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.
On s390, the current prelink undo code in elf_machine_lazy_rel()
has the requirement, that the plt stubs use the first got slots
after the 3 reserved ones.
In case of undoing prelink, the plt got slots are reset to the correct
addresses whithin the corresponding plt-stub. Therefore the address
is calculated by the address of the first plt-stub-address which
was written by prelink (see l->l_mach.plt) to got[1] and index of
current relocation multiplied with 32 (=size of one plt slot).
The index was calculated with ¤t-got-slot - &got[3].
This patch removes the requirement, that the plt-got-slots are
starting at got[3]. The index is now calculated with
¤t-reloc - &reloc[0]. The first struct Elf64_Rela is stored
at DT_JMPREL.
This patch is needed to prepare for partial relro support.
Ulrich Weigand suggested this approach to use DT_JMPREL - Thanks.
ChangeLog:
* sysdeps/s390/linkmap.h (struct link_map_machine):
Remove member gotplt and add member jmprel.
* sysdeps/s390/s390-32/dl-machine.h
(elf_machine_runtime_setup): Setup member jmprel with DT_JMPREL
instead of gotplt with &got[3].
(elf_machine_lazy_rel): Calculate address with reloc and jmprel.
* sysdeps/s390/s390-64/dl-machine.h: Likewise.
On s390, no fpr/vrs were saved while resolving a symbol
via _dl_runtime_resolve/_dl_runtime_profile.
According to the abi, the fpr-arguments are defined as call clobbered.
In leaf-functions, gcc 4.9 and newer can use fprs for saving/restoring gprs
instead of saving them to the stack.
If gcc do this in one of the resolver-functions, then the floating point
arguments of a library-function are invalid for the first library-function-call.
Thus, this patch saves/restores the fprs around the resolving code.
The same could occur for vector registers. Furthermore an ifunc-resolver
could also clobber the vector/floating point argument registers.
Thus this patch provides the further variants _dl_runtime_resolve_vx/
_dl_runtime_profile_vx, which are used if the kernel claims, that
we run on a machine with vector registers.
Furthermore, if _dl_runtime_profile calls _dl_call_pltexit,
the pointers to inregs-/outregs-structs were setup invalid.
Now they point to the correct location in the stack-frame.
Before branching back to the caller, the return values are now
restored instead of containing the return values of the
_dl_call_pltexit() call.
On s390-32, an endless loop occurs if _dl_call_pltexit() should be called.
Now, this code-path branches to this function instead of just after the
preceding basr-instruction.
ChangeLog:
* sysdeps/s390/s390-32/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-32/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
if _dl_call_pltexit is called.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
* sysdeps/s390/s390-64/dl-trampoline.S: Include dl-trampoline.h twice
to create a non-vector/vector version for _dl_runtime_resolve and
_dl_runtime_profile. Move implementation to ...
* sysdeps/s390/s390-64/dl-trampoline.h: ... here.
(_dl_runtime_resolve) Save and restore fpr/vrs.
(_dl_runtime_profile) Save and restore vrs and fix some issues
* sysdeps/s390/s390-64/dl-machine.h: (elf_machine_runtime_setup):
Choose the correct resolver function if running on a machine with vx.
The s390 ABI requires the stack pointer to be aligned at 8-bytes.
When a program is invoked as an argument to the dynamic linker,
_dl_start_user adjusts the stack to remove the dynamic linker
arguments so that the program sees only its name and arguments. This
may result in the stack being misaligned since each argument shift is
only a word and not a double-word.
This is now fixed shifting argv and envp down instead of shifting argc
up and reclaiming the stack. This requires _dl_argv to be adjusted
and hence, is no longer relro.
Continuing the removal of the obsolete INTDEF / INTUSE mechanism, this
patch eliminates its use for _dl_init. Since _dl_init was already
declared with hidden visibility, creating a second hidden alias for it
was completely pointless, so this patch replaces all uses of
_dl_init_internal with plain _dl_init instead of using hidden_proto /
hidden_def (which are only needed when you want a hidden alias for a
non-hidden symbol; it's quite possible there are cases where they are
used but don't need to be because the symbol in question is not part
of the public ABI and is only used within a single library, so using
attributes_hidden instead would suffice).
Tested for x86_64 that installed stripped shared libraries are
unchanged by the patch.
[BZ #14132]
* elf/dl-init.c (_dl_init): Don't use INTDEF.
* sysdeps/aarch64/dl-machine.h (RTLD_START): Use _dl_init instead
of _dl_init_internal.
* sysdeps/alpha/dl-machine.h (RTLD_START): Likewise.
* sysdeps/arm/dl-machine.h (RTLD_START): Likewise.
* sysdeps/hppa/dl-machine.h (RTLD_START): Likewise.
* sysdeps/i386/dl-machine.h (RTLD_START): Likewise.
* sysdeps/ia64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/m68k/dl-machine.h (RTLD_START): Likewise.
* sysdeps/microblaze/dl-machine.h (RTLD_START): Likewise.
* sysdeps/mips/dl-machine.h (RTLD_START): Likewise.
* sysdeps/powerpc/powerpc32/dl-start.S (_start): Likewise.
* sysdeps/s390/s390-32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/s390/s390-64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sh/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc32/dl-machine.h (RTLD_START): Likewise.
* sysdeps/sparc/sparc64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/tile/dl-start.S (_start): Likewise.
* sysdeps/x86_64/dl-machine.h (RTLD_START): Likewise.
* sysdeps/x86_64/x32/dl-machine.h (RTLD_START): 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.
Resolves: #15465
The program name may be unavailable if the user application tampers
with argc and argv[]. Some parts of the dynamic linker caters for
this while others don't, so this patch consolidates the check and
fallback into a single macro and updates all users.
Add support for STT_GNU_IFUNC symbols and the new R_390_IRELATIVE
relocation. Provide optimized version of memcpy, memset, and memcmp
for z10 and z196.
2003-07-31 Jakub Jelinek <jakub@redhat.com>
* dlfcn/dlerror.c (once): New.
(dlerror): Call __libc_once.
(_dlerror_run): Remove once.
2003-07-31 Jakub Jelinek <jakub@redhat.com>
* sysdeps/unix/sysv/linux/ia64/bits/sigcontext.h (struct sigcontext):
Sync with 2.5.7 and 2.5.73 kernel changes.
2003-07-31 Jakub Jelinek <jakub@redhat.com>
* dlfcn/eval.c (funcall): Add noinline attribute to shut up warnings.
* elf/rtld.c (dl_main): Cast ElfW(Addr) arguments with %Zx/%Zd
formats to size_t.
* elf/dl-lookup.c (_dl_debug_bindings): Likewise.
* elf/tst-tls6.c (do_test): Use %zd format for l_tls_modid.
* elf/tst-tls8.c (do_test): Use %zd format for modid1 and modid2.
* gmon/tst-sprofil.c (main): Add parens to shut up warning.
* iconv/tst-iconv3.c (main): Use %td instead of %zd for pointer
difference argument.
* stdio-common/tst-wc-printf.c (main): Cast arguments with %C
format to wint_t.
* stdlib/tst-limits.c (main): For WORD_BIT and LONG_BIT, use
%d format and cast expected value to int.
* sysdeps/generic/libc-start.c (STATIC): Add
__attribute__((always_inline) if LIBC_START_MAIN is already defined.
* sysdeps/powerpc/fpu/w_sqrt.c (a_nan, a_inf): Change from uint32_t
to ieee_float_shape_type.
(__sqrt): Avoid type punning.
* sysdeps/powerpc/fpu/w_sqrtf.c (a_nan, a_inf): Change from uint32_t
to ieee_float_shape_type.
(__sqrtf): Avoid type punning.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_rela): Don't define
refsym if in dl-conflict.c.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_rela): Likewise.
* sysdeps/unix/sysv/linux/i386/semctl.c (union semun): Add __old_buf.
(__new_semctl): Shut up warning.
* sysdeps/unix/sysv/linux/semctl.c (union semun): Add __old_buf.
(__new_semctl): Shut up warning.
* sysdeps/unix/sysv/linux/shmctl.c (__new_shmctl): Wrap long lines.
Change old into union of __old_shmid_ds and __old_shminfo structs.
Adjust all users.
* wcsmbs/wcsmbs-tst1.c (main): Cast arguments with %C format to wint_t.
2003-07-31 Jakub Jelinek <jakub@redhat.com>
* sysdeps/unix/sysv/linux/utimes.c (__utimes): Fix actime and
modtime computation.
* sysdeps/unix/sysv/linux/futimes.c (__futimes): Likewise.
* sysdeps/posix/utimes.c (__utimes): Likewise.
2001-12-11 Jakub Jelinek <jakub@redhat.com>
* elf/Makefile (dl-routines): Add conflict.
(rtld-ldscript-in, rtld-ldscript, rtld-parms): Remove.
(ld.so): Add _begin local symbol.
* elf/elf.h (DT_VALTAGIDX, DT_VALNUM, DT_ADDRTAGIDX, DT_ADDRNUM):
Define.
* elf/dl-deps.c (_dl_build_local_scope): New.
(_dl_map_object_deps): If LD_TRACE_PRELINKING, compute local scopes
of all libraries.
* elf/do-rel.h (VALIDX): Define.
(elf_dynamic_do_rel): If ELF_MACHINE_PLT_REL is defined, don't do
lazy binding for RELA. If DT_GNU_PRELINKED, DT_RELACOUNT relocations
can be skipped.
* elf/dl-conflict.c: New file.
* elf/dl-lookup.c (_dl_debug_bindings): New.
(_dl_lookup_symbol): Use _dl_debug_bindings. Reference_name is always
non-NULL.
(_dl_lookup_symbol_skip): Likewise.
(_dl_lookup_versioned_symbol): Likewise.
(_dl_lookup_versioned_symbol_skip): Likewise.
* elf/dl-runtime.c (PLTREL): If ELF_MACHINE_PLT_REL is defined,
define to ElfW(Rel).
* elf/dynamic-link.h (elf_get_dynamic_info): Record selected dynamic
tags in the DT_VALRNGLO..DT_VALRNGHI and DT_ADDRRNGLO..DT_ADDRRNGHI
ranges.
Don't adjust address dynamic tags if l_addr is 0.
* elf/rtld.c (_dl_trace_prelink, _dl_trace_prelink_map): New variables.
(_dl_start): Skip ELF_DYNAMIC_RELOCATE if ld.so is prelinked.
(VALIDX, ADDRIDX): Define.
(_dl_start_final): Initialize _dl_rtld_map's l_map_start and l_map_end.
(dl_main): Print library list for LD_TRACE_PRELINKING.
If prelinking information can be used, skip relocating libraries and
call _dl_resolve_conflicts instead.
(process_envvars): Handle LD_TRACE_PRELINKING envvar.
* elf/dl-load.c (_dl_map_object): Don't create fake libs
if LD_TRACE_PRELINKING.
* include/link.h (struct link_map) [l_info]: Add DT_VALNUM
+ DT_ADDRNUM.
* sysdeps/generic/ldsodefs.h (_dl_trace_prelink_map): New declaration.
(DL_DEBUG_PRELINK): Define.
(_dl_resolve_conflicts): Add prototype.
* sysdeps/alpha/dl-machine.h (elf_machine_runtime_setup): Reinitialize
.plt for prelinked libraries where prelinking info cannot be used.
(elf_machine_rela): If relocating R_ALPHA_JMP_SLOT in .gnu.conflict
section, use RESOLVE_CONFLICT_FIND_MAP to find out reloc's link_map.
* sysdeps/arm/bits/link.h: New file.
* sysdeps/arm/dl-machine.h (elf_machine_runtime_setup): Save original
content of .got[1].
(ELF_MACHINE_NO_RELA): Only define if RTLD_BOOTSTRAP.
(ELF_MACHINE_PLT_REL): Define.
(elf_machine_rela, elf_machine_rela_relative): New.
(elf_machine_lazy_rel): Reinitialize R_ARM_JUMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
* sysdeps/i386/bits/link.h: New file.
* sysdeps/i386/dl-machine.h (elf_machine_runtime_setup): Save original
content of .got[1].
(ELF_MACHINE_NO_RELA): Only define if RTLD_BOOTSTRAP.
(ELF_MACHINE_PLT_REL): Define.
(elf_machine_rela, elf_machine_rela_relative): New.
(elf_machine_lazy_rel): Reinitialize R_386_JUMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
* sysdeps/powerpc/dl-machine.h (elf_machine_rela): If relocating
conflicts, skip finaladdr computation. Use RESOLVE_CONFLICT_FIND_MAP
to find out map for R_PPC_JMP_SLOT relocs.
* sysdeps/sparc/sparc32/dl-machine.h (VALIDX): Define.
(OPCODE_BA): Define.
(elf_machine_runtime_setup): Reinitialize .plt for prelinked
libraries where prelinking info cannot be used.
(sparc_fixup_plt): Renamed from elf_machine_fixup_plt.
(elf_machine_fixup_plt): Call sparc_fixup_plt.
(elf_machine_rela): Set value to 0 if relocating conflicts.
Call sparc_fixup_plt for R_SPARC_JMP_SLOT.
* sysdeps/sparc/sparc64/dl-machine.h (VALIDX): Define.
(sparc64_fixup_plt): Fix a typo.
(elf_machine_rela): Set value to 0 if relocating conflicts.
Handle R_SPARC_JMP_SLOT relocs when relocating conflicts.
(elf_machine_runtime_setup): Reinitialize .plt for prelinked
libraries where prelinking info cannot be used.
* sysdeps/sh/bits/link.h: New file.
* sysdeps/sh/dl-machine.h (elf_machine_runtime_setup): Save original
content of .got[1].
(elf_machine_lazy_rel): Reinitialize R_SH_JMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
* sysdeps/s390/s390-32/bits/link.h: New file.
* sysdeps/s390/s390-32/dl-machine.h (elf_machine_runtime_setup):
Save original content of .got[1].
(elf_machine_lazy_rel): Reinitialize R_390_JMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
* sysdeps/s390/s390-64/bits/link.h: New file.
* sysdeps/s390/s390-64/dl-machine.h (elf_machine_runtime_setup):
Save original content of .got[1].
(elf_machine_lazy_rel): Reinitialize R_390_JMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
* sysdeps/x86_64/bits/link.h: New file.
* sysdeps/x86_64/dl-machine.h (elf_machine_runtime_setup):
Save original content of .got[1].
(elf_machine_lazy_rel): Reinitialize R_X86_64_JMP_SLOT address instead
of adjusting it if prelinked and prelinking cannot be used.
