When -z separate-code, which is enabled by default for Linux/x86, is
used to create executable, ld won't place any data in the code-only
PT_LOAD segment. If there are no data sections placed before the
code-only PT_LOAD segment, the program headers won't be mapped into
any PT_LOAD segment. When the executable tries to access it (based
on the program header address passed in AT_PHDR), it will lead to
segfault. This patch inserts a GNU_PROPERTY_X86_ISA_1_USED note if
there may be no data sections before the text section so that the
first PT_LOAD segment won't be code-only and will contain the program
header.
Testcases are adjusted to either pass "-z noseparate-code" to ld or
discard the .note.gnu.property section. A Linux/x86 run-time test is
added.
bfd/
PR ld/23428
* elfxx-x86.c (_bfd_x86_elf_link_setup_gnu_properties): If the
separate code program header is needed, make sure that the first
read-only PT_LOAD segment has no code by adding a
GNU_PROPERTY_X86_ISA_1_USED note.
ld/
PR ld/23428
* testsuite/ld-elf/linux-x86.S: New file.
* testsuite/ld-elf/linux-x86.exp: Likewise.
* testsuite/ld-elf/pr23428.c: Likewise.
* testsuite/ld-elf/sec64k.exp: Pass "-z noseparate-code" to ld
for Linux/x86 targets.
* testsuite/ld-i386/abs-iamcu.d: Likewise.
* testsuite/ld-i386/abs.d: Likewise.
* testsuite/ld-i386/pr12718.d: Likewise.
* testsuite/ld-i386/pr12921.d: Likewise.
* testsuite/ld-x86-64/abs-k1om.d: Likewise.
* testsuite/ld-x86-64/abs-l1om.d: Likewise.
* testsuite/ld-x86-64/abs.d: Likewise.
* testsuite/ld-x86-64/pr12718.d: Likewise.
* testsuite/ld-x86-64/pr12921.d: Likewise.
* testsuite/ld-linkonce/zeroeh.ld: Discard .note.gnu.property
section.
* testsuite/ld-scripts/print-memory-usage.t: Likewise.
* testsuite/ld-scripts/size-2.t: Likewise.
* testsuite/lib/ld-lib.exp (run_ld_link_exec_tests): Use ld
to create executable if language is "asm".
There is no need to generate x86 ISA properties with empty bits in
linker output.
bfd/
PR ld/23372
* elfxx-x86.c (_bfd_x86_elf_merge_gnu_properties): Remove x86
ISA properties with empty bits.
ld/
PR ld/23372
* testsuite/ld-i386/i386.exp: Run pr23372a and pr23372b.
* testsuite/ld-i386/pr23372a.d: New file.
* testsuite/ld-i386/pr23372a.s: Likewise.
* testsuite/ld-i386/pr23372b.d: Likewise.
* testsuite/ld-i386/pr23372b.s: Likewise.
* testsuite/ld-i386/pr23372c.s: Likewise.
* testsuite/ld-x86-64/pr23372a-x32.d: Likewise.
* testsuite/ld-x86-64/pr23372a.d: Likewise.
* testsuite/ld-x86-64/pr23372a.s: Likewise.
* testsuite/ld-x86-64/pr23372b-x32.d: Likewise.
* testsuite/ld-x86-64/pr23372b.d: Likewise.
* testsuite/ld-x86-64/pr23372b.s: Likewise.
* testsuite/ld-x86-64/pr23372c.s: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run pr23372a, pr23372a-x32,
pr23372b and pr23372b-x32.
bfd_hide_sym_by_version can't be used to check if a versioned symbol is
hidden. This patch adds _bfd_elf_link_hide_sym_by_version to support
both versioned and unversioned symbols by extracting versioned symbol
check from _bfd_elf_link_assign_sym_version.
bfd/
PR ld/23194
* elf-bfd.h (_bfd_elf_link_hide_sym_by_version): New.
* elflink.c (_bfd_elf_link_hide_versioned_symbol): New function.
Extracted from _bfd_elf_link_assign_sym_version.
(_bfd_elf_link_hide_sym_by_version): New function.
(_bfd_elf_link_assign_sym_version): Use
_bfd_elf_link_hide_versioned_symbol.
* elfxx-x86.c (_bfd_x86_elf_link_symbol_references_local): Call
_bfd_elf_link_hide_sym_by_version instead of
bfd_hide_sym_by_version. Don't check unversioned symbol.
ld/
PR ld/23194
* testsuite/ld-i386/pr23194.d: Expect only R_386_GLOB_DAT
against foobar.
* testsuite/ld-i386/pr23194.map: Add foobar.
* testsuite/ld-x86-64/pr23194.map: Likewise.
* testsuite/ld-i386/pr23194.s: Add a common foobar symbol.
* testsuite/ld-x86-64/pr23194.s: Likewise.
* testsuite/ld-x86-64/pr23194.d: Expect only R_X86_64_GLOB_DAT
against foobar.
bfd_hide_sym_by_version can't be used to check if a versioned symbol is
hidden. It has to be synced with _bfd_elf_link_assign_sym_version to
get the correct answer.
bfd/
PR ld/23194
* elfxx-x86.c (_bfd_x86_elf_link_symbol_references_local): Don't
set eh->local_ref to 1 if a symbol is versioned and there is a
version script.
ld/
PR ld/23194
* testsuite/ld-i386/i386.exp: Run pr23194.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr23194.d: New file.
* testsuite/ld-i386/pr23194.map: Likewise.
* testsuite/ld-i386/pr23194.s: Likewise.
* testsuite/ld-x86-64/pr23194.d: Likewise.
* testsuite/ld-x86-64/pr23194.map: Likewise.
* testsuite/ld-x86-64/pr23194.s: Likewise.
Since the pr23189 test isn't Linux specific, run it for all targets.
* testsuite/ld-i386/i386.exp: Run pr23189 for all targets.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
Since symbols created by HIDDEN and PROVIDE_HIDDEN assignments in
linker script may be marked as defined, but not hidden, we can't
set eh->local_ref to 1 in _bfd_x86_elf_link_symbol_references_local.
Also R_386_GOT32X should be handled as just like R_386_GOT32 when
relocating a section. The input R_386_GOT32X relocations, which
can be relaxed, should have been converted to R_386_PC32, R_386_32
or R_386_GOTOFF.
bfd/
PR ld/23189
* elf32-i386.c (elf_i386_relocate_section): Handle R_386_GOT32X
like R_386_GOT32.
* elfxx-x86.c (_bfd_x86_elf_link_symbol_references_local): Don't
set eh->local_ref to 1 for linker defined symbols.
ld/
PR ld/23189
* testsuite/ld-i386/i386.exp: Run pr23189.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr23189.d: New file.
* testsuite/ld-i386/pr23189.s: Likewise.
* testsuite/ld-i386/pr23189.t: Likewise.
* testsuite/ld-x86-64/pr23189.d: Likewise.
* testsuite/ld-x86-64/pr23189.s: Likewise.
* testsuite/ld-x86-64/pr23189.t: Likewise.
When resolving a relocation against IFUNC symbol in a SHT_NOTE section
without SHF_ALLOC, we treat it as relocation against FUNC symbol since
it needs the address of IFUNC symbol, not the address returned by IFUNC
function.
bfd/
PR ld/22929
* elf32-i386.c (elf_i386_relocate_section): Treat relocation
against IFUNC symbol in SHT_NOTE section without SHF_ALLOC as
relocation against FUNC symbol.
* elf64-x86-64.c (elf_x86_64_relocate_section): Likewise.
ld/
PR ld/22929
* testsuite/ld-i386/i386.exp: Run PR ld/22929 test.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr22929.d: New file.
* testsuite/ld-i386/pr22929.s: Likewise.
* testsuite/ld-x86-64/pr22929.d: Likewise.
* testsuite/ld-x86-64/pr22929.s: Likewise.
Since PLT in PDE and PC-relative PLT in PIE can be used as function
address, there is no need for dynamic PC-relative relocation against
a dynamic function definition in PIE. Linker should resolve PC-relative
reference to its PLT address.
NB: i386 has non-PIC PLT and PIC PLT. Only non-PIC PLT in PDE can
be used as function address. PIC PLT in PIE can't be used as
function address.
bfd/
PR ld/22842
* elf32-i386.c (elf_i386_check_relocs): Pass FALSE for non
PC-relative PLT to NEED_DYNAMIC_RELOCATION_P.
* elf64-x86-64.c (elf_x86_64_check_relocs): Create PLT for
R_X86_64_PC32 reloc against dynamic function in data section.
Pass TRUE for PC-relative PLT to NEED_DYNAMIC_RELOCATION_P.
(elf_x86_64_relocate_section): Use PLT for R_X86_64_PC32 reloc
against dynamic function in data section.
* elfxx-x86.c (elf_x86_allocate_dynrelocs): Use PLT in PIE as
function address only if pcrel_plt is true.
(_bfd_x86_elf_link_hash_table_create): Set pcrel_plt.
* elfxx-x86.h (NEED_DYNAMIC_RELOCATION_P): Add PCREL_PLT for
PC-relative PLT. If PLT is PC-relative, don't generate dynamic
PC-relative relocation against a function definition in data
secton in PIE. Remove the obsolete comments.
(elf_x86_link_hash_table): Add pcrel_plt.
ld/
PR ld/22842
* testsuite/ld-i386/i386.exp: Run PR ld/22842 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr22842a.c: New file.
* testsuite/ld-i386/pr22842b.S: Likewise.
* testsuite/ld-x86-64/pr22842a.c: Likewise.
* testsuite/ld-x86-64/pr22842a.rd: Likewise.
* testsuite/ld-x86-64/pr22842b.S: Likewise.
* testsuite/ld-x86-64/pr22842b.rd: Likewise.
Since _GLOBAL_OFFSET_TABLE_ may be referenced implicitly on x86,
checking ref_regular_nonweak leaves the unused _GLOBAL_OFFSET_TABLE_
in output. This patch checks explicit GOT references instead.
ld-i386/discarded1.s and ld-x86-64/discarded1.s are updated to avoid
linker optimization which removes GOT references.
bfd/
PR ld/22782
* elf32-i386.c (elf_i386_check_relocs): Set got_referenced if
_GLOBAL_OFFSET_TABLE_ is referenced or GOT is needed to resolve
undefined weak symbol to 0.
* elf64-x86-64.c (elf_x86_64_check_relocs): Set got_referenced
if _GLOBAL_OFFSET_TABLE_ is referenced.
* elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Check
got_referenced instead of ref_regular_nonweak. Remove the
unused _GLOBAL_OFFSET_TABLE_ from symbol table.
* elfxx-x86.h (elf_x86_link_hash_table): Add got_referenced.
ld/
PR ld/22782
* testsuite/ld-i386/discarded1.s: Replace mov with div.
* testsuite/ld-x86-64/discarded1.s: Likewise.
* testsuite/ld-i386/i386.exp: Run pr22782.
* testsuite/ld-i386/load1-nacl.d: Updated for removing
_GLOBAL_OFFSET_TABLE_ from output.
* testsuite/ld-i386/load1.d: Likewise.
* testsuite/ld-x86-64/load1a-nacl.d: Likewise.
* testsuite/ld-x86-64/load1a.d: Likewise.
* testsuite/ld-x86-64/load1b-nacl.d: Likewise.
* testsuite/ld-x86-64/load1b.d: Likewise.
* testsuite/ld-i386/pr22782.d: New file.
* testsuite/ld-i386/pr22782.s: Likewise.
* testsuite/ld-x86-64/pr22782.s: Likewise.
* testsuite/ld-x86-64/pr22782a.d: Likewise.
* testsuite/ld-x86-64/pr22782b.d: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run pr22782a and pr22782b.
bfd/
PR ld/22135
* elf32-i386.c (elf_i386_convert_load_reloc): Add an argument
to indicate if conversion is performed.
(elf_i386_check_relocs): Cache section contents and relocations
if conversion is performed.
* elf64-x86-64.c (elf_x86_64_check_relocs): Cache section
contents and relocations if conversion is performed.
ld/
PR ld/22135
* testsuite/ld-i386/i386.exp: Run pr22135.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr22135.d: New file.
* testsuite/ld-i386/pr22135.s: Likewise.
* testsuite/ld-x86-64/pr22135.d: Likewise.
* testsuite/ld-x86-64/pr22135.s: Likewise.
After _bfd_i386_elf_convert_load and _bfd_x86_64_elf_convert_load are
removed, elf_i386_convert_load_reloc and elf_x86_64_convert_load_reloc
see __ehdr_start as an undefined symbol when they are called from
check_relocs to convert GOT relocations against local symbols. But
__ehdr_start will be defined as a hidden symbol by linker at the later
stage if it is referenced. This patch marks __ehdr_start as a defined
local symbol at the start of check_relocs if it is referenced and not
defined.
bfd/
PR ld/22115
* elf32-i386.c (elf_i386_convert_load_reloc): Check linker_def.
Don't use UNDEFINED_WEAK_RESOLVED_TO_ZERO.
* elf64-x86-64.c (elf_x86_64_convert_load_reloc): Check
linker_def. Don't use UNDEFINED_WEAK_RESOLVED_TO_ZERO.
* elfxx-x86.c (_bfd_x86_elf_link_check_relocs): Set local_ref
and linker_def on __ehdr_start if it is referenced and not
defined.
(_bfd_x86_elf_link_symbol_references_local): Also set local_ref
and return TRUE when building executable, if a symbol has
non-GOT/non-PLT relocations in text section or there is no
dynamic linker.
* elfxx-x86.h (elf_x86_link_hash_entry): Add linker_def.
ld/
PR ld/22115
* ld-i386/i386.exp: Run PR ld/22115 tests,
* ld/testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr22115-1.s: New file.
* testsuite/ld-i386/pr22115-1a.d: Likewise.
* testsuite/ld-i386/pr22115-1b.d: Likewise.
* testsuite/ld-i386/pr22115-1c.d: Likewise.
* testsuite/ld-i386/pr22115-1d.d: Likewise.
* testsuite/ld-x86-64/pr22115-1.s: Likewise.
* testsuite/ld-x86-64/pr22115-1a-x32.d: Likewise.
* testsuite/ld-x86-64/pr22115-1a.d: Likewise.
* testsuite/ld-x86-64/pr22115-1b-x32.d: Likewise.
* testsuite/ld-x86-64/pr22115-1b.d: Likewise.
* testsuite/ld-x86-64/pr22115-1c-x32.d: Likewise.
* testsuite/ld-x86-64/pr22115-1c.d: Likewise.
* testsuite/ld-x86-64/pr22115-1d-x32.d: Likewise.
* testsuite/ld-x86-64/pr22115-1d.d: Likewise.
We shpouldn't generate copy relocation to resolve reference to protected
data symbol defined in shared object with the NO_COPY_ON_PROTECTED
property. This patch adds a bit to elf_obj_tdata as well as
elf_i386_link_hash_entry and elf_x86_64_link_hash_entry to track the bfd
with the NO_COPY_ON_PROTECTED property as well as protected symbol
defined in shared object. extern_protected_data is set to FALSE if any
input relocatable file contains the NO_COPY_ON_PROTECTED property.
bfd/
PR ld/21997
* elf-bfd.h (elf_obj_tdata): Use ENUM_BITFIELD on object_id,
dyn_lib_class and has_gnu_symbols. Change bad_symtab to bitfield.
Add a has_no_copy_on_protected bitfield.
(elf_has_no_copy_on_protected): New.
* elf-properties.c (_bfd_elf_parse_gnu_properties): Set
elf_has_no_copy_on_protected for GNU_PROPERTY_NO_COPY_ON_PROTECTED.
(elf_merge_gnu_property_list): Likewise.
(_bfd_elf_link_setup_gnu_properties): Set extern_protected_data
to FALSE for elf_has_no_copy_on_protected.
* elf32-i386.c (SYMBOL_NO_COPYRELOC): New.
(elf_i386_link_hash_entry): Add def_protected.
(elf_i386_adjust_dynamic_symbol): Also check SYMBOL_NO_COPYRELOC
when checking info->nocopyreloc.
(elf_i386_link_setup_gnu_properties): Don't set
extern_protected_data here.
(elf_i386_merge_symbol_attribute): New function.
(elf_backend_merge_symbol_attribute): New.
* elf64-x86-64.c (SYMBOL_NO_COPYRELOC): New.
(elf_x86_64_link_hash_entry): Add def_protected.
(elf_x86_64_need_pic): Report protected symbol for def_protected.
(elf_x86_64_adjust_dynamic_symbol): Also check SYMBOL_NO_COPYRELOC
when checking info->nocopyreloc.
(elf_x86_64_relocate_section): Also check for R_X86_64_PC32
relocation run-time overflow and unresolvable R_X86_64_32S
relocation against protected data symbol defined in shared object
with GNU_PROPERTY_NO_COPY_ON_PROTECTED.
(elf_x86_64_link_setup_gnu_properties): Don't set
extern_protected_data here.
(elf_x86_64_merge_symbol_attribute): New function.
(elf_backend_merge_symbol_attribute): New.
ld/
PR ld/21997
* testsuite/ld-i386/i386.exp: Run PR ld/21997 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr21997-1a.S: New file.
* testsuite/ld-i386/pr21997-1b.c: Likewise.
* testsuite/ld-i386/pr21997-1c.S: Likewise.
* testsuite/ld-x86-64/pr21997-1a.S: Likewise.
* testsuite/ld-x86-64/pr21997-1a.err: Likewise.
* testsuite/ld-x86-64/pr21997-1b.c: Likewise.
* testsuite/ld-x86-64/pr21997-1b.err: Likewise.
* testsuite/ld-x86-64/pr21997-1c.c: Likewise.
Replace regexp with string match to workaround dejagnu 1.4.4 which
complains:
ERROR: bad switch "-fPIE": must be -all, -about, -indices, -inline, -expanded, -line, -linestop, -lineanchor, -nocase, -start, or --
* testsuite/ld-i386/i386.exp (undefined_weak): Replace regexp
with string match.
* testsuite/ld-x86-64/x86-64.exp (undefined_weak): Likewise.
On x86-64, when -z nocopyreloc is used to build executable, relocations
may overflow at run-time or may not be resolved without PIC. This patch
checks these conditions and issues an error with suggestion for -fPIC.
bfd/
PR ld/22001
* elf64-x86-64.c (elf_x86_64_relocate_section): Check for
R_X86_64_PC32 relocation run-time overflow and unresolvable
R_X86_64_32S relocation with -z nocopyreloc.
ld/
PR ld/22001
* testsuite/ld-i386/i386.exp: Run -z nocopyreloc tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* ld/testsuite/ld-i386/pr22001-1a.c: New file.
* ld/testsuite/ld-i386/pr22001-1b.c: Likewise.
* ld/testsuite/ld-i386/pr22001-1c.S: Likewise.
* ld/testsuite/ld-x86-64/pr22001-1a.c: Likewise.
* ld/testsuite/ld-x86-64/pr22001-1a.err: Likewise.
* ld/testsuite/ld-x86-64/pr22001-1b.c: Likewise.
* ld/testsuite/ld-x86-64/pr22001-1b.err: Likewise.
* ld/testsuite/ld-x86-64/pr22001-1c.c: Likewise.
When GNU_PROPERTY_NO_COPY_ON_PROTECTED is set, it indicates that there
are no copy relocations against protected data symbols. When linker
sees GNU_PROPERTY_NO_COPY_ON_PROTECTED on any input relocatable file,
it sets extern_protected_data to FALSE.
bfd/
* elf32-i386.c (elf_i386_link_setup_gnu_properties): Set
extern_protected_data to FALSE if GNU_PROPERTY_NO_COPY_ON_PROTECTED
is set on any input relocatable file.
* elf64-x86-64.c (elf_x86_64_link_setup_gnu_properties): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Run protected7.
* testsuite/ld-i386/protected7.d: New file.
* testsuite/ld-i386/protected7.s: Likewise.
* testsuite/ld-x86-64/protected8.d: Likewise.
* testsuite/ld-x86-64/protected8.s: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Run protected8.
OUTPUT_FORMAT in linker script of PR ld/21884 tests is needed to trigger
PR ld/21884. Restore linker scripts and add nacl versions of the same
tests.
* testsuite/ld-i386/i386.exp: Run pr21884-nacl.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr21884.d: Don't run on nacl targets.
* testsuite/ld-x86-64/pr21884.d: Likewise.
* testsuite/ld-i386/pr21884.t: Revert the last change.
* testsuite/ld-x86-64/pr21884.t: Likewise.
* testsuite/ld-i386/pr21884-nacl.d: New file.
* testsuite/ld-i386/pr21884-nacl.t: Likewise.
* testsuite/ld-x86-64/pr21884-nacl.d: Likewise.
* testsuite/ld-x86-64/pr21884-nacl.t: Likewise.
OUTPUT_FORMAT in the script results in "./ld-new: target elf32-i386
not found" and similarly for the x86_64 test.
* testsuite/ld-i386/pr21884.t: Remove unneeded format, arch and entry.
* testsuite/ld-x86-64/pr21884.t: Likewise.
Require GCC 5 or above for 3 x86 tests which fail with GCC 4.9.3.
PR ld/21924
* testsuite/ld-i386/i386.exp: Require GCC 5 or above for
"weakundef1 with PIE" test.
* testsuite/ld-x86-64/tls.exp: Require GCC 5 or above for
"tlsdesc1" and "tlsdesc1 with PIE" tests.
To support IBT in Intel Control-flow Enforcement Technology (CET)
instructions:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf
#define GNU_PROPERTY_X86_FEATURE_1_AND 0xc0000002
#define GNU_PROPERTY_X86_FEATURE_1_IBT (1U << 0)
are added to GNU program properties to indicate that all executable
sections are compatible with IBT when ENDBR instruction starts each
valid target where an indirect branch instruction can land.
GNU_PROPERTY_X86_FEATURE_1_IBT is set on output only if it is set on
all relocatable inputs.
The followings changes are made to the Procedure Linkage Table (PLT):
1. For 64-bit x86-64, PLT is changed to
PLT0: push GOT[1]
bnd jmp *GOT[2]
nop
...
PLTn: endbr64
push namen_reloc_index
bnd jmp PLT0
together with the second PLT section:
PLTn: endbr64
bnd jmp *GOT[namen_index]
nop
BND prefix is also added so that IBT-enabled PLT is compatible with MPX.
2. For 32-bit x86-64 (x32) and i386, PLT is changed to
PLT0: push GOT[1]
jmp *GOT[2]
nop
...
PLTn: endbr64 # endbr32 for i386.
push namen_reloc_index
jmp PLT0
together with the second PLT section:
PLTn: endbr64 # endbr32 for i386.
jmp *GOT[namen_index]
nop
BND prefix isn't used since MPX isn't supported on x32 and BND registers
aren't used in parameter passing on i386.
GOT is an array of addresses. Initially, GOT[namen_index] is filled
with the address of the ENDBR instruction of the corresponding entry
in the first PLT section. The function, namen, is called via the
ENDBR instruction in the second PLT entry. GOT[namen_index] is updated
to the actual address of the function, namen, at run-time.
2 linker command line options are added:
1. -z ibtplt: Generate IBT-enabled PLT.
2. -z ibt: Generate GNU_PROPERTY_X86_FEATURE_1_IBT in GNU program
properties as well as IBT-enabled PLT.
bfd/
* elf32-i386.c (elf_i386_lazy_ibt_plt0_entry): New.
(elf_i386_lazy_ibt_plt_entry): Likewise.
(elf_i386_pic_lazy_ibt_plt0_entry): Likewise.
(elf_i386_non_lazy_ibt_plt_entry): Likewise.
(elf_i386_pic_non_lazy_ibt_plt_entry): Likewise.
(elf_i386_eh_frame_lazy_ibt_plt): Likewise.
(elf_i386_lazy_plt_layout): Likewise.
(elf_i386_non_lazy_plt_layout): Likewise.
(elf_i386_link_hash_entry): Add plt_second.
(elf_i386_link_hash_table): Add plt_second and
plt_second_eh_frame.
(elf_i386_allocate_dynrelocs): Use the second PLT if needed.
(elf_i386_size_dynamic_sections): Use .plt.got unwind info for
the second PLT. Check the second PLT.
(elf_i386_relocate_section): Use the second PLT to resolve
PLT reference if needed.
(elf_i386_finish_dynamic_symbol): Fill and use the second PLT if
needed.
(elf_i386_finish_dynamic_sections): Set sh_entsize on the
second PLT. Generate unwind info for the second PLT.
(elf_i386_plt_type): Add plt_second.
(elf_i386_get_synthetic_symtab): Support the second PLT.
(elf_i386_parse_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND.
(elf_i386_merge_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND. If info->ibt is set, turn
on GNU_PROPERTY_X86_FEATURE_1_IBT
(elf_i386_link_setup_gnu_properties): If info->ibt is set,
turn on GNU_PROPERTY_X86_FEATURE_1_IBT. Use IBT-enabled PLT
for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
is set on all relocatable inputs.
* elf64-x86-64.c (elf_x86_64_lazy_ibt_plt_entry): New.
(elf_x32_lazy_ibt_plt_entry): Likewise.
(elf_x86_64_non_lazy_ibt_plt_entry): Likewise.
(elf_x32_non_lazy_ibt_plt_entry): Likewise.
(elf_x86_64_eh_frame_lazy_ibt_plt): Likewise.
(elf_x32_eh_frame_lazy_ibt_plt): Likewise.
(elf_x86_64_lazy_ibt_plt): Likewise.
(elf_x32_lazy_ibt_plt): Likewise.
(elf_x86_64_non_lazy_ibt_plt): Likewise.
(elf_x32_non_lazy_ibt_plt): Likewise.
(elf_x86_64_get_synthetic_symtab): Support the second PLT.
(elf_x86_64_parse_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND.
(elf_x86_64_merge_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND. If info->ibt is set, turn
on GNU_PROPERTY_X86_FEATURE_1_IBT
(elf_x86_64_link_setup_gnu_properties): If info->ibt is set,
turn on GNU_PROPERTY_X86_FEATURE_1_IBT. Use IBT-enabled PLT
for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
is set on all relocatable inputs.
binutils/
* readelf.c (decode_x86_feature): New.
(print_gnu_property_note): Call decode_x86_feature on
GNU_PROPERTY_X86_FEATURE_1_AND.
* testsuite/binutils-all/i386/empty.d: New file.
* testsuite/binutils-all/i386/empty.s: Likewise.
* testsuite/binutils-all/i386/ibt.d: Likewise.
* testsuite/binutils-all/i386/ibt.s: Likewise.
* testsuite/binutils-all/x86-64/empty-x32.d: Likewise.
* testsuite/binutils-all/x86-64/empty.d: Likewise.
* testsuite/binutils-all/x86-64/empty.s: Likewise.
* testsuite/binutils-all/x86-64/ibt-x32.d: Likewise.
* testsuite/binutils-all/x86-64/ibt.d: Likewise.
* testsuite/binutils-all/x86-64/ibt.s: Likewise.
include/
* bfdlink.h (bfd_link_info): Add ibtplt and ibt.
* elf/common.h (GNU_PROPERTY_X86_FEATURE_1_AND): New.
(GNU_PROPERTY_X86_FEATURE_1_IBT): Likewise.
ld/
* Makefile.am (ELF_X86_DEPS): Add $(srcdir)/emulparams/cet.sh.
* Makefile.in: Regenerated.
* NEWS: Mention GNU_PROPERTY_X86_FEATURE_1_IBT, -z ibtplt
and -z ibt.
* emulparams/cet.sh: New file.
* testsuite/ld-i386/ibt-plt-1.d: Likewise.
* testsuite/ld-i386/ibt-plt-1.s: Likewise.
* testsuite/ld-i386/ibt-plt-2.s: Likewise.
* testsuite/ld-i386/ibt-plt-2a.d: Likewise.
* testsuite/ld-i386/ibt-plt-2b.d: Likewise.
* testsuite/ld-i386/ibt-plt-2c.d: Likewise.
* testsuite/ld-i386/ibt-plt-2d.d: Likewise.
* testsuite/ld-i386/ibt-plt-3.s: Likewise.
* testsuite/ld-i386/ibt-plt-3a.d: Likewise.
* testsuite/ld-i386/ibt-plt-3b.d: Likewise.
* testsuite/ld-i386/ibt-plt-3c.d: Likewise.
* testsuite/ld-i386/ibt-plt-3d.d: Likewise.
* testsuite/ld-i386/plt-main-ibt.dd: Likewise.
* testsuite/ld-i386/plt-pie-ibt.dd: Likewise.
* testsuite/ld-i386/property-x86-empty.s: Likewise.
* testsuite/ld-i386/property-x86-ibt.s: Likewise.
* testsuite/ld-i386/property-x86-ibt1a.d: Likewise.
* testsuite/ld-i386/property-x86-ibt1b.d: Likewise.
* testsuite/ld-i386/property-x86-ibt2.d: Likewise.
* testsuite/ld-i386/property-x86-ibt3a.d: Likewise.
* testsuite/ld-i386/property-x86-ibt3b.d: Likewise.
* testsuite/ld-i386/property-x86-ibt4.d: Likewise.
* testsuite/ld-i386/property-x86-ibt5.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-2.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-2a-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2a.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2b-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2b.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2d.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-3a-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3a.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3b-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3b.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d.d: Likewise.
* testsuite/ld-x86-64/plt-main-ibt-now.rd: Likewise.
* testsuite/ld-x86-64/plt-main-ibt-x32.dd: Likewise.
* testsuite/ld-x86-64/plt-main-ibt.dd: Likewise.
* testsuite/ld-x86-64/property-x86-empty.s: Likewise.
* testsuite/ld-x86-64/property-x86-ibt.s: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1a-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1a.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1b-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1b.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt2-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt2.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3a-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3a.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3b-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3b.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt4-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt4.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt5-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt5.d: Likewise.
* emulparams/elf32_x86_64.sh: Source emulparams/cet.sh.
(TINY_READONLY_SECTION): Add .plt.sec.
* emulparams/elf_i386.sh: Likewise.
* emulparams/elf_x86_64.sh: Source emulparams/cet.sh.
* ld.texinfo: Document -z ibtplt and -z ibt.
* testsuite/ld-i386/i386.exp: Run IBT and IBT PLT tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-x86-64/pr21481b.S (check): Updated for x32.
Since the BFD section count may not be cleared for shared objects during
linking, we should check the DYNAMIC bit for input shared objects.
bfd/
PR ld/21626
* elf-properties.c (_bfd_elf_link_setup_gnu_properties): Check
the DYNAMIC bit instead of bfd_count_sections.
ld/
PR ld/21626
* testsuite/ld-i386/i386.exp: Run ld/21626 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
Since it is incorrect to convert
bnd call *foo@GOTPCREL(%rip)
to
bnd nop
call foo
this patch removes the "-z prefix-nop" option from x86 linker.
* emulparams/call_nop.sh: Remove -z prefix-nop.
* ld.texinfo: Likewise.
* testsuite/ld-i386/call3c.d: Check for linker error.
* testsuite/ld-x86-64/call1c.d: Likewise.
Verify that debug section is removed by garbage collection when there
is a .note.gnu.property section.
* testsuite/ld-i386/i386.exp: Run property-x86-4a and
property-x86-4b.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/property-x86-4a.d: New file.
* testsuite/ld-i386/property-x86-4a.s: Likewise.
* testsuite/ld-i386/property-x86-4b.d: Likewise.
* testsuite/ld-i386/property-x86-4b.s: Likewise.
* testsuite/ld-x86-64/property-x86-4a.d: Likewise.
* testsuite/ld-x86-64/property-x86-4a.s: Likewise.
* testsuite/ld-x86-64/property-x86-4b.d: Likewise.
* testsuite/ld-x86-64/property-x86-4b.s: Likewise.
If there are more than GNU property note in an input, we should merge
X86_ISA_1_USED and X86_ISA_1_NEEDED properties.
bfd/
* elf32-i386.c (elf_i386_parse_gnu_properties): Merge
GNU_PROPERTY_X86_ISA_1_USED and GNU_PROPERTY_X86_ISA_1_NEEDED
properties.
* elf64-x86-64.c (elf_x86_64_parse_gnu_properties): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Run property-x86-3.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/property-x86-3.d: New file.
* testsuite/ld-i386/property-x86-3.s: Likewise.
* testsuite/ld-x86-64/property-x86-3.d: Likewise.
* testsuite/ld-x86-64/property-x86-3.s: Likewise.
This patch partially reverses:
commit 25070364b0
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Sat May 16 07:00:21 2015 -0700
Don't generate PLT relocations for now binding
to support LD_AUDIT and LD_PROFILE with -z now. If there is an existing
GOT relocation, it is still used to avoid PLT relocation against the same
function symbol.
bfd/
* elf32-i386.c (elf_i386_allocate_dynrelocs): Partially revert
commit 25070364b0.
* elf64-x86-64.c (elf_x86_64_allocate_dynrelocs): Likewse.
ld/
* testsuite/ld-i386/plt-pic2.dd: Updated.
* testsuite/ld-i386/plt2.dd: Likewise.
* testsuite/ld-i386/plt2.rd: Likewise.
* testsuite/ld-i386/pr17689now.rd: Likewise.
* testsuite/ld-ifunc/ifunc-16-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-16-x86-64-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-i386-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-x86-64-now.d: Likewise.
* testsuite/ld-x86-64/bnd-branch-1-now.d: Likewise.
* testsuite/ld-x86-64/bnd-ifunc-2-now.d: Likewise.
* testsuite/ld-x86-64/bnd-plt-1-now.d: Likewise.
* testsuite/ld-x86-64/plt2.dd: Likewise.
* testsuite/ld-x86-64/plt2.rd: Likewise.
* testsuite/ld-x86-64/pr17689now.rd: Likewise.
* testsuite/ld-x86-64/pr21038b-now.d: Likewise.
* testsuite/ld-x86-64/pr21038c-now.d: Likewise.
On i386, the procedure linkage table (PLT) is used to
1. Call external function.
2. Call internal IFUNC function. The best implementation is selected
for the target processor at run-time.
3. Act as the canonical function address.
4. Support LD_AUDIT to audit external function calls.
5. Support LD_PROFILE to profile external function calls.
PLT looks like:
PLT0: push GOT[1]
jmp *GOT[2]
nop
PLT1: jmp *GOT[name1_index]
push name1_reloc_index
jmp PLT0
GOT is an array of addresses. Initially the GOT entry of name1 is
filled with the address of the "push name1_reloc_index" instruction.
The function, name1, is called via "jmp *GOT[name1]" in the PLT entry.
Even when lazy binding is disabled by "-z now", the PLT0 entry may
still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
canonical function address.
1. With lazy binding, when the external function, name1, is called the
first time, dynamic linker is called via PLT0 to update GOT[name1_index]
with the actual address of name1 and transfers control to name1
afterwards.
2. PLT is also used to call a local IFUNC function, name1, run-time
loader updates GOT[name1_index] when loading the module.
This patch
1. Remove PLT layout configurations from i386 backend_data.
2. Add generic, lay and non-lazy PLT layout configurations to i386
link_hash_table. Generic PLT layout includes the PLT entry templates,
information how to update the first instruction in PLT and PLT eh_frame
informaton, which are initialized in i386 setup_gnu_properties, based
on PIC and target selection. PLT section alignment is also set to PLT
entry size for non-NaCl/VxWorks target.
3. Remove elf_i386_create_dynamic_sections. create_dynamic_sections
isn't always called, but GOT relocations need GOT relocations. Instead,
create all i386 specific dynamic sections in i386 setup_gnu_properties,
which initializes elf.dynobj, so that i386 check_relocs can be simplified.
4. Rewrite elf_i386_get_synthetic_symtab to check PLT sections against
all dynamic relocations to support both lazy and non-lazy PLTs.
bfd/
* elf32-i386.c (PLT_ENTRY_SIZE): Renamed to ...
(LAZY_PLT_ENTRY_SIZE): This.
(NON_LAZY_PLT_ENTRY_SIZE): New.
(elf_i386_plt0_entry): Renamed to ...
(elf_i386_lazy_plt0_entry): This.
(elf_i386_plt_entry): Renamed to ...
(elf_i386_lazy_plt_entry): This.
(elf_i386_pic_plt0_entry): Renamed to ...
(elf_i386_pic_lazy_plt0_entry): This.
(elf_i386_pic_plt_entry): Renamed to ...
(elf_i386_pic_lazy_plt_entry): This.
(elf_i386_got_plt_entry): Renamed to ...
(elf_i386_non_lazy_plt_entry): This.
(elf_i386_pic_got_plt_entry): Renamed to ...
(elf_i386_pic_non_lazy_plt_entry): This.
(elf_i386_eh_frame_plt): Renamed to ...
(elf_i386_eh_frame_lazy_plt): This.
(elf_i386_eh_frame_plt_got): Renamed to ...
(elf_i386_eh_frame_non_lazy_plt): This.
(elf_i386_plt_layout): Renamed to ...
(elf_i386_lazy_plt_layout): This. Remove eh_frame_plt_got and
eh_frame_plt_got_size.
(elf_i386_non_lazy_plt_layout): New.
(elf_i386_plt_layout): Likewise.
(elf_i386_non_lazy_plt): Likewise.
(GET_PLT_ENTRY_SIZE): Removed.
(elf_i386_plt): Renamed to ...
(elf_i386_lazy_plt): This.
(elf_i386_backend_data): Remove plt. Rename is_vxworks to os.
(elf_i386_arch_bed): Updated.
(elf_i386_link_hash_table): Add plt, lazy_plt and non_lazy_plt.
(elf_i386_create_dynamic_sections): Removed.
(elf_i386_check_relocs): Don't check elf.dynobj. Don't call
_bfd_elf_create_ifunc_sections nor _bfd_elf_create_got_section.
(elf_i386_adjust_dynamic_symbol): Updated.
(elf_i386_allocate_dynrelocs): Updated. Pass 0 as PLT header
size to _bfd_elf_allocate_ifunc_dyn_relocs and don't allocate
size for PLT0 if there is no PLT0.
(elf_i386_size_dynamic_sections): Updated. Check whether GOT
output section is discarded only if GOT isn't empty.
(elf_i386_relocate_section): Updated. Properly get PLT index
if there is no PLT0.
(elf_i386_finish_dynamic_symbol): Updated. Don't fill the
second and third slots in the PLT entry if there is no PLT0.
(elf_i386_finish_dynamic_sections): Updated. Don't fill PLT0
if there is no PLT0. Set sh_entsize on the .plt.got section.
(elf_i386_nacl_plt): Forward declaration.
(elf_i386_get_plt_sym_val): Removed.
(elf_i386_get_synthetic_symtab): Rewrite to check PLT sections
against all dynamic relocations.
(elf_i386_link_setup_gnu_properties): New function.
(elf_backend_create_dynamic_sections): Updated.
(elf_backend_setup_gnu_properties): New.
(elf_i386_nacl_plt): Updated.
(elf_i386_nacl_arch_bed): Likewise.
(elf_i386_vxworks_arch_bed): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Add some -z now tests.
* testsuite/ld-i386/plt-pic2.dd: New file.
* testsuite/ld-i386/plt2.dd: Likewise.
* testsuite/ld-i386/plt2.rd: Likewise.
* testsuite/ld-i386/plt2.s: Likewise.
* testsuite/ld-ifunc/ifunc-16-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-2-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-2-local-i386-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-i386-now.d: Likewise.
* testsuite/ld-i386/pr20830.d: Update the .plt.got section
with func@plt.
* testsuite/ld-i386/tls.exp: Add -Wl,--no-as-needed to
"TLS without PLT (1)" and "TLS without PLT (3)".
* testsuite/ld-x86-64/tls.exp: Add -Wl,--no-as-needed to
to "TLS without PLT (3)".
Check if GNU2 TLS really works before running GNU2 TLS tests.
* testsuite/ld-i386/tls.exp: Run GNU2 TLS tests only if there
is working GNU2 TLS support.
* testsuite/ld-x86-64/tls.exp: Likewise.
* testsuite/lib/ld-lib.exp (check_gnu2_tls_available): New proc.
