diff options
Diffstat (limited to 'bfd/elf32-i386.c')
-rw-r--r-- | bfd/elf32-i386.c | 556 |
1 files changed, 520 insertions, 36 deletions
diff --git a/bfd/elf32-i386.c b/bfd/elf32-i386.c index 6636551..d662816 100644 --- a/bfd/elf32-i386.c +++ b/bfd/elf32-i386.c @@ -617,6 +617,60 @@ static const bfd_byte elf_i386_pic_non_lazy_plt_entry[NON_LAZY_PLT_ENTRY_SIZE] = 0x66, 0x90 /* xchg %ax,%ax */ }; +/* The first entry in an absolute IBT-enabled lazy procedure linkage + table looks like this. */ + +static const bfd_byte elf_i386_lazy_ibt_plt0_entry[LAZY_PLT_ENTRY_SIZE] = +{ + 0xff, 0x35, 0, 0, 0, 0, /* pushl GOT[1] */ + 0xff, 0x25, 0, 0, 0, 0, /* jmp *GOT[2] */ + 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */ +}; + +/* Subsequent entries for an absolute IBT-enabled lazy procedure linkage + table look like this. Subsequent entries for a PIC IBT-enabled lazy + procedure linkage table are the same. */ + +static const bfd_byte elf_i386_lazy_ibt_plt_entry[LAZY_PLT_ENTRY_SIZE] = +{ + 0xf3, 0x0f, 0x1e, 0xfb, /* endbr32 */ + 0x68, 0, 0, 0, 0, /* pushl immediate */ + 0xe9, 0, 0, 0, 0, /* jmp relative */ + 0x66, 0x90 /* xchg %ax,%ax */ +}; + +/* The first entry in a PIC IBT-enabled lazy procedure linkage table + look like. */ + +static const bfd_byte elf_i386_pic_lazy_ibt_plt0_entry[LAZY_PLT_ENTRY_SIZE] = +{ + 0xff, 0xb3, 4, 0, 0, 0, /* pushl 4(%ebx) */ + 0xff, 0xa3, 8, 0, 0, 0, /* jmp *8(%ebx) */ + 0x0f, 0x1f, 0x40, 0x00 /* nopl 0(%rax) */ +}; + +/* Entries for branches with IBT-enabled in the absolute non-lazey + procedure linkage table look like this. They have the same size + as the lazy PLT entry. */ + +static const bfd_byte elf_i386_non_lazy_ibt_plt_entry[LAZY_PLT_ENTRY_SIZE] = +{ + 0xf3, 0x0f, 0x1e, 0xfb, /* endbr32 */ + 0xff, 0x25, 0, 0, 0, 0, /* jmp *name@GOT */ + 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00 /* nopw 0x0(%rax,%rax,1) */ +}; + +/* Entries for branches with IBT-enabled in the PIC non-lazey procedure + linkage table look like this. They have the same size as the lazy + PLT entry. */ + +static const bfd_byte elf_i386_pic_non_lazy_ibt_plt_entry[LAZY_PLT_ENTRY_SIZE] = +{ + 0xf3, 0x0f, 0x1e, 0xfb, /* endbr32 */ + 0xff, 0xa3, 0, 0, 0, 0, /* jmp *name@GOT(%ebx) */ + 0x66, 0x0f, 0x1f, 0x44, 0x00, 0x00 /* nopw 0x0(%rax,%rax,1) */ +}; + /* .eh_frame covering the lazy .plt section. */ static const bfd_byte elf_i386_eh_frame_lazy_plt[] = @@ -656,6 +710,41 @@ static const bfd_byte elf_i386_eh_frame_lazy_plt[] = DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop }; +/* .eh_frame covering the lazy .plt section with IBT-enabled. */ + +static const bfd_byte elf_i386_eh_frame_lazy_ibt_plt[] = +{ + PLT_CIE_LENGTH, 0, 0, 0, /* CIE length */ + 0, 0, 0, 0, /* CIE ID */ + 1, /* CIE version */ + 'z', 'R', 0, /* Augmentation string */ + 1, /* Code alignment factor */ + 0x7c, /* Data alignment factor */ + 8, /* Return address column */ + 1, /* Augmentation size */ + DW_EH_PE_pcrel | DW_EH_PE_sdata4, /* FDE encoding */ + DW_CFA_def_cfa, 4, 4, /* DW_CFA_def_cfa: r4 (esp) ofs 4 */ + DW_CFA_offset + 8, 1, /* DW_CFA_offset: r8 (eip) at cfa-4 */ + DW_CFA_nop, DW_CFA_nop, + + PLT_FDE_LENGTH, 0, 0, 0, /* FDE length */ + PLT_CIE_LENGTH + 8, 0, 0, 0, /* CIE pointer */ + 0, 0, 0, 0, /* R_386_PC32 .plt goes here */ + 0, 0, 0, 0, /* .plt size goes here */ + 0, /* Augmentation size */ + DW_CFA_def_cfa_offset, 8, /* DW_CFA_def_cfa_offset: 8 */ + DW_CFA_advance_loc + 6, /* DW_CFA_advance_loc: 6 to __PLT__+6 */ + DW_CFA_def_cfa_offset, 12, /* DW_CFA_def_cfa_offset: 12 */ + DW_CFA_advance_loc + 10, /* DW_CFA_advance_loc: 10 to __PLT__+16 */ + DW_CFA_def_cfa_expression, /* DW_CFA_def_cfa_expression */ + 11, /* Block length */ + DW_OP_breg4, 4, /* DW_OP_breg4 (esp): 4 */ + DW_OP_breg8, 0, /* DW_OP_breg8 (eip): 0 */ + DW_OP_lit15, DW_OP_and, DW_OP_lit9, DW_OP_ge, + DW_OP_lit2, DW_OP_shl, DW_OP_plus, + DW_CFA_nop, DW_CFA_nop, DW_CFA_nop, DW_CFA_nop +}; + /* .eh_frame covering the non-lazy .plt section. */ static const bfd_byte elf_i386_eh_frame_non_lazy_plt[] = @@ -786,6 +875,34 @@ static const struct elf_i386_non_lazy_plt_layout elf_i386_non_lazy_plt = elf_i386_eh_frame_non_lazy_plt, /* eh_frame_plt */ sizeof (elf_i386_eh_frame_non_lazy_plt) /* eh_frame_plt_size */ }; + +static const struct elf_i386_lazy_plt_layout elf_i386_lazy_ibt_plt = + { + elf_i386_lazy_ibt_plt0_entry, /* plt0_entry */ + sizeof (elf_i386_lazy_ibt_plt0_entry), /* plt0_entry_size */ + 2, /* plt0_got1_offset */ + 8, /* plt0_got2_offset */ + elf_i386_lazy_ibt_plt_entry, /* plt_entry */ + LAZY_PLT_ENTRY_SIZE, /* plt_entry_size */ + 4+2, /* plt_got_offset */ + 4+1, /* plt_reloc_offset */ + 4+6, /* plt_plt_offset */ + 0, /* plt_lazy_offset */ + elf_i386_pic_lazy_ibt_plt0_entry, /* pic_plt0_entry */ + elf_i386_lazy_ibt_plt_entry, /* pic_plt_entry */ + elf_i386_eh_frame_lazy_ibt_plt, /* eh_frame_plt */ + sizeof (elf_i386_eh_frame_lazy_ibt_plt) /* eh_frame_plt_size */ + }; + +static const struct elf_i386_non_lazy_plt_layout elf_i386_non_lazy_ibt_plt = + { + elf_i386_non_lazy_ibt_plt_entry, /* plt_entry */ + elf_i386_pic_non_lazy_ibt_plt_entry,/* pic_plt_entry */ + LAZY_PLT_ENTRY_SIZE, /* plt_entry_size */ + 4+2, /* plt_got_offset */ + elf_i386_eh_frame_non_lazy_plt, /* eh_frame_plt */ + sizeof (elf_i386_eh_frame_non_lazy_plt) /* eh_frame_plt_size */ + }; /* On VxWorks, the .rel.plt.unloaded section has absolute relocations @@ -889,6 +1006,9 @@ struct elf_i386_link_hash_entry 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; @@ -937,6 +1057,8 @@ struct elf_i386_link_hash_table /* 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; @@ -2644,12 +2766,29 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) here if it is defined and referenced in a non-shared object. */ if (h->type == STT_GNU_IFUNC && h->def_regular) - return _bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs, - &htab->readonly_dynrelocs_against_ifunc, - plt_entry_size, - (htab->plt.has_plt0 * + { + if (_bfd_elf_allocate_ifunc_dyn_relocs (info, h, &eh->dyn_relocs, + &htab->readonly_dynrelocs_against_ifunc, + plt_entry_size, + (htab->plt.has_plt0 * plt_entry_size), - 4, TRUE); + 4, TRUE)) + { + asection *s = htab->plt_second; + if (h->plt.offset != (bfd_vma) -1 && s != NULL) + { + /* Use the second PLT section if it is created. */ + eh->plt_second.offset = s->size; + + /* Make room for this entry in the second PLT section. */ + s->size += htab->non_lazy_plt->plt_entry_size; + } + + return TRUE; + } + else + return FALSE; + } /* Don't create the PLT entry if there are only function pointer relocations which can be resolved at run-time. */ else if (htab->elf.dynamic_sections_created @@ -2677,6 +2816,7 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) || WILL_CALL_FINISH_DYNAMIC_SYMBOL (1, 0, h)) { asection *s = htab->elf.splt; + asection *second_s = htab->plt_second; asection *got_s = htab->plt_got; /* If this is the first .plt entry, make room for the special @@ -2688,7 +2828,11 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) if (use_plt_got) eh->plt_got.offset = got_s->size; else - h->plt.offset = s->size; + { + h->plt.offset = s->size; + if (second_s) + eh->plt_second.offset = second_s->size; + } /* If this symbol is not defined in a regular file, and we are not generating a shared library, then set the symbol to this @@ -2707,8 +2851,18 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) } else { - h->root.u.def.section = s; - h->root.u.def.value = h->plt.offset; + if (second_s) + { + /* We need to make a call to the entry of the + second PLT instead of regular PLT entry. */ + h->root.u.def.section = second_s; + h->root.u.def.value = eh->plt_second.offset; + } + else + { + h->root.u.def.section = s; + h->root.u.def.value = h->plt.offset; + } } } @@ -2718,6 +2872,8 @@ elf_i386_allocate_dynrelocs (struct elf_link_hash_entry *h, void *inf) else { s->size += plt_entry_size; + if (second_s) + second_s->size += htab->non_lazy_plt->plt_entry_size; /* We also need to make an entry in the .got.plt section, which will be placed in the .got section by the linker @@ -3370,6 +3526,15 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) && !bfd_is_abs_section (htab->plt_got->output_section)) htab->plt_got_eh_frame->size = htab->non_lazy_plt->eh_frame_plt_size; + + /* Unwind info for the second PLT and .plt.got sections are + identical. */ + if (htab->plt_second_eh_frame != NULL + && htab->plt_second != NULL + && htab->plt_second->size != 0 + && !bfd_is_abs_section (htab->plt_second->output_section)) + htab->plt_second_eh_frame->size + = htab->non_lazy_plt->eh_frame_plt_size; } /* We now have determined the sizes of the various dynamic sections. @@ -3397,9 +3562,11 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) else if (s == htab->elf.sgotplt || s == htab->elf.iplt || s == htab->elf.igotplt + || s == htab->plt_second || s == htab->plt_got || s == htab->plt_eh_frame || s == htab->plt_got_eh_frame + || s == htab->plt_second_eh_frame || s == htab->elf.sdynbss || s == htab->elf.sdynrelro) { @@ -3472,6 +3639,17 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) + PLT_FDE_LEN_OFFSET)); } + if (htab->plt_second_eh_frame != NULL + && htab->plt_second_eh_frame->contents != NULL) + { + memcpy (htab->plt_second_eh_frame->contents, + htab->non_lazy_plt->eh_frame_plt, + htab->plt_second_eh_frame->size); + bfd_put_32 (dynobj, htab->plt_second->size, + (htab->plt_second_eh_frame->contents + + PLT_FDE_LEN_OFFSET)); + } + if (htab->elf.dynamic_sections_created) { /* Add some entries to the .dynamic section. We fill in the @@ -3903,13 +4081,15 @@ elf_i386_relocate_section (bfd *output_bfd, continue; } + eh = (struct elf_i386_link_hash_entry *) h; + /* Since STT_GNU_IFUNC symbol must go through PLT, we handle it here if it is defined in a non-shared object. */ if (h != NULL && h->type == STT_GNU_IFUNC && h->def_regular) { - asection *plt, *gotplt, *base_got; + asection *gotplt, *base_got; bfd_vma plt_index; const char *name; @@ -3926,12 +4106,22 @@ elf_i386_relocate_section (bfd *output_bfd, /* STT_GNU_IFUNC symbol must go through PLT. */ if (htab->elf.splt != NULL) { - plt = htab->elf.splt; + if (htab->plt_second != NULL) + { + resolved_plt = htab->plt_second; + plt_offset = eh->plt_second.offset; + } + else + { + resolved_plt = htab->elf.splt; + plt_offset = h->plt.offset; + } gotplt = htab->elf.sgotplt; } else { - plt = htab->elf.iplt; + resolved_plt = htab->elf.iplt; + plt_offset = h->plt.offset; gotplt = htab->elf.igotplt; } @@ -4031,8 +4221,8 @@ elf_i386_relocate_section (bfd *output_bfd, goto bad_ifunc_reloc; } - relocation = (plt->output_section->vma - + plt->output_offset + h->plt.offset); + relocation = (resolved_plt->output_section->vma + + resolved_plt->output_offset + plt_offset); switch (r_type) { @@ -4126,7 +4316,6 @@ do_ifunc_pointer: } } - eh = (struct elf_i386_link_hash_entry *) h; resolved_to_zero = (eh != NULL && UNDEFINED_WEAK_RESOLVED_TO_ZERO (info, eh->has_got_reloc, @@ -4424,8 +4613,16 @@ disallow_got32: if (h->plt.offset != (bfd_vma) -1) { - resolved_plt = htab->elf.splt; - plt_offset = h->plt.offset; + if (htab->plt_second != NULL) + { + resolved_plt = htab->plt_second; + plt_offset = eh->plt_second.offset; + } + else + { + resolved_plt = htab->elf.splt; + plt_offset = h->plt.offset; + } } else { @@ -5258,6 +5455,7 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, const struct elf_i386_backend_data *abed; struct elf_i386_link_hash_entry *eh; bfd_boolean local_undefweak; + bfd_boolean use_plt_second; htab = elf_i386_hash_table (info); if (htab == NULL) @@ -5266,6 +5464,9 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, abed = get_elf_i386_backend_data (output_bfd); plt_entry_size = htab->plt.plt_entry_size; + /* Use the second PLT section only if there is .plt section. */ + use_plt_second = htab->elf.splt != NULL && htab->plt_second != NULL; + eh = (struct elf_i386_link_hash_entry *) h; if (eh->no_finish_dynamic_symbol) abort (); @@ -5279,11 +5480,11 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, if (h->plt.offset != (bfd_vma) -1) { - bfd_vma plt_index; + bfd_vma plt_index, plt_offset; bfd_vma got_offset; Elf_Internal_Rela rel; bfd_byte *loc; - asection *plt, *gotplt, *relplt; + asection *plt, *resolved_plt, *gotplt, *relplt; /* When building a static executable, use .iplt, .igot.plt and .rel.iplt sections for STT_GNU_IFUNC symbols. */ @@ -5340,13 +5541,33 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, the first slot. */ memcpy (plt->contents + h->plt.offset, htab->plt.plt_entry, plt_entry_size); + + if (use_plt_second) + { + const bfd_byte *plt_entry; + if (bfd_link_pic (info)) + plt_entry = htab->non_lazy_plt->pic_plt_entry; + else + plt_entry = htab->non_lazy_plt->plt_entry; + memcpy (htab->plt_second->contents + eh->plt_second.offset, + plt_entry, htab->non_lazy_plt->plt_entry_size); + + resolved_plt = htab->plt_second; + plt_offset = eh->plt_second.offset; + } + else + { + resolved_plt = plt; + plt_offset = h->plt.offset; + } + if (! bfd_link_pic (info)) { bfd_put_32 (output_bfd, (gotplt->output_section->vma + gotplt->output_offset + got_offset), - plt->contents + h->plt.offset + resolved_plt->contents + plt_offset + htab->plt.plt_got_offset); if (abed->os == is_vxworks) @@ -5370,8 +5591,8 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, loc = (htab->srelplt2->contents + reloc_index * sizeof (Elf32_External_Rel)); - rel.r_offset = (htab->elf.splt->output_section->vma - + htab->elf.splt->output_offset + rel.r_offset = (plt->output_section->vma + + plt->output_offset + h->plt.offset + 2), rel.r_info = ELF32_R_INFO (htab->elf.hgot->indx, R_386_32); bfd_elf32_swap_reloc_out (output_bfd, &rel, loc); @@ -5389,7 +5610,7 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, else { bfd_put_32 (output_bfd, got_offset, - plt->contents + h->plt.offset + resolved_plt->contents + plt_offset + htab->plt.plt_got_offset); } @@ -5577,6 +5798,7 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, else { asection *plt; + bfd_vma plt_offset; if (!h->pointer_equality_needed) abort (); @@ -5584,10 +5806,19 @@ elf_i386_finish_dynamic_symbol (bfd *output_bfd, /* For non-shared object, we can't use .got.plt, which contains the real function addres if we need pointer equality. We load the GOT entry with the PLT entry. */ - plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt; + if (htab->plt_second != NULL) + { + plt = htab->plt_second; + plt_offset = eh->plt_second.offset; + } + else + { + plt = htab->elf.splt ? htab->elf.splt : htab->elf.iplt; + plt_offset = h->plt.offset; + } bfd_put_32 (output_bfd, (plt->output_section->vma - + plt->output_offset + h->plt.offset), + + plt->output_offset + plt_offset), htab->elf.sgot->contents + h->got.offset); return TRUE; } @@ -5868,6 +6099,10 @@ elf_i386_finish_dynamic_sections (bfd *output_bfd, if (htab->plt_got != NULL && htab->plt_got->size > 0) elf_section_data (htab->plt_got->output_section) ->this_hdr.sh_entsize = htab->non_lazy_plt->plt_entry_size; + + if (htab->plt_second != NULL && htab->plt_second->size > 0) + elf_section_data (htab->plt_second->output_section) + ->this_hdr.sh_entsize = htab->non_lazy_plt->plt_entry_size; } /* Fill in the first three entries in the global offset table. */ @@ -5945,6 +6180,35 @@ elf_i386_finish_dynamic_sections (bfd *output_bfd, } } + /* Adjust .eh_frame for the second PLT section. */ + if (htab->plt_second_eh_frame != NULL + && htab->plt_second_eh_frame->contents != NULL) + { + if (htab->plt_second != NULL + && htab->plt_second->size != 0 + && (htab->plt_second->flags & SEC_EXCLUDE) == 0 + && htab->plt_second->output_section != NULL + && htab->plt_second_eh_frame->output_section != NULL) + { + bfd_vma plt_start = htab->plt_second->output_section->vma; + bfd_vma eh_frame_start + = (htab->plt_second_eh_frame->output_section->vma + + htab->plt_second_eh_frame->output_offset + + PLT_FDE_START_OFFSET); + bfd_put_signed_32 (dynobj, plt_start - eh_frame_start, + htab->plt_second_eh_frame->contents + + PLT_FDE_START_OFFSET); + } + if (htab->plt_second_eh_frame->sec_info_type + == SEC_INFO_TYPE_EH_FRAME) + { + if (! _bfd_elf_write_section_eh_frame (output_bfd, info, + htab->plt_second_eh_frame, + htab->plt_second_eh_frame->contents)) + return FALSE; + } + } + if (htab->elf.sgot && htab->elf.sgot->size > 0) elf_section_data (htab->elf.sgot->output_section)->this_hdr.sh_entsize = 4; @@ -6005,6 +6269,7 @@ enum elf_i386_plt_type plt_non_lazy = 0, plt_lazy = 1 << 0, plt_pic = 1 << 1, + plt_second = 1 << 2, plt_unknown = -1 }; @@ -6042,6 +6307,8 @@ elf_i386_get_synthetic_symtab (bfd *abfd, arelent **dynrelbuf; const struct elf_i386_lazy_plt_layout *lazy_plt; const struct elf_i386_non_lazy_plt_layout *non_lazy_plt; + const struct elf_i386_lazy_plt_layout *lazy_ibt_plt; + const struct elf_i386_non_lazy_plt_layout *non_lazy_ibt_plt; asection *plt; bfd_vma got_addr; char *names; @@ -6050,6 +6317,7 @@ elf_i386_get_synthetic_symtab (bfd *abfd, { { ".plt", NULL, NULL, plt_unknown, 0, 0, 0 }, { ".plt.got", NULL, NULL, plt_non_lazy, 0, 0, 0 }, + { ".plt.sec", NULL, NULL, plt_second, 0, 0, 0 }, { NULL, NULL, NULL, plt_non_lazy, 0, 0, 0 } }; @@ -6078,10 +6346,14 @@ elf_i386_get_synthetic_symtab (bfd *abfd, non_lazy_plt = NULL; /* Silence GCC 6. */ lazy_plt = NULL; + non_lazy_ibt_plt = NULL; + lazy_ibt_plt = NULL; switch (get_elf_i386_backend_data (abfd)->os) { case is_normal: non_lazy_plt = &elf_i386_non_lazy_plt; + lazy_ibt_plt = &elf_i386_lazy_ibt_plt; + non_lazy_ibt_plt = &elf_i386_non_lazy_ibt_plt; /* Fall through */ case is_vxworks: lazy_plt = &elf_i386_lazy_plt; @@ -6118,10 +6390,30 @@ elf_i386_get_synthetic_symtab (bfd *abfd, /* Match lazy PLT first. */ if (memcmp (plt_contents, lazy_plt->plt0_entry, lazy_plt->plt0_got1_offset) == 0) - plt_type = plt_lazy; + { + /* The fist entry in the lazy IBT PLT is the same as the + normal lazy PLT. */ + if (lazy_ibt_plt != NULL + && (memcmp (plt_contents + lazy_ibt_plt->plt_entry_size, + lazy_ibt_plt->plt_entry, + lazy_ibt_plt->plt_got_offset) == 0)) + plt_type = plt_lazy | plt_second; + else + plt_type = plt_lazy; + } else if (memcmp (plt_contents, lazy_plt->pic_plt0_entry, lazy_plt->plt0_got1_offset) == 0) - plt_type = plt_lazy | plt_pic; + { + /* The fist entry in the PIC lazy IBT PLT is the same as + the normal PIC lazy PLT. */ + if (lazy_ibt_plt != NULL + && (memcmp (plt_contents + lazy_ibt_plt->plt_entry_size, + lazy_ibt_plt->pic_plt_entry, + lazy_ibt_plt->plt_got_offset) == 0)) + plt_type = plt_lazy | plt_pic | plt_second; + else + plt_type = plt_lazy | plt_pic; + } } if (non_lazy_plt != NULL @@ -6136,6 +6428,27 @@ elf_i386_get_synthetic_symtab (bfd *abfd, plt_type = plt_pic; } + if ((non_lazy_ibt_plt != NULL) + && (plt_type == plt_unknown || plt_type == plt_second)) + { + if (memcmp (plt_contents, + non_lazy_ibt_plt->plt_entry, + non_lazy_ibt_plt->plt_got_offset) == 0) + { + /* Match IBT PLT. */ + plt_type = plt_second; + non_lazy_plt = non_lazy_ibt_plt; + } + else if (memcmp (plt_contents, + non_lazy_ibt_plt->pic_plt_entry, + non_lazy_ibt_plt->plt_got_offset) == 0) + { + /* Match PIC IBT PLT. */ + plt_type = plt_second | plt_pic; + non_lazy_plt = non_lazy_ibt_plt; + } + } + if (plt_type == plt_unknown) continue; @@ -6156,9 +6469,16 @@ elf_i386_get_synthetic_symtab (bfd *abfd, i = 0; } - n = plt->size / plts[j].plt_entry_size; - plts[j].count = n; - count += n - i; + /* Skip lazy PLT when the second PLT is used. */ + if ((plt_type & (plt_lazy | plt_second)) + == (plt_lazy | plt_second)) + plts[j].count = 0; + else + { + n = plt->size / plts[j].plt_entry_size; + plts[j].count = n; + count += n - i; + } plts[j].contents = plt_contents; @@ -6363,12 +6683,15 @@ elf_i386_parse_gnu_properties (bfd *abfd, unsigned int type, { case GNU_PROPERTY_X86_ISA_1_USED: case GNU_PROPERTY_X86_ISA_1_NEEDED: + case GNU_PROPERTY_X86_FEATURE_1_AND: if (datasz != 4) { _bfd_error_handler ((type == GNU_PROPERTY_X86_ISA_1_USED ? _("error: %B: <corrupt x86 ISA used size: 0x%x>") - : _("error: %B: <corrupt x86 ISA needed size: 0x%x>")), + : (type == GNU_PROPERTY_X86_ISA_1_NEEDED + ? _("error: %B: <corrupt x86 ISA needed size: 0x%x>") + : _("error: %B: <corrupt x86 feature size: 0x%x>"))), abfd, datasz); return property_corrupt; } @@ -6390,12 +6713,12 @@ elf_i386_parse_gnu_properties (bfd *abfd, unsigned int type, should be merged with ABFD. */ static bfd_boolean -elf_i386_merge_gnu_properties (struct bfd_link_info *info ATTRIBUTE_UNUSED, +elf_i386_merge_gnu_properties (struct bfd_link_info *info, bfd *abfd ATTRIBUTE_UNUSED, elf_property *aprop, elf_property *bprop) { - unsigned int number; + unsigned int number, features; bfd_boolean updated = FALSE; unsigned int pr_type = aprop != NULL ? aprop->pr_type : bprop->pr_type; @@ -6417,6 +6740,53 @@ elf_i386_merge_gnu_properties (struct bfd_link_info *info ATTRIBUTE_UNUSED, } break; + case GNU_PROPERTY_X86_FEATURE_1_AND: + /* Only one of APROP and BPROP can be NULL: + 1. APROP & BPROP when both APROP and BPROP aren't NULL. + 2. If APROP is NULL, remove x86 feature. + 3. Otherwise, do nothing. + */ + if (aprop != NULL && bprop != NULL) + { + features = 0; + if (info->ibt) + features = GNU_PROPERTY_X86_FEATURE_1_IBT; + number = aprop->u.number; + /* Add GNU_PROPERTY_X86_FEATURE_1_IBT. */ + aprop->u.number = (number & bprop->u.number) | features; + updated = number != (unsigned int) aprop->u.number; + /* Remove the property if all feature bits are cleared. */ + if (aprop->u.number == 0) + aprop->pr_kind = property_remove; + } + else + { + features = 0; + if (info->ibt) + features = GNU_PROPERTY_X86_FEATURE_1_IBT; + if (features) + { + /* Add GNU_PROPERTY_X86_FEATURE_1_IBT. */ + if (aprop != NULL) + { + number = aprop->u.number; + aprop->u.number = number | features; + updated = number != (unsigned int) aprop->u.number; + } + else + { + bprop->u.number |= features; + updated = TRUE; + } + } + else if (aprop != NULL) + { + aprop->pr_kind = property_remove; + updated = TRUE; + } + } + break; + default: /* Never should happen. */ abort (); @@ -6432,11 +6802,72 @@ static bfd * elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) { bfd_boolean normal_target; + bfd_boolean lazy_plt; asection *sec, *pltsec; bfd *dynobj; - unsigned int plt_alignment; + bfd_boolean use_ibt_plt; + unsigned int plt_alignment, features; struct elf_i386_link_hash_table *htab; - bfd *pbfd = _bfd_elf_link_setup_gnu_properties (info); + bfd *pbfd; + + features = 0; + if (info->ibt) + features = GNU_PROPERTY_X86_FEATURE_1_IBT; + if (features) + { + /* Turn on GNU_PROPERTY_X86_FEATURE_1_IBT. */ + bfd *ebfd = NULL; + elf_property *prop; + + for (pbfd = info->input_bfds; + pbfd != NULL; + pbfd = pbfd->link.next) + if (bfd_get_flavour (pbfd) == bfd_target_elf_flavour + && bfd_count_sections (pbfd) != 0) + { + ebfd = pbfd; + + if (elf_properties (pbfd) != NULL) + { + /* Find a normal input file with GNU property note. */ + prop = _bfd_elf_get_property (pbfd, + GNU_PROPERTY_X86_FEATURE_1_AND, + 4); + /* Add GNU_PROPERTY_X86_FEATURE_1_IBT. */ + prop->u.number |= features; + prop->pr_kind = property_number; + break; + } + } + + if (pbfd == NULL && ebfd != NULL) + { + /* Create GNU_PROPERTY_X86_FEATURE_1_IBT if needed. */ + prop = _bfd_elf_get_property (ebfd, + GNU_PROPERTY_X86_FEATURE_1_AND, + 4); + prop->u.number = features; + prop->pr_kind = property_number; + + sec = bfd_make_section_with_flags (ebfd, + NOTE_GNU_PROPERTY_SECTION_NAME, + (SEC_ALLOC + | SEC_LOAD + | SEC_IN_MEMORY + | SEC_READONLY + | SEC_HAS_CONTENTS + | SEC_DATA)); + if (sec == NULL) + info->callbacks->einfo (_("%F: failed to create GNU property section\n")); + + if (!bfd_set_section_alignment (ebfd, sec, 2)) + goto error_alignment; + + elf_section_type (sec) = SHT_NOTE; + } + } + + pbfd = _bfd_elf_link_setup_gnu_properties (info); if (bfd_link_relocatable (info)) return pbfd; @@ -6445,6 +6876,26 @@ elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) if (htab == NULL) return pbfd; + use_ibt_plt = info->ibtplt || info->ibt; + if (!use_ibt_plt && pbfd != NULL) + { + /* Check if GNU_PROPERTY_X86_FEATURE_1_IBT is on. */ + elf_property_list *p; + + /* The property list is sorted in order of type. */ + for (p = elf_properties (pbfd); p; p = p->next) + { + if (GNU_PROPERTY_X86_FEATURE_1_AND == p->property.pr_type) + { + use_ibt_plt = !!(p->property.u.number + & GNU_PROPERTY_X86_FEATURE_1_IBT); + break; + } + else if (GNU_PROPERTY_X86_FEATURE_1_AND < p->property.pr_type) + break; + } + } + dynobj = htab->elf.dynobj; /* Set htab->elf.dynobj here so that there is no need to check and @@ -6476,8 +6927,16 @@ elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) switch (get_elf_i386_backend_data (info->output_bfd)->os) { case is_normal: - htab->lazy_plt = &elf_i386_lazy_plt; - htab->non_lazy_plt = &elf_i386_non_lazy_plt; + if (use_ibt_plt) + { + htab->lazy_plt = &elf_i386_lazy_ibt_plt; + htab->non_lazy_plt = &elf_i386_non_lazy_ibt_plt; + } + else + { + htab->lazy_plt = &elf_i386_lazy_plt; + htab->non_lazy_plt = &elf_i386_non_lazy_plt; + } normal_target = TRUE; break; case is_vxworks: @@ -6500,6 +6959,7 @@ elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) if (htab->non_lazy_plt != NULL && (!htab->plt.has_plt0 || pltsec == NULL)) { + lazy_plt = FALSE; if (bfd_link_pic (info)) htab->plt.plt_entry = htab->non_lazy_plt->pic_plt_entry; @@ -6517,6 +6977,7 @@ elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) } else { + lazy_plt = TRUE; if (bfd_link_pic (info)) { htab->plt.plt0_entry @@ -6605,6 +7066,29 @@ elf_i386_link_setup_gnu_properties (struct bfd_link_info *info) goto error_alignment; htab->plt_got = sec; + + if (lazy_plt) + { + sec = NULL; + + if (use_ibt_plt) + { + /* Create the second PLT for Intel IBT support. IBT + PLT is supported only for non-NaCl target and is + is needed only for lazy binding. */ + sec = bfd_make_section_anyway_with_flags (dynobj, + ".plt.sec", + pltflags); + if (sec == NULL) + info->callbacks->einfo (_("%F: failed to create IBT-enabled PLT section\n")); + + if (!bfd_set_section_alignment (dynobj, sec, + plt_alignment)) + goto error_alignment; + } + + htab->plt_second = sec; + } } if (!info->no_ld_generated_unwind_info) |