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- /* x86 specific support for ELF
- Copyright (C) 2017-2022 Free Software Foundation, Inc.
- This file is part of BFD, the Binary File Descriptor library.
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
- MA 02110-1301, USA. */
- /* Don't generate unused section symbols. */
- #define TARGET_KEEP_UNUSED_SECTION_SYMBOLS false
- #include "sysdep.h"
- #include "bfd.h"
- #include "bfdlink.h"
- #include "libbfd.h"
- #include "elf-bfd.h"
- #include "hashtab.h"
- #include "elf-linker-x86.h"
- #include "elf/i386.h"
- #include "elf/x86-64.h"
- #define X86_64_PCREL_TYPE_P(TYPE) \
- ((TYPE) == R_X86_64_PC8 \
- || (TYPE) == R_X86_64_PC16 \
- || (TYPE) == R_X86_64_PC32 \
- || (TYPE) == R_X86_64_PC32_BND \
- || (TYPE) == R_X86_64_PC64)
- #define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
- #define X86_PCREL_TYPE_P(IS_X86_64, TYPE) \
- ((IS_X86_64) ? X86_64_PCREL_TYPE_P (TYPE) : I386_PCREL_TYPE_P (TYPE))
- #define X86_64_SIZE_TYPE_P(TYPE) \
- ((TYPE) == R_X86_64_SIZE32 || (TYPE) == R_X86_64_SIZE64)
- #define I386_SIZE_TYPE_P(TYPE) ((TYPE) == R_386_SIZE32)
- #define X86_SIZE_TYPE_P(IS_X86_64, TYPE) \
- ((IS_X86_64) ? X86_64_SIZE_TYPE_P(TYPE) : I386_SIZE_TYPE_P (TYPE))
- #define X86_64_GOT_TYPE_P(TYPE) \
- ((TYPE) == R_X86_64_GOTPCREL \
- || (TYPE) == R_X86_64_GOTPCRELX \
- || (TYPE) == R_X86_64_REX_GOTPCRELX \
- || (TYPE) == R_X86_64_GOT32 \
- || (TYPE) == R_X86_64_GOT64 \
- || (TYPE) == R_X86_64_GOTPCREL64 \
- || (TYPE) == R_X86_64_GOTPLT64)
- #define I386_GOT_TYPE_P(TYPE) \
- ((TYPE) == R_386_GOT32 || (TYPE) == R_386_GOT32X)
- #define X86_GOT_TYPE_P(IS_X86_64, TYPE) \
- ((IS_X86_64) ? X86_64_GOT_TYPE_P (TYPE) : I386_GOT_TYPE_P (TYPE))
- #define X86_64_RELATIVE_RELOC_TYPE_P(TYPE) \
- (X86_64_PCREL_TYPE_P (TYPE) \
- || (TYPE) == R_X86_64_8 \
- || (TYPE) == R_X86_64_16 \
- || (TYPE) == R_X86_64_32 \
- || (TYPE) == R_X86_64_32S \
- || (TYPE) == R_X86_64_64)
- #define I386_RELATIVE_RELOC_TYPE_P(TYPE) \
- ((TYPE) == R_386_32 || (TYPE) == R_386_PC32)
- #define X86_RELATIVE_RELOC_TYPE_P(IS_X86_64, TYPE) \
- ((IS_X86_64) \
- ? X86_64_RELATIVE_RELOC_TYPE_P (TYPE) \
- : I386_RELATIVE_RELOC_TYPE_P(TYPE))
- #define X86_64_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
- (X86_64_SIZE_TYPE_P (TYPE) \
- || X86_64_RELATIVE_RELOC_TYPE_P (TYPE))
- #define I386_NEED_DYNAMIC_RELOC_TYPE_P(TYPE) \
- (I386_SIZE_TYPE_P (TYPE) \
- || I386_RELATIVE_RELOC_TYPE_P (TYPE) \
- || (TYPE) == R_386_TLS_IE \
- || (TYPE) == R_386_TLS_LE \
- || (TYPE) == R_386_TLS_LE_32)
- #define X86_NEED_DYNAMIC_RELOC_TYPE_P(IS_X86_64, TYPE) \
- ((IS_X86_64) \
- ? X86_64_NEED_DYNAMIC_RELOC_TYPE_P (TYPE) \
- : I386_NEED_DYNAMIC_RELOC_TYPE_P (TYPE))
- #define X86_LOCAL_GOT_RELATIVE_RELOC_P(IS_X86_64, INFO, SYM) \
- (bfd_link_pic (INFO) \
- && (!(IS_X86_64) || ((SYM) != NULL && (SYM)->st_shndx != SHN_ABS)))
- #define PLT_CIE_LENGTH 20
- #define PLT_FDE_LENGTH 36
- #define PLT_FDE_START_OFFSET 4 + PLT_CIE_LENGTH + 8
- #define PLT_FDE_LEN_OFFSET 4 + PLT_CIE_LENGTH + 12
- #define I386_PCREL_TYPE_P(TYPE) ((TYPE) == R_386_PC32)
- #define X86_64_PCREL_TYPE_P(TYPE) \
- ((TYPE) == R_X86_64_PC8 \
- || (TYPE) == R_X86_64_PC16 \
- || (TYPE) == R_X86_64_PC32 \
- || (TYPE) == R_X86_64_PC32_BND \
- || (TYPE) == R_X86_64_PC64)
- #define ABI_64_P(abfd) \
- (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS64)
- /* If ELIMINATE_COPY_RELOCS is non-zero, the linker will try to avoid
- copying dynamic variables from a shared lib into an app's dynbss
- section, and instead use a dynamic relocation to point into the
- shared lib. */
- #define ELIMINATE_COPY_RELOCS 1
- #define elf_x86_hash_table(p, id) \
- (is_elf_hash_table ((p)->hash) \
- && elf_hash_table_id ((struct elf_link_hash_table *) ((p)->hash)) == (id) \
- ? ((struct elf_x86_link_hash_table *) ((p)->hash)) : NULL)
- /* Will references to this symbol always be local in this object? */
- #define SYMBOL_REFERENCES_LOCAL_P(INFO, H) \
- _bfd_x86_elf_link_symbol_references_local ((INFO), (H))
- /* TRUE if an undefined weak symbol should be resolved to 0. Local
- undefined weak symbol is always resolved to 0. Reference to an
- undefined weak symbol is resolved to 0 in executable if undefined
- weak symbol should be resolved to 0 (zero_undefweak > 0). */
- #define UNDEFINED_WEAK_RESOLVED_TO_ZERO(INFO, EH) \
- ((EH)->elf.root.type == bfd_link_hash_undefweak \
- && (SYMBOL_REFERENCES_LOCAL_P ((INFO), &(EH)->elf) \
- || (bfd_link_executable (INFO) \
- && (EH)->zero_undefweak > 0)))
- /* Should copy relocation be generated for a symbol. Don't generate
- copy relocation against a protected symbol defined in a shared
- object with GNU_PROPERTY_NO_COPY_ON_PROTECTED. */
- #define SYMBOL_NO_COPYRELOC(INFO, EH) \
- ((EH)->def_protected \
- && ((EH)->elf.root.type == bfd_link_hash_defined \
- || (EH)->elf.root.type == bfd_link_hash_defweak) \
- && elf_has_no_copy_on_protected ((EH)->elf.root.u.def.section->owner) \
- && ((EH)->elf.root.u.def.section->owner->flags & DYNAMIC) != 0 \
- && ((EH)->elf.root.u.def.section->flags & SEC_CODE) == 0)
- /* TRUE if dynamic relocation is needed. If we are creating a shared
- library, and this is a reloc against a global symbol, or a non PC
- relative reloc against a local symbol, then we need to copy the reloc
- into the shared library. However, if we are linking with -Bsymbolic,
- we do not need to copy a reloc against a global symbol which is
- defined in an object we are including in the link (i.e., DEF_REGULAR
- is set).
- If PCREL_PLT is true, don't generate dynamic relocation in PIE for
- PC-relative relocation against a dynamic function definition in data
- section when PLT address can be used.
- If on the other hand, we are creating an executable, we may need to
- keep relocations for symbols satisfied by a dynamic library if we
- manage to avoid copy relocs for the symbol.
- We also need to generate dynamic pointer relocation against
- STT_GNU_IFUNC symbol in the non-code section. */
- #define NEED_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, PCREL_PLT, H, SEC, \
- R_TYPE, POINTER_TYPE) \
- ((bfd_link_pic (INFO) \
- && (! X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
- || ((H) != NULL \
- && (! (bfd_link_pie (INFO) \
- || SYMBOLIC_BIND ((INFO), (H))) \
- || (H)->root.type == bfd_link_hash_defweak \
- || (!(bfd_link_pie (INFO) \
- && (PCREL_PLT) \
- && (H)->plt.refcount > 0 \
- && ((SEC)->flags & SEC_CODE) == 0 \
- && (H)->type == STT_FUNC \
- && (H)->def_dynamic) \
- && !(H)->def_regular))))) \
- || ((H) != NULL \
- && (H)->type == STT_GNU_IFUNC \
- && (R_TYPE) == POINTER_TYPE \
- && ((SEC)->flags & SEC_CODE) == 0) \
- || (ELIMINATE_COPY_RELOCS \
- && !bfd_link_pic (INFO) \
- && (H) != NULL \
- && ((H)->root.type == bfd_link_hash_defweak \
- || !(H)->def_regular)))
- /* TRUE if dynamic relocation should be generated. Don't copy a
- pc-relative relocation into the output file if the symbol needs
- copy reloc or the symbol is undefined when building executable.
- Copy dynamic function pointer relocations. Don't generate dynamic
- relocations against resolved undefined weak symbols in PIE, except
- when PC32_RELOC is TRUE. Undefined weak symbol is bound locally
- when PIC is false. Don't generate dynamic relocations against
- non-preemptible absolute symbol. NB: rel_from_abs is set on symbols
- defined by linker scripts from "dot" (also SEGMENT_START or ORIGIN)
- outside of an output section statement, which will be converted from
- absolute to section-relative in set_sym_sections called from
- ldexp_finalize_syms after ldemul_finish. */
- #define GENERATE_DYNAMIC_RELOCATION_P(IS_X86_64, INFO, EH, R_TYPE, \
- SEC, NEED_COPY_RELOC_IN_PIE, \
- RESOLVED_TO_ZERO, PC32_RELOC) \
- ((bfd_link_pic (INFO) \
- && !(bfd_is_abs_section (SEC) \
- && ((EH) == NULL \
- || (EH)->elf.root.rel_from_abs == 0) \
- && ((EH) == NULL \
- || SYMBOL_REFERENCES_LOCAL (INFO, &(EH)->elf))) \
- && !(NEED_COPY_RELOC_IN_PIE) \
- && ((EH) == NULL \
- || ((ELF_ST_VISIBILITY ((EH)->elf.other) == STV_DEFAULT \
- && (!(RESOLVED_TO_ZERO) || PC32_RELOC)) \
- || (EH)->elf.root.type != bfd_link_hash_undefweak)) \
- && ((!X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
- && !X86_SIZE_TYPE_P (IS_X86_64, R_TYPE)) \
- || ! SYMBOL_CALLS_LOCAL ((INFO), \
- (struct elf_link_hash_entry *) (EH)))) \
- || (ELIMINATE_COPY_RELOCS \
- && !bfd_link_pic (INFO) \
- && (EH) != NULL \
- && (EH)->elf.dynindx != -1 \
- && (!(EH)->elf.non_got_ref \
- || ((EH)->elf.root.type == bfd_link_hash_undefweak \
- && !(RESOLVED_TO_ZERO))) \
- && (((EH)->elf.def_dynamic && !(EH)->elf.def_regular) \
- || (EH)->elf.root.type == bfd_link_hash_undefined)))
- /* TRUE if this input relocation should be copied to output. H->dynindx
- may be -1 if this symbol was marked to become local. */
- #define COPY_INPUT_RELOC_P(IS_X86_64, INFO, H, R_TYPE) \
- ((H) != NULL \
- && (H)->dynindx != -1 \
- && (X86_PCREL_TYPE_P (IS_X86_64, R_TYPE) \
- || !(bfd_link_executable (INFO) || SYMBOLIC_BIND ((INFO), (H))) \
- || !(H)->def_regular))
- /* TRUE if this is actually a static link, or it is a -Bsymbolic link
- and the symbol is defined locally, or the symbol was forced to be
- local because of a version file. */
- #define RESOLVED_LOCALLY_P(INFO, H, HTAB) \
- (!WILL_CALL_FINISH_DYNAMIC_SYMBOL ((HTAB)->elf.dynamic_sections_created, \
- bfd_link_pic (INFO), (H)) \
- || (bfd_link_pic (INFO) \
- && SYMBOL_REFERENCES_LOCAL_P ((INFO), (H))) \
- || (ELF_ST_VISIBILITY ((H)->other) \
- && (H)->root.type == bfd_link_hash_undefweak))
- /* TRUE if this symbol isn't defined by a shared object. */
- #define SYMBOL_DEFINED_NON_SHARED_P(H) \
- ((H)->def_regular \
- || (H)->root.linker_def \
- || (H)->root.ldscript_def \
- || ((struct elf_x86_link_hash_entry *) (H))->linker_def \
- || ELF_COMMON_DEF_P (H))
- /* Return TRUE if the symbol described by a linker hash entry H is
- going to be absolute. Similar to bfd_is_abs_symbol, but excluding
- all linker-script defined symbols. */
- #define ABS_SYMBOL_P(H) \
- (bfd_is_abs_symbol (&(H)->root) && !(H)->root.ldscript_def)
- /* TRUE if relative relocation should be generated. GOT reference to
- global symbol in PIC will lead to dynamic symbol. It becomes a
- problem when "time" or "times" is defined as a variable in an
- executable, clashing with functions of the same name in libc. If a
- symbol isn't undefined weak symbol, don't make it dynamic in PIC and
- generate relative relocation. Don't generate relative relocation
- against non-preemptible absolute symbol. */
- #define GENERATE_RELATIVE_RELOC_P(INFO, H) \
- ((H)->dynindx == -1 \
- && !(H)->forced_local \
- && (H)->root.type != bfd_link_hash_undefweak \
- && bfd_link_pic (INFO) \
- && !ABS_SYMBOL_P (H))
- /* TRUE if this is a pointer reference to a local IFUNC. */
- #define POINTER_LOCAL_IFUNC_P(INFO, H) \
- ((H)->dynindx == -1 \
- || (H)->forced_local \
- || bfd_link_executable (INFO))
- /* TRUE if this is a PLT reference to a local IFUNC. */
- #define PLT_LOCAL_IFUNC_P(INFO, H) \
- ((H)->dynindx == -1 \
- || ((bfd_link_executable (INFO) \
- || ELF_ST_VISIBILITY ((H)->other) != STV_DEFAULT) \
- && (H)->def_regular \
- && (H)->type == STT_GNU_IFUNC))
- /* TRUE if TLS IE->LE transition is OK. */
- #define TLS_TRANSITION_IE_TO_LE_P(INFO, H, TLS_TYPE) \
- (bfd_link_executable (INFO) \
- && (H) != NULL \
- && (H)->dynindx == -1 \
- && (TLS_TYPE & GOT_TLS_IE))
- /* Verify that the symbol has an entry in the procedure linkage table. */
- #define VERIFY_PLT_ENTRY(INFO, H, PLT, GOTPLT, RELPLT, LOCAL_UNDEFWEAK) \
- do \
- { \
- if (((H)->dynindx == -1 \
- && !LOCAL_UNDEFWEAK \
- && !(((H)->forced_local || bfd_link_executable (INFO)) \
- && (H)->def_regular \
- && (H)->type == STT_GNU_IFUNC)) \
- || (PLT) == NULL \
- || (GOTPLT) == NULL \
- || (RELPLT) == NULL) \
- abort (); \
- } \
- while (0);
- /* Verify that the symbol supports copy relocation. */
- #define VERIFY_COPY_RELOC(H, HTAB) \
- do \
- { \
- if ((H)->dynindx == -1 \
- || ((H)->root.type != bfd_link_hash_defined \
- && (H)->root.type != bfd_link_hash_defweak) \
- || (HTAB)->elf.srelbss == NULL \
- || (HTAB)->elf.sreldynrelro == NULL) \
- abort (); \
- } \
- while (0);
- /* x86 ELF linker hash entry. */
- struct elf_x86_link_hash_entry
- {
- struct elf_link_hash_entry elf;
- unsigned char tls_type;
- /* Bit 0: Symbol has no GOT nor PLT relocations.
- Bit 1: Symbol has non-GOT/non-PLT relocations in text sections.
- zero_undefweak is initialized to 1 and undefined weak symbol
- should be resolved to 0 if zero_undefweak > 0. */
- unsigned int zero_undefweak : 2;
- /* Don't call finish_dynamic_symbol on this symbol. */
- unsigned int no_finish_dynamic_symbol : 1;
- /* R_*_RELATIVE relocation in GOT for this symbol has been
- processed. */
- unsigned int got_relative_reloc_done : 1;
- /* TRUE if symbol is __tls_get_addr. */
- unsigned int tls_get_addr : 1;
- /* TRUE if symbol is defined as a protected symbol. */
- unsigned int def_protected : 1;
- /* 0: Symbol references are unknown.
- 1: Symbol references aren't local.
- 2: Symbol references are local.
- */
- unsigned int local_ref : 2;
- /* TRUE if symbol is defined by linker. */
- unsigned int linker_def : 1;
- /* TRUE if symbol is referenced by a non-GOT/non-PLT relocation in a
- relocatable object file without indirect external access marker. */
- unsigned int non_got_ref_without_indirect_extern_access : 1;
- /* TRUE if symbol is referenced by R_386_GOTOFF relocation. This is
- only used by i386. */
- unsigned int gotoff_ref : 1;
- /* TRUE if a weak symbol with a real definition needs a copy reloc.
- When there is a weak symbol with a real definition, the processor
- independent code will have arranged for us to see the real
- definition first. We need to copy the needs_copy bit from the
- real definition and check it when allowing copy reloc in PIE. This
- is only used by x86-64. */
- unsigned int needs_copy : 1;
- /* Information about the GOT PLT entry. Filled when there are both
- GOT and PLT relocations against the same function. */
- union gotplt_union plt_got;
- /* Information about the second PLT entry. */
- union gotplt_union plt_second;
- /* Offset of the GOTPLT entry reserved for the TLS descriptor,
- starting at the end of the jump table. */
- bfd_vma tlsdesc_got;
- };
- struct elf_x86_lazy_plt_layout
- {
- /* The first entry in a lazy procedure linkage table looks like this. */
- const bfd_byte *plt0_entry;
- unsigned int plt0_entry_size; /* Size of PLT0 entry. */
- /* Later entries in a lazy procedure linkage table look like this. */
- const bfd_byte *plt_entry;
- unsigned int plt_entry_size; /* Size of each PLT entry. */
- /* The TLSDESC entry in a lazy procedure linkage table looks like
- this. This is for x86-64 only. */
- const bfd_byte *plt_tlsdesc_entry;
- unsigned int plt_tlsdesc_entry_size; /* Size of TLSDESC entry. */
- /* Offsets into the TLSDESC entry that are to be replaced with
- GOT+8 and GOT+TDG. These are for x86-64 only. */
- unsigned int plt_tlsdesc_got1_offset;
- unsigned int plt_tlsdesc_got2_offset;
- /* Offset of the end of the PC-relative instructions containing
- plt_tlsdesc_got1_offset and plt_tlsdesc_got2_offset. These
- are for x86-64 only. */
- unsigned int plt_tlsdesc_got1_insn_end;
- unsigned int plt_tlsdesc_got2_insn_end;
- /* Offsets into plt0_entry that are to be replaced with GOT[1] and
- GOT[2]. */
- unsigned int plt0_got1_offset;
- unsigned int plt0_got2_offset;
- /* Offset of the end of the PC-relative instruction containing
- plt0_got2_offset. This is for x86-64 only. */
- unsigned int plt0_got2_insn_end;
- /* Offsets into plt_entry that are to be replaced with... */
- unsigned int plt_got_offset; /* ... address of this symbol in .got. */
- unsigned int plt_reloc_offset; /* ... offset into relocation table. */
- unsigned int plt_plt_offset; /* ... offset to start of .plt. */
- /* Length of the PC-relative instruction containing plt_got_offset.
- This is used for x86-64 only. */
- unsigned int plt_got_insn_size;
- /* Offset of the end of the PC-relative jump to plt0_entry. This is
- used for x86-64 only. */
- unsigned int plt_plt_insn_end;
- /* Offset into plt_entry where the initial value of the GOT entry
- points. */
- unsigned int plt_lazy_offset;
- /* The first entry in a PIC lazy procedure linkage table looks like
- this. */
- const bfd_byte *pic_plt0_entry;
- /* Subsequent entries in a PIC lazy procedure linkage table look
- like this. */
- const bfd_byte *pic_plt_entry;
- /* .eh_frame covering the lazy .plt section. */
- const bfd_byte *eh_frame_plt;
- unsigned int eh_frame_plt_size;
- };
- struct elf_x86_non_lazy_plt_layout
- {
- /* Entries in a non-lazy procedure linkage table look like this. */
- const bfd_byte *plt_entry;
- /* Entries in a PIC non-lazy procedure linkage table look like this.
- This is only used for i386 where absolute PLT and PIC PLT are
- different. */
- const bfd_byte *pic_plt_entry;
- unsigned int plt_entry_size; /* Size of each PLT entry. */
- /* Offsets into plt_entry that are to be replaced with... */
- unsigned int plt_got_offset; /* ... address of this symbol in .got. */
- /* Length of the PC-relative instruction containing plt_got_offset.
- This is used for x86-64 only. */
- unsigned int plt_got_insn_size;
- /* .eh_frame covering the non-lazy .plt section. */
- const bfd_byte *eh_frame_plt;
- unsigned int eh_frame_plt_size;
- };
- struct elf_x86_plt_layout
- {
- /* The first entry in a lazy procedure linkage table looks like this. */
- const bfd_byte *plt0_entry;
- /* Entries in a procedure linkage table look like this. */
- const bfd_byte *plt_entry;
- unsigned int plt_entry_size; /* Size of each PLT entry. */
- /* 1 has PLT0. */
- unsigned int has_plt0;
- /* Offsets into plt_entry that are to be replaced with... */
- unsigned int plt_got_offset; /* ... address of this symbol in .got. */
- /* Length of the PC-relative instruction containing plt_got_offset.
- This is only used for x86-64. */
- unsigned int plt_got_insn_size;
- /* Alignment of the .iplt section. */
- unsigned int iplt_alignment;
- /* .eh_frame covering the .plt section. */
- const bfd_byte *eh_frame_plt;
- unsigned int eh_frame_plt_size;
- };
- /* Values in tls_type of x86 ELF linker hash entry. */
- #define GOT_UNKNOWN 0
- #define GOT_NORMAL 1
- #define GOT_TLS_GD 2
- #define GOT_TLS_IE 4
- #define GOT_TLS_IE_POS 5
- #define GOT_TLS_IE_NEG 6
- #define GOT_TLS_IE_BOTH 7
- #define GOT_TLS_GDESC 8
- #define GOT_ABS 9
- #define GOT_TLS_GD_BOTH_P(type) \
- ((type) == (GOT_TLS_GD | GOT_TLS_GDESC))
- #define GOT_TLS_GD_P(type) \
- ((type) == GOT_TLS_GD || GOT_TLS_GD_BOTH_P (type))
- #define GOT_TLS_GDESC_P(type) \
- ((type) == GOT_TLS_GDESC || GOT_TLS_GD_BOTH_P (type))
- #define GOT_TLS_GD_ANY_P(type) \
- (GOT_TLS_GD_P (type) || GOT_TLS_GDESC_P (type))
- #define elf_x86_hash_entry(ent) \
- ((struct elf_x86_link_hash_entry *)(ent))
- /* Information of an input relocation used to compute its contribution
- to the DT_RELR section size. */
- struct elf_x86_relative_reloc_record
- {
- /* The original relocation info. */
- Elf_Internal_Rela rel;
- /* The input or the GOT section where the relocation is applied. */
- asection *sec;
- /* Local symbol info. NULL for global symbol. */
- Elf_Internal_Sym *sym;
- union
- {
- /* Section where the local symbol is defined. */
- asection *sym_sec;
- /* Global symbol hash. */
- struct elf_link_hash_entry *h;
- } u;
- /* The offset into the output section where the relative relocation
- will be applied at run-time. */
- bfd_vma offset;
- /* The run-time address. */
- bfd_vma address;
- };
- struct elf_x86_relative_reloc_data
- {
- bfd_size_type count;
- bfd_size_type size;
- struct elf_x86_relative_reloc_record *data;
- };
- /* DT_RELR bitmap. */
- struct elf_dt_relr_bitmap
- {
- bfd_size_type count;
- bfd_size_type size;
- union
- {
- /* 32-bit bitmap. */
- uint32_t *elf32;
- /* 64-bit bitmap. */
- uint64_t *elf64;
- } u;
- };
- /* x86 ELF linker hash table. */
- struct elf_x86_link_hash_table
- {
- struct elf_link_hash_table elf;
- /* Short-cuts to get to dynamic linker sections. */
- asection *interp;
- asection *plt_eh_frame;
- asection *plt_second;
- asection *plt_second_eh_frame;
- asection *plt_got;
- asection *plt_got_eh_frame;
- /* Parameters describing PLT generation, lazy or non-lazy. */
- struct elf_x86_plt_layout plt;
- /* Parameters describing lazy PLT generation. */
- const struct elf_x86_lazy_plt_layout *lazy_plt;
- /* Parameters describing non-lazy PLT generation. */
- const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
- union
- {
- bfd_signed_vma refcount;
- bfd_vma offset;
- } tls_ld_or_ldm_got;
- /* The amount of space used by the jump slots in the GOT. */
- bfd_vma sgotplt_jump_table_size;
- /* _TLS_MODULE_BASE_ symbol. */
- struct bfd_link_hash_entry *tls_module_base;
- /* Used by local STT_GNU_IFUNC symbols. */
- htab_t loc_hash_table;
- void * loc_hash_memory;
- /* The index of the next R_X86_64_JUMP_SLOT entry in .rela.plt. */
- bfd_vma next_jump_slot_index;
- /* The index of the next R_X86_64_IRELATIVE entry in .rela.plt. */
- bfd_vma next_irelative_index;
- /* The (unloaded but important) .rel.plt.unloaded section on VxWorks.
- This is used for i386 only. */
- asection *srelplt2;
- /* The index of the next unused R_386_TLS_DESC slot in .rel.plt. This
- is only used for i386. */
- bfd_vma next_tls_desc_index;
- /* DT_RELR bitmap. */
- struct elf_dt_relr_bitmap dt_relr_bitmap;
- /* Relative relocation data. */
- struct elf_x86_relative_reloc_data relative_reloc;
- /* Unaligned relative relocation data. */
- struct elf_x86_relative_reloc_data unaligned_relative_reloc;
- /* Number of relative reloc generation pass. */
- unsigned int generate_relative_reloc_pass;
- /* Value used to fill the unused bytes of the first PLT entry. This
- is only used for i386. */
- bfd_byte plt0_pad_byte;
- /* TRUE if GOT is referenced. */
- unsigned int got_referenced : 1;
- /* TRUE if PLT is PC-relative. PLT in PDE and PC-relative PLT in PIE
- can be used as function 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. */
- unsigned int pcrel_plt : 1;
- bfd_vma (*r_info) (bfd_vma, bfd_vma);
- bfd_vma (*r_sym) (bfd_vma);
- bool (*is_reloc_section) (const char *);
- unsigned int sizeof_reloc;
- unsigned int got_entry_size;
- unsigned int pointer_r_type;
- unsigned int relative_r_type;
- int dynamic_interpreter_size;
- const char *dynamic_interpreter;
- const char *tls_get_addr;
- const char *relative_r_name;
- void (*elf_append_reloc) (bfd *, asection *, Elf_Internal_Rela *);
- void (*elf_write_addend) (bfd *, uint64_t, void *);
- void (*elf_write_addend_in_got) (bfd *, uint64_t, void *);
- /* Options passed from the linker. */
- struct elf_linker_x86_params *params;
- };
- struct elf_x86_init_table
- {
- /* The lazy PLT layout. */
- const struct elf_x86_lazy_plt_layout *lazy_plt;
- /* The non-lazy PLT layout. */
- const struct elf_x86_non_lazy_plt_layout *non_lazy_plt;
- /* The lazy PLT layout for IBT. */
- const struct elf_x86_lazy_plt_layout *lazy_ibt_plt;
- /* The non-lazy PLT layout for IBT. */
- const struct elf_x86_non_lazy_plt_layout *non_lazy_ibt_plt;
- bfd_byte plt0_pad_byte;
- bfd_vma (*r_info) (bfd_vma, bfd_vma);
- bfd_vma (*r_sym) (bfd_vma);
- };
- struct elf_x86_obj_tdata
- {
- struct elf_obj_tdata root;
- /* tls_type for each local got entry. */
- char *local_got_tls_type;
- /* GOTPLT entries for TLS descriptors. */
- bfd_vma *local_tlsdesc_gotent;
- /* R_*_RELATIVE relocation in GOT for this local symbol has been
- processed. */
- char *relative_reloc_done;
- };
- enum elf_x86_plt_type
- {
- plt_non_lazy = 0,
- plt_lazy = 1 << 0,
- plt_pic = 1 << 1,
- plt_second = 1 << 2,
- plt_unknown = -1
- };
- struct elf_x86_plt
- {
- const char *name;
- asection *sec;
- bfd_byte *contents;
- enum elf_x86_plt_type type;
- unsigned int plt_got_offset;
- unsigned int plt_entry_size;
- unsigned int plt_got_insn_size; /* Only used for x86-64. */
- long count;
- };
- /* Set if a relocation is converted from a GOTPCREL relocation. */
- #define R_X86_64_converted_reloc_bit (1 << 7)
- #define elf_x86_tdata(abfd) \
- ((struct elf_x86_obj_tdata *) (abfd)->tdata.any)
- #define elf_x86_local_got_tls_type(abfd) \
- (elf_x86_tdata (abfd)->local_got_tls_type)
- #define elf_x86_local_tlsdesc_gotent(abfd) \
- (elf_x86_tdata (abfd)->local_tlsdesc_gotent)
- #define elf_x86_relative_reloc_done(abfd) \
- (elf_x86_tdata (abfd)->relative_reloc_done)
- #define elf_x86_compute_jump_table_size(htab) \
- ((htab)->elf.srelplt->reloc_count * (htab)->got_entry_size)
- #define is_x86_elf(bfd, htab) \
- (bfd_get_flavour (bfd) == bfd_target_elf_flavour \
- && elf_tdata (bfd) != NULL \
- && elf_object_id (bfd) == (htab)->elf.hash_table_id)
- /* Rename some of the generic section flags to better document how they
- are used here. */
- #define check_relocs_failed sec_flg0
- #define relative_reloc_packed sec_flg1
- extern bool _bfd_x86_elf_mkobject
- (bfd *);
- extern void _bfd_x86_elf_set_tls_module_base
- (struct bfd_link_info *);
- extern bfd_vma _bfd_x86_elf_dtpoff_base
- (struct bfd_link_info *);
- extern bool _bfd_x86_elf_readonly_dynrelocs
- (struct elf_link_hash_entry *, void *);
- extern struct elf_link_hash_entry * _bfd_elf_x86_get_local_sym_hash
- (struct elf_x86_link_hash_table *, bfd *, const Elf_Internal_Rela *,
- bool);
- extern hashval_t _bfd_x86_elf_local_htab_hash
- (const void *);
- extern int _bfd_x86_elf_local_htab_eq
- (const void *, const void *);
- extern struct bfd_hash_entry * _bfd_x86_elf_link_hash_newfunc
- (struct bfd_hash_entry *, struct bfd_hash_table *, const char *);
- extern struct bfd_link_hash_table * _bfd_x86_elf_link_hash_table_create
- (bfd *);
- extern int _bfd_x86_elf_compare_relocs
- (const void *, const void *);
- extern bool _bfd_x86_elf_link_check_relocs
- (bfd *, struct bfd_link_info *);
- extern bool _bfd_x86_elf_check_relocs
- (bfd *, struct bfd_link_info *, asection *,
- const Elf_Internal_Rela *);
- extern bool _bfd_x86_elf_link_relax_section
- (bfd *, asection *, struct bfd_link_info *, bool *);
- extern bool _bfd_elf_x86_size_relative_relocs
- (struct bfd_link_info *, bool *);
- extern bool _bfd_elf_x86_finish_relative_relocs
- (struct bfd_link_info *);
- extern void _bfd_elf32_write_addend (bfd *, uint64_t, void *);
- extern void _bfd_elf64_write_addend (bfd *, uint64_t, void *);
- extern bool _bfd_elf_x86_valid_reloc_p
- (asection *, struct bfd_link_info *, struct elf_x86_link_hash_table *,
- const Elf_Internal_Rela *, struct elf_link_hash_entry *,
- Elf_Internal_Sym *, Elf_Internal_Shdr *, bool *);
- extern bool _bfd_x86_elf_size_dynamic_sections
- (bfd *, struct bfd_link_info *);
- extern struct elf_x86_link_hash_table *_bfd_x86_elf_finish_dynamic_sections
- (bfd *, struct bfd_link_info *);
- extern bool _bfd_x86_elf_always_size_sections
- (bfd *, struct bfd_link_info *);
- extern void _bfd_x86_elf_merge_symbol_attribute
- (struct elf_link_hash_entry *, unsigned int, bool, bool);
- extern void _bfd_x86_elf_copy_indirect_symbol
- (struct bfd_link_info *, struct elf_link_hash_entry *,
- struct elf_link_hash_entry *);
- extern bool _bfd_x86_elf_fixup_symbol
- (struct bfd_link_info *, struct elf_link_hash_entry *);
- extern bool _bfd_x86_elf_hash_symbol
- (struct elf_link_hash_entry *);
- extern bool _bfd_x86_elf_adjust_dynamic_symbol
- (struct bfd_link_info *, struct elf_link_hash_entry *);
- extern void _bfd_x86_elf_hide_symbol
- (struct bfd_link_info *, struct elf_link_hash_entry *, bool);
- extern bool _bfd_x86_elf_link_symbol_references_local
- (struct bfd_link_info *, struct elf_link_hash_entry *);
- extern asection * _bfd_x86_elf_gc_mark_hook
- (asection *, struct bfd_link_info *, Elf_Internal_Rela *,
- struct elf_link_hash_entry *, Elf_Internal_Sym *);
- extern long _bfd_x86_elf_get_synthetic_symtab
- (bfd *, long, long, bfd_vma, struct elf_x86_plt [], asymbol **,
- asymbol **);
- extern enum elf_property_kind _bfd_x86_elf_parse_gnu_properties
- (bfd *, unsigned int, bfd_byte *, unsigned int);
- extern bool _bfd_x86_elf_merge_gnu_properties
- (struct bfd_link_info *, bfd *, bfd *, elf_property *, elf_property *);
- extern void _bfd_x86_elf_link_fixup_gnu_properties
- (struct bfd_link_info *, elf_property_list **);
- extern bfd * _bfd_x86_elf_link_setup_gnu_properties
- (struct bfd_link_info *, struct elf_x86_init_table *);
- extern void _bfd_x86_elf_link_fixup_ifunc_symbol
- (struct bfd_link_info *, struct elf_x86_link_hash_table *,
- struct elf_link_hash_entry *, Elf_Internal_Sym *sym);
- extern void _bfd_x86_elf_link_report_relative_reloc
- (struct bfd_link_info *, asection *, struct elf_link_hash_entry *,
- Elf_Internal_Sym *, const char *, const void *);
- #define bfd_elf64_mkobject \
- _bfd_x86_elf_mkobject
- #define bfd_elf32_mkobject \
- _bfd_x86_elf_mkobject
- #define bfd_elf64_bfd_link_hash_table_create \
- _bfd_x86_elf_link_hash_table_create
- #define bfd_elf32_bfd_link_hash_table_create \
- _bfd_x86_elf_link_hash_table_create
- #define bfd_elf64_bfd_link_check_relocs \
- _bfd_x86_elf_link_check_relocs
- #define bfd_elf32_bfd_link_check_relocs \
- _bfd_x86_elf_link_check_relocs
- #define bfd_elf32_bfd_relax_section \
- _bfd_x86_elf_link_relax_section
- #define bfd_elf64_bfd_relax_section \
- _bfd_x86_elf_link_relax_section
- #define elf_backend_check_relocs \
- _bfd_x86_elf_check_relocs
- #define elf_backend_size_dynamic_sections \
- _bfd_x86_elf_size_dynamic_sections
- #define elf_backend_merge_symbol_attribute \
- _bfd_x86_elf_merge_symbol_attribute
- #define elf_backend_copy_indirect_symbol \
- _bfd_x86_elf_copy_indirect_symbol
- #define elf_backend_fixup_symbol \
- _bfd_x86_elf_fixup_symbol
- #define elf_backend_hash_symbol \
- _bfd_x86_elf_hash_symbol
- #define elf_backend_adjust_dynamic_symbol \
- _bfd_x86_elf_adjust_dynamic_symbol
- #define elf_backend_gc_mark_hook \
- _bfd_x86_elf_gc_mark_hook
- #define elf_backend_omit_section_dynsym \
- _bfd_elf_omit_section_dynsym_all
- #define elf_backend_parse_gnu_properties \
- _bfd_x86_elf_parse_gnu_properties
- #define elf_backend_merge_gnu_properties \
- _bfd_x86_elf_merge_gnu_properties
- #define elf_backend_fixup_gnu_properties \
- _bfd_x86_elf_link_fixup_gnu_properties
- #define elf_backend_size_relative_relocs \
- _bfd_elf_x86_size_relative_relocs
- #define elf_backend_finish_relative_relocs \
- _bfd_elf_x86_finish_relative_relocs
- #define ELF_P_ALIGN ELF_MINPAGESIZE
- /* Allocate x86 GOT info for local symbols. */
- static inline bool
- elf_x86_allocate_local_got_info (bfd *abfd, bfd_size_type count)
- {
- bfd_signed_vma *local_got_refcounts = elf_local_got_refcounts (abfd);
- if (local_got_refcounts == NULL)
- {
- bfd_size_type size = count * (sizeof (bfd_signed_vma)
- + sizeof (bfd_vma)
- + 2 * sizeof(char));
- local_got_refcounts = (bfd_signed_vma *) bfd_zalloc (abfd, size);
- if (local_got_refcounts == NULL)
- return false;
- elf_local_got_refcounts (abfd) = local_got_refcounts;
- elf_x86_local_tlsdesc_gotent (abfd) =
- (bfd_vma *) (local_got_refcounts + count);
- elf_x86_local_got_tls_type (abfd) =
- (char *) (local_got_refcounts + 2 * count);
- elf_x86_relative_reloc_done (abfd) =
- ((char *) (local_got_refcounts + 2 * count)) + count;
- }
- return true;
- }
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