object.c (_dl_new_object): Don't use
__rtld_mrlock_initialize.
2007-06-19 Ulrich Drepper <drepper@redhat.com>
global scope, wait for all lookups to finish afterwards.
* elf/dl-open.c (add_to_global): When global scope array must
grow, allocate a new one and free old array only after all
lookups finish.
* elf/dl-runtime.c (_dl_fixup): Protect using global scope.
(_dl_lookup_symbol_x): Likewise.
* elf/dl-support.c: Define _dl_wait_lookup_done.
* sysdeps/generic/ldsodefs.h (struct rtld_global): Add
_dl_wait_lookup_done.
* elf/dl-lookup.c (add_dependency): If scope map is locked, unlock
it before getting dl_load_lock and then relock.
(_dl_lookup_symbol_x): Pass flags to add_dependency.
When rerunning _dl_lookup_symbol_x, compute symbol_scope again in
case we unlocked the scope.
* elf/dl-runtime.c (_dl_fixup): Pass DL_LOOKUP_SCOPE_LOCK to
_dl_lookup_symbol_x in case we locked the scope.
(_dl_profile_fixup): Likewise.
* elf/dl-sym.c (do_sym): In flags passed to call_dl_lookup, also
set DL_LOOKUP_SCOPE_LOCK.
