diff options
| -rw-r--r-- | bfd/ChangeLog | 24 | ||||
| -rw-r--r-- | bfd/elf32-arm.c | 725 | ||||
| -rw-r--r-- | ld/ChangeLog | 5 | ||||
| -rw-r--r-- | ld/emulparams/armelf_linux_fdpiceabi.sh | 8 |
4 files changed, 731 insertions, 31 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 9b50933..f8525a2 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,6 +1,30 @@ 2018-04-25 Christophe Lyon <christophe.lyon@st.com> Mickaël Guêné <mickael.guene@st.com> + * elf32-arm.c (struct fdpic_local): New. + (elf_arm_obj_tdata): Add local_fdpic_cnts field. + (elf32_arm_local_fdpic_cnts): New. + (struct fdpic_global): New. + (elf32_arm_link_hash_entry): Add fdpic_cnts field. + (elf32_arm_link_hash_table): Add srofixup field. + (arm_elf_add_rofixup): New. + (arm_elf_fill_funcdesc): New. + (elf32_arm_link_hash_newfunc): Handle fdpic_cnts. + (elf32_arm_allocate_local_sym_info): Likewise. + (create_got_section): Create .rofixup section. + (elf32_arm_copy_indirect_symbol): Handle fdpic_cnts. + (bfd_elf32_arm_set_target_params): Handle FDPIC. + (elf32_arm_final_link_relocate): Likewise. + (elf32_arm_check_relocs): Likewise. + (allocate_dynrelocs_for_symbol): Likewise. + (elf32_arm_size_dynamic_sections): Likewise. + (elf32_arm_finish_dynamic_sections): Likewise. + (elf32_arm_output_arch_local_syms): Likewise. + (elf32_arm_fdpic_omit_section_dynsym): New. + +2018-04-25 Christophe Lyon <christophe.lyon@st.com> + Mickaël Guêné <mickael.guene@st.com> + * bfd-in2.c (BFD_RELOC_ARM_GOTFUNCDESC) (BFD_RELOC_ARM_GOTOFFFUNCDESC, BFD_RELOC_ARM_FUNCDESC) (BFD_RELOC_ARM_FUNCDESC_VALUE): New. diff --git a/bfd/elf32-arm.c b/bfd/elf32-arm.c index 3805f71..eef143e 100644 --- a/bfd/elf32-arm.c +++ b/bfd/elf32-arm.c @@ -3001,6 +3001,13 @@ struct arm_local_iplt_info struct elf_dyn_relocs *dyn_relocs; }; +/* Structure to handle FDPIC support for local functions. */ +struct fdpic_local { + unsigned int funcdesc_cnt; + unsigned int gotofffuncdesc_cnt; + int funcdesc_offset; +}; + struct elf_arm_obj_tdata { struct elf_obj_tdata root; @@ -3019,6 +3026,9 @@ struct elf_arm_obj_tdata /* Zero to warn when linking objects with incompatible wchar_t sizes. */ int no_wchar_size_warning; + + /* Maintains FDPIC counters and funcdesc info. */ + struct fdpic_local *local_fdpic_cnts; }; #define elf_arm_tdata(bfd) \ @@ -3033,6 +3043,9 @@ struct elf_arm_obj_tdata #define elf32_arm_local_iplt(bfd) \ (elf_arm_tdata (bfd)->local_iplt) +#define elf32_arm_local_fdpic_cnts(bfd) \ + (elf_arm_tdata (bfd)->local_fdpic_cnts) + #define is_arm_elf(bfd) \ (bfd_get_flavour (bfd) == bfd_target_elf_flavour \ && elf_tdata (bfd) != NULL \ @@ -3047,6 +3060,15 @@ elf32_arm_mkobject (bfd *abfd) #define elf32_arm_hash_entry(ent) ((struct elf32_arm_link_hash_entry *)(ent)) +/* Structure to handle FDPIC support for extern functions. */ +struct fdpic_global { + unsigned int gotofffuncdesc_cnt; + unsigned int gotfuncdesc_cnt; + unsigned int funcdesc_cnt; + int funcdesc_offset; + int gotfuncdesc_offset; +}; + /* Arm ELF linker hash entry. */ struct elf32_arm_link_hash_entry { @@ -3082,6 +3104,9 @@ struct elf32_arm_link_hash_entry /* A pointer to the most recently used stub hash entry against this symbol. */ struct elf32_arm_stub_hash_entry *stub_cache; + + /* Counter for FDPIC relocations against this symbol. */ + struct fdpic_global fdpic_cnts; }; /* Traverse an arm ELF linker hash table. */ @@ -3288,8 +3313,22 @@ struct elf32_arm_link_hash_table /* True if the target system uses FDPIC. */ int fdpic_p; + + /* Fixup section. Used for FDPIC. */ + asection *srofixup; }; +/* Add an FDPIC read-only fixup. */ +static void +arm_elf_add_rofixup (bfd *output_bfd, asection *srofixup, bfd_vma offset) +{ + bfd_vma fixup_offset; + + fixup_offset = srofixup->reloc_count++ * 4; + BFD_ASSERT (fixup_offset < srofixup->size); + bfd_put_32 (output_bfd, offset, srofixup->contents + fixup_offset); +} + static inline int ctz (unsigned int mask) { @@ -3327,6 +3366,57 @@ elf32_arm_popcount (unsigned int mask) #endif } +static void elf32_arm_add_dynreloc (bfd *output_bfd, struct bfd_link_info *info, + asection *sreloc, Elf_Internal_Rela *rel); + +static void +arm_elf_fill_funcdesc(bfd *output_bfd, + struct bfd_link_info *info, + int *funcdesc_offset, + int dynindx, + int offset, + bfd_vma addr, + bfd_vma dynreloc_value, + bfd_vma seg) +{ + if ((*funcdesc_offset & 1) == 0) + { + struct elf32_arm_link_hash_table *globals = elf32_arm_hash_table (info); + asection *sgot = globals->root.sgot; + + if (bfd_link_pic(info)) + { + asection *srelgot = globals->root.srelgot; + Elf_Internal_Rela outrel; + + outrel.r_info = ELF32_R_INFO (dynindx, R_ARM_FUNCDESC_VALUE); + outrel.r_offset = sgot->output_section->vma + sgot->output_offset + offset; + outrel.r_addend = 0; + + elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); + bfd_put_32 (output_bfd, addr, sgot->contents + offset); + bfd_put_32 (output_bfd, seg, sgot->contents + offset + 4); + } + else + { + struct elf_link_hash_entry *hgot = globals->root.hgot; + bfd_vma got_value = hgot->root.u.def.value + + hgot->root.u.def.section->output_section->vma + + hgot->root.u.def.section->output_offset; + + arm_elf_add_rofixup(output_bfd, globals->srofixup, + sgot->output_section->vma + sgot->output_offset + + offset); + arm_elf_add_rofixup(output_bfd, globals->srofixup, + sgot->output_section->vma + sgot->output_offset + + offset + 4); + bfd_put_32 (output_bfd, dynreloc_value, sgot->contents + offset); + bfd_put_32 (output_bfd, got_value, sgot->contents + offset + 4); + } + *funcdesc_offset |= 1; + } +} + /* Create an entry in an ARM ELF linker hash table. */ static struct bfd_hash_entry * @@ -3362,6 +3452,12 @@ elf32_arm_link_hash_newfunc (struct bfd_hash_entry * entry, ret->export_glue = NULL; ret->stub_cache = NULL; + + ret->fdpic_cnts.gotofffuncdesc_cnt = 0; + ret->fdpic_cnts.gotfuncdesc_cnt = 0; + ret->fdpic_cnts.funcdesc_cnt = 0; + ret->fdpic_cnts.funcdesc_offset = -1; + ret->fdpic_cnts.gotfuncdesc_offset = -1; } return (struct bfd_hash_entry *) ret; @@ -3383,11 +3479,15 @@ elf32_arm_allocate_local_sym_info (bfd *abfd) size = num_syms * (sizeof (bfd_signed_vma) + sizeof (struct arm_local_iplt_info *) + sizeof (bfd_vma) - + sizeof (char)); + + sizeof (char) + + sizeof (struct fdpic_local)); data = bfd_zalloc (abfd, size); if (data == NULL) return FALSE; + elf32_arm_local_fdpic_cnts (abfd) = (struct fdpic_local *) data; + data += num_syms * sizeof (struct fdpic_local); + elf_local_got_refcounts (abfd) = (bfd_signed_vma *) data; data += num_syms * sizeof (bfd_signed_vma); @@ -3569,6 +3669,16 @@ create_got_section (bfd *dynobj, struct bfd_link_info *info) if (! _bfd_elf_create_got_section (dynobj, info)) return FALSE; + /* Also create .rofixup. */ + if (htab->fdpic_p) + { + htab->srofixup = bfd_make_section_with_flags (dynobj, ".rofixup", + (SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS + | SEC_IN_MEMORY | SEC_LINKER_CREATED | SEC_READONLY)); + if (htab->srofixup == NULL || ! bfd_set_section_alignment (dynobj, htab->srofixup, 2)) + return FALSE; + } + return TRUE; } @@ -3808,6 +3918,11 @@ elf32_arm_copy_indirect_symbol (struct bfd_link_info *info, edir->plt.noncall_refcount += eind->plt.noncall_refcount; eind->plt.noncall_refcount = 0; + /* Copy FDPIC counters. */ + edir->fdpic_cnts.gotofffuncdesc_cnt += eind->fdpic_cnts.gotofffuncdesc_cnt; + edir->fdpic_cnts.gotfuncdesc_cnt += eind->fdpic_cnts.gotfuncdesc_cnt; + edir->fdpic_cnts.funcdesc_cnt += eind->fdpic_cnts.funcdesc_cnt; + /* We should only allocate a function to .iplt once the final symbol information is known. */ BFD_ASSERT (!eind->is_iplt); @@ -8788,7 +8903,10 @@ bfd_elf32_arm_set_target_params (struct bfd *output_bfd, globals->use_blx |= params->use_blx; globals->vfp11_fix = params->vfp11_denorm_fix; globals->stm32l4xx_fix = params->stm32l4xx_fix; - globals->pic_veneer = params->pic_veneer; + if (globals->fdpic_p) + globals->pic_veneer = 1; + else + globals->pic_veneer = params->pic_veneer; globals->fix_cortex_a8 = params->fix_cortex_a8; globals->fix_arm1176 = params->fix_arm1176; globals->cmse_implib = params->cmse_implib; @@ -10147,7 +10265,8 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, relocations are copied into the output file to be resolved at run time. */ if ((bfd_link_pic (info) - || globals->root.is_relocatable_executable) + || globals->root.is_relocatable_executable + || globals->fdpic_p) && (input_section->flags & SEC_ALLOC) && !(globals->vxworks_p && strcmp (input_section->output_section->name, @@ -10168,6 +10287,7 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, { Elf_Internal_Rela outrel; bfd_boolean skip, relocate; + int isrofixup = 0; if ((r_type == R_ARM_REL32 || r_type == R_ARM_REL32_NOI) && !h->def_regular) @@ -10223,7 +10343,8 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, int symbol; /* This symbol is local, or marked to become local. */ - BFD_ASSERT (r_type == R_ARM_ABS32 || r_type == R_ARM_ABS32_NOI); + BFD_ASSERT (r_type == R_ARM_ABS32 || r_type == R_ARM_ABS32_NOI + || (globals->fdpic_p && !bfd_link_pic(info))); if (globals->symbian_p) { asection *osec; @@ -10269,6 +10390,8 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, must use an R_ARM_IRELATIVE relocation to obtain the correct run-time address. */ outrel.r_info = ELF32_R_INFO (symbol, R_ARM_IRELATIVE); + else if (globals->fdpic_p && !bfd_link_pic(info)) + isrofixup = 1; else outrel.r_info = ELF32_R_INFO (symbol, R_ARM_RELATIVE); if (globals->use_rel) @@ -10277,7 +10400,10 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, outrel.r_addend += dynreloc_value; } - elf32_arm_add_dynreloc (output_bfd, info, sreloc, &outrel); + if (isrofixup) + arm_elf_add_rofixup(output_bfd, globals->srofixup, outrel.r_offset); + else + elf32_arm_add_dynreloc (output_bfd, info, sreloc, &outrel); /* If this reloc is against an external symbol, we do not want to fiddle with the addend. Otherwise, we need to include the symbol @@ -11153,8 +11279,10 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, else { Elf_Internal_Rela outrel; + int isrofixup = 0; - if (h->dynindx != -1 && !SYMBOL_REFERENCES_LOCAL (info, h)) + if (((h->dynindx != -1) || globals->fdpic_p) + && !SYMBOL_REFERENCES_LOCAL (info, h)) { /* If the symbol doesn't resolve locally in a static object, we have an undefined reference. If the @@ -11177,6 +11305,8 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT || h->root.type != bfd_link_hash_undefweak)) outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE); + else if (globals->fdpic_p) + isrofixup = 1; else outrel.r_info = 0; outrel.r_addend = dynreloc_value; @@ -11185,20 +11315,27 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, /* The GOT entry is initialized to zero by default. See if we should install a different value. */ if (outrel.r_addend != 0 - && (outrel.r_info == 0 || globals->use_rel)) + && (outrel.r_info == 0 || globals->use_rel || isrofixup)) { bfd_put_32 (output_bfd, outrel.r_addend, sgot->contents + off); outrel.r_addend = 0; } - if (outrel.r_info != 0) + if (outrel.r_info != 0 && !isrofixup) { outrel.r_offset = (sgot->output_section->vma + sgot->output_offset + off); elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); } + else if (isrofixup) + { + arm_elf_add_rofixup(output_bfd, + elf32_arm_hash_table(info)->srofixup, + sgot->output_section->vma + + sgot->output_offset + off); + } h->got.offset |= 1; } value = sgot->output_offset + off; @@ -11236,6 +11373,14 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE); elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); } + else if (globals->fdpic_p) + { + /* For FDPIC executables, we use rofixup to fix + address at runtime. */ + arm_elf_add_rofixup(output_bfd, globals->srofixup, + sgot->output_section->vma + sgot->output_offset + + off); + } local_got_offsets[r_symndx] |= 1; } @@ -11295,12 +11440,24 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, globals->tls_ldm_got.offset |= 1; } - value = sgot->output_section->vma + sgot->output_offset + off - - (input_section->output_section->vma + input_section->output_offset + rel->r_offset); + if (globals->fdpic_p) + { + bfd_put_32(output_bfd, + globals->root.sgot->output_offset + off, + contents + rel->r_offset); + + return bfd_reloc_ok; + } + else + { + value = sgot->output_section->vma + sgot->output_offset + off + - (input_section->output_section->vma + + input_section->output_offset + rel->r_offset); - return _bfd_final_link_relocate (howto, input_bfd, input_section, - contents, rel->r_offset, value, - rel->r_addend); + return _bfd_final_link_relocate (howto, input_bfd, input_section, + contents, rel->r_offset, value, + rel->r_addend); + } } case R_ARM_TLS_CALL: @@ -11653,9 +11810,23 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, - (input_section->output_section->vma + input_section->output_offset + rel->r_offset)); - return _bfd_final_link_relocate (howto, input_bfd, input_section, - contents, rel->r_offset, value, - rel->r_addend); + if (globals->fdpic_p && (r_type == R_ARM_TLS_GD32 || + r_type == R_ARM_TLS_IE32)) + { + /* For FDPIC relocations, resolve to the offset of the GOT + entry from the start of GOT. */ + bfd_put_32(output_bfd, + globals->root.sgot->output_offset + off, + contents + rel->r_offset); + + return bfd_reloc_ok; + } + else + { + return _bfd_final_link_relocate (howto, input_bfd, input_section, + contents, rel->r_offset, value, + rel->r_addend); + } } case R_ARM_TLS_LE32: @@ -12237,6 +12408,241 @@ elf32_arm_final_link_relocate (reloc_howto_type * howto, *unresolved_reloc_p = FALSE; return bfd_reloc_ok; + case R_ARM_GOTOFFFUNCDESC: + { + if (h == NULL) + { + struct fdpic_local *local_fdpic_cnts = elf32_arm_local_fdpic_cnts(input_bfd); + int dynindx = elf_section_data (sym_sec->output_section)->dynindx; + int offset = local_fdpic_cnts[r_symndx].funcdesc_offset & ~1; + bfd_vma addr = dynreloc_value - sym_sec->output_section->vma; + bfd_vma seg = -1; + + if (bfd_link_pic(info) && dynindx == 0) + abort(); + + /* Resolve relocation. */ + bfd_put_32(output_bfd, (offset + sgot->output_offset) + , contents + rel->r_offset); + /* Emit R_ARM_FUNCDESC_VALUE or two fixups on funcdesc if + not done yet. */ + arm_elf_fill_funcdesc(output_bfd, info, + &local_fdpic_cnts[r_symndx].funcdesc_offset, + dynindx, offset, addr, dynreloc_value, seg); + } + else + { + int dynindx; + int offset = eh->fdpic_cnts.funcdesc_offset & ~1; + bfd_vma addr; + bfd_vma seg = -1; + + /* For static binaries, sym_sec can be null. */ + if (sym_sec) + { + dynindx = elf_section_data (sym_sec->output_section)->dynindx; + addr = dynreloc_value - sym_sec->output_section->vma; + } + else + { + dynindx = 0; + addr = 0; + } + + if (bfd_link_pic(info) && dynindx == 0) + abort(); + + /* This case cannot occur since funcdesc is allocated by + the dynamic loader so we cannot resolve the relocation. */ + if (h->dynindx != -1) + abort(); + + /* Resolve relocation. */ + bfd_put_32(output_bfd, (offset + sgot->output_offset), + contents + rel->r_offset); + /* Emit R_ARM_FUNCDESC_VALUE on funcdesc if not done yet. */ + arm_elf_fill_funcdesc(output_bfd, info, + &eh->fdpic_cnts.funcdesc_offset, + dynindx, offset, addr, dynreloc_value, seg); + } + } + *unresolved_reloc_p = FALSE; + return bfd_reloc_ok; + + case R_ARM_GOTFUNCDESC: + { + if (h != NULL) + { + Elf_Internal_Rela outrel; + + /* Resolve relocation. */ + bfd_put_32(output_bfd, ((eh->fdpic_cnts.gotfuncdesc_offset & ~1) + + sgot->output_offset), + contents + rel->r_offset); + /* Add funcdesc and associated R_ARM_FUNCDESC_VALUE. */ + if(h->dynindx == -1) + { + int dynindx; + int offset = eh->fdpic_cnts.funcdesc_offset & ~1; + bfd_vma addr; + bfd_vma seg = -1; + + /* For static binaries sym_sec can be null. */ + if (sym_sec) + { + dynindx = elf_section_data (sym_sec->output_section)->dynindx; + addr = dynreloc_value - sym_sec->output_section->vma; + } + else + { + dynindx = 0; + addr = 0; + } + + /* Emit R_ARM_FUNCDESC_VALUE on funcdesc if not done yet. */ + arm_elf_fill_funcdesc(output_bfd, info, + &eh->fdpic_cnts.funcdesc_offset, + dynindx, offset, addr, dynreloc_value, seg); + } + + /* Add a dynamic relocation on GOT entry if not already done. */ + if ((eh->fdpic_cnts.gotfuncdesc_offset & 1) == 0) + { + if (h->dynindx == -1) + { + outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE); + if (h->root.type == bfd_link_hash_undefweak) + bfd_put_32(output_bfd, 0, sgot->contents + + (eh->fdpic_cnts.gotfuncdesc_offset & ~1)); + else + bfd_put_32(output_bfd, sgot->output_section->vma + + sgot->output_offset + + (eh->fdpic_cnts.funcdesc_offset & ~1), + sgot->contents + + (eh->fdpic_cnts.gotfuncdesc_offset & ~1)); + } + else + { + outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_FUNCDESC); + } + outrel.r_offset = sgot->output_section->vma + + sgot->output_offset + + (eh->fdpic_cnts.gotfuncdesc_offset & ~1); + outrel.r_addend = 0; + if (h->dynindx == -1 && !bfd_link_pic(info)) + if (h->root.type == bfd_link_hash_undefweak) + arm_elf_add_rofixup(output_bfd, globals->srofixup, -1); + else + arm_elf_add_rofixup(output_bfd, globals->srofixup, outrel.r_offset); + else + elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); + eh->fdpic_cnts.gotfuncdesc_offset |= 1; + } + } + else + { + /* Such relocation on static function should not have been + emitted by the compiler. */ + abort(); + } + } + *unresolved_reloc_p = FALSE; + return bfd_reloc_ok; + + case R_ARM_FUNCDESC: + { + if (h == NULL) + { + struct fdpic_local *local_fdpic_cnts = elf32_arm_local_fdpic_cnts(input_bfd); + Elf_Internal_Rela outrel; + int dynindx = elf_section_data (sym_sec->output_section)->dynindx; + int offset = local_fdpic_cnts[r_symndx].funcdesc_offset & ~1; + bfd_vma addr = dynreloc_value - sym_sec->output_section->vma; + bfd_vma seg = -1; + + if (bfd_link_pic(info) && dynindx == 0) + abort(); + + /* Replace static FUNCDESC relocation with a + R_ARM_RELATIVE dynamic relocation or with a rofixup for + executable. */ + outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE); + outrel.r_offset = input_section->output_section->vma + + input_section->output_offset + rel->r_offset; + outrel.r_addend = 0; + if (bfd_link_pic(info)) + elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); + else + arm_elf_add_rofixup(output_bfd, globals->srofixup, outrel.r_offset); + + bfd_put_32 (input_bfd, sgot->output_section->vma + + sgot->output_offset + offset, hit_data); + + /* Emit R_ARM_FUNCDESC_VALUE on funcdesc if not done yet. */ + arm_elf_fill_funcdesc(output_bfd, info, + &local_fdpic_cnts[r_symndx].funcdesc_offset, + dynindx, offset, addr, dynreloc_value, seg); + } + else + { + if (h->dynindx == -1) + { + int dynindx; + int offset = eh->fdpic_cnts.funcdesc_offset & ~1; + bfd_vma addr; + bfd_vma seg = -1; + Elf_Internal_Rela outrel; + + /* For static binaries sym_sec can be null. */ + if (sym_sec) + { + dynindx = elf_section_data (sym_sec->output_section)->dynindx; + addr = dynreloc_value - sym_sec->output_section->vma; + } + else + { + dynindx = 0; + addr = 0; + } + + if (bfd_link_pic(info) && dynindx == 0) + abort(); + + /* Replace static FUNCDESC relocation with a + R_ARM_RELATIVE dynamic relocation. */ + outrel.r_info = ELF32_R_INFO (0, R_ARM_RELATIVE); + outrel.r_offset = input_section->output_section->vma + + input_section->output_offset + rel->r_offset; + outrel.r_addend = 0; + if (bfd_link_pic(info)) + elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); + else + arm_elf_add_rofixup(output_bfd, globals->srofixup, outrel.r_offset); + + bfd_put_32 (input_bfd, sgot->output_section->vma + + sgot->output_offset + offset, hit_data); + + /* Emit R_ARM_FUNCDESC_VALUE on funcdesc if not done yet. */ + arm_elf_fill_funcdesc(output_bfd, info, + &eh->fdpic_cnts.funcdesc_offset, + dynindx, offset, addr, dynreloc_value, seg); + } + else + { + Elf_Internal_Rela outrel; + + /* Add a dynamic relocation. */ + outrel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_FUNCDESC); + outrel.r_offset = input_section->output_section->vma + + input_section->output_offset + rel->r_offset; + outrel.r_addend = 0; + elf32_arm_add_dynreloc (output_bfd, info, srelgot, &outrel); + } + } + } + *unresolved_reloc_p = FALSE; + return bfd_reloc_ok; + default: return bfd_reloc_notsupported; } @@ -14499,6 +14905,54 @@ elf32_arm_check_relocs (bfd *abfd, struct bfd_link_info *info, r_type = elf32_arm_tls_transition (info, r_type, h); switch (r_type) { + case R_ARM_GOTOFFFUNCDESC: + { + if (h == NULL) + { + if (!elf32_arm_allocate_local_sym_info (abfd)) + return FALSE; + elf32_arm_local_fdpic_cnts(abfd)[r_symndx].gotofffuncdesc_cnt += 1; + elf32_arm_local_fdpic_cnts(abfd)[r_symndx].funcdesc_offset = -1; + } + else + { + eh->fdpic_cnts.gotofffuncdesc_cnt++; + } + } + break; + + case R_ARM_GOTFUNCDESC: + { + if (h == NULL) + { + /* Such a relocation is not supposed to be generated + by gcc on a static function. */ + /* Anyway if needed it could be handled. */ + abort(); + } + else + { + eh->fdpic_cnts.gotfuncdesc_cnt++; + } + } + break; + + case R_ARM_FUNCDESC: + { + if (h == NULL) + { + if (!elf32_arm_allocate_local_sym_info (abfd)) + return FALSE; + elf32_arm_local_fdpic_cnts(abfd)[r_symndx].funcdesc_cnt += 1; + elf32_arm_local_fdpic_cnts(abfd)[r_symndx].funcdesc_offset = -1; + } + else + { + eh->fdpic_cnts.funcdesc_cnt++; + } + } + break; + case R_ARM_GOT32: case R_ARM_GOT_PREL: case R_ARM_TLS_GD32: @@ -14640,7 +15094,8 @@ elf32_arm_check_relocs (bfd *abfd, struct bfd_link_info *info, case R_ARM_THM_MOVT_PREL: /* Should the interworking branches be listed here? */ - if ((bfd_link_pic (info) || htab->root.is_relocatable_executable) + if ((bfd_link_pic (info) || htab->root.is_relocatable_executable + || htab->fdpic_p) && (sec->flags & SEC_ALLOC) != 0) { if (h == NULL @@ -14793,6 +15248,18 @@ elf32_arm_check_relocs (bfd *abfd, struct bfd_link_info *info, if (elf32_arm_howto_from_type (r_type)->pc_relative) p->pc_count += 1; p->count += 1; + if (h == NULL && htab->fdpic_p && !bfd_link_pic(info) + && r_type != R_ARM_ABS32 && r_type != R_ARM_ABS32_NOI) { + /* Here we only support R_ARM_ABS32 and R_ARM_ABS32_NOI + that will become rofixup. */ + /* This is due to the fact that we suppose all will become rofixup. */ + fprintf(stderr, "FDPIC does not yet support %d relocation to become dynamic for executable\n", r_type); + _bfd_error_handler + (_("FDPIC does not yet support %s relocation" + " to become dynamic for executable"), + elf32_arm_howto_table_1[r_type].name); + abort(); + } } } @@ -15455,7 +15922,7 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) /* Make sure this symbol is output as a dynamic symbol. Undefined weak syms won't yet be marked as dynamic. */ - if (h->dynindx == -1 && !h->forced_local + if (htab->root.dynamic_sections_created && h->dynindx == -1 && !h->forced_local && h->root.type == bfd_link_hash_undefweak) { if (! bfd_elf_link_record_dynamic_symbol (info, h)) @@ -15535,7 +16002,8 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) if ((tls_type & GOT_TLS_GD) && indx != 0) elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); } - else if (indx != -1 && !SYMBOL_REFERENCES_LOCAL (info, h)) + else if (((indx != -1) || htab->fdpic_p) + && !SYMBOL_REFERENCES_LOCAL (info, h)) { if (htab->root.dynamic_sections_created) /* Reserve room for the GOT entry's R_ARM_GLOB_DAT relocation. */ @@ -15552,11 +16020,110 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) || h->root.type != bfd_link_hash_undefweak)) /* Reserve room for the GOT entry's R_ARM_RELATIVE relocation. */ elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); + else if (htab->fdpic_p && tls_type == GOT_NORMAL) + /* Reserve room for rofixup for FDPIC executable. */ + /* TLS relocs do not need space since they are completely + resolved. */ + htab->srofixup->size += 4; } } else h->got.offset = (bfd_vma) -1; + /* FDPIC support. */ + if (eh->fdpic_cnts.gotofffuncdesc_cnt > 0) + { + /* Symbol musn't be exported. */ + if (h->dynindx != -1) + abort(); + + /* We only allocate one function descriptor with its associated relocation. */ + if (eh->fdpic_cnts.funcdesc_offset == -1) + { + asection *s = htab->root.sgot; + + eh->fdpic_cnts.funcdesc_offset = s->size; + s->size += 8; + /* We will add an R_ARM_FUNCDESC_VALUE relocation or two rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); + else + htab->srofixup->size += 8; + } + } + + if (eh->fdpic_cnts.gotfuncdesc_cnt > 0) + { + asection *s = htab->root.sgot; + + if (htab->root.dynamic_sections_created && h->dynindx == -1 + && !h->forced_local) + if (! bfd_elf_link_record_dynamic_symbol (info, h)) + return FALSE; + + if (h->dynindx == -1) + { + /* We only allocate one function descriptor with its associated relocation. q */ + if (eh->fdpic_cnts.funcdesc_offset == -1) + { + + eh->fdpic_cnts.funcdesc_offset = s->size; + s->size += 8; + /* We will add an R_ARM_FUNCDESC_VALUE relocation or two rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); + else + htab->srofixup->size += 8; + } + } + + /* Add one entry into the GOT and a R_ARM_FUNCDESC or + R_ARM_RELATIVE/rofixup relocation on it. */ + eh->fdpic_cnts.gotfuncdesc_offset = s->size; + s->size += 4; + if (h->dynindx == -1 && !bfd_link_pic(info)) + htab->srofixup->size += 4; + else + elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); + } + + if (eh->fdpic_cnts.funcdesc_cnt > 0) + { + if (htab->root.dynamic_sections_created && h->dynindx == -1 + && !h->forced_local) + if (! bfd_elf_link_record_dynamic_symbol (info, h)) + return FALSE; + + if (h->dynindx == -1) + { + /* We only allocate one function descriptor with its associated relocation. */ + if (eh->fdpic_cnts.funcdesc_offset == -1) + { + asection *s = htab->root.sgot; + + eh->fdpic_cnts.funcdesc_offset = s->size; + s->size += 8; + /* We will add an R_ARM_FUNCDESC_VALUE relocation or two rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, 1); + else + htab->srofixup->size += 8; + } + } + if (h->dynindx == -1 && !bfd_link_pic(info)) + { + /* For FDPIC executable we replace R_ARM_RELATIVE with a rofixup. */ + htab->srofixup->size += 4 * eh->fdpic_cnts.funcdesc_cnt; + } + else + { + /* Will need one dynamic reloc per reference. will be either + R_ARM_FUNCDESC or R_ARM_RELATIVE for hidden symbols. */ + elf32_arm_allocate_dynrelocs (info, htab->root.srelgot, + eh->fdpic_cnts.funcdesc_cnt); + } + } + /* Allocate stubs for exported Thumb functions on v4t. */ if (!htab->use_blx && h->dynindx != -1 && h->def_regular @@ -15599,7 +16166,7 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) space for pc-relative relocs that have become local due to symbol visibility changes. */ - if (bfd_link_pic (info) || htab->root.is_relocatable_executable) + if (bfd_link_pic (info) || htab->root.is_relocatable_executable || htab->fdpic_p) { /* Relocs that use pc_count are PC-relative forms, which will appear on something like ".long foo - ." or "movw REG, foo - .". We want @@ -15646,7 +16213,7 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) /* Make sure undefined weak symbols are output as a dynamic symbol in PIEs. */ - else if (h->dynindx == -1 + else if (htab->root.dynamic_sections_created && h->dynindx == -1 && !h->forced_local) { if (! bfd_elf_link_record_dynamic_symbol (info, h)) @@ -15702,10 +16269,15 @@ allocate_dynrelocs_for_symbol (struct elf_link_hash_entry *h, void * inf) for (p = eh->dyn_relocs; p != NULL; p = p->next) { asection *sreloc = elf_section_data (p->sec)->sreloc; + if (h->type == STT_GNU_IFUNC && eh->plt.noncall_refcount == 0 && SYMBOL_REFERENCES_LOCAL (info, h)) elf32_arm_allocate_irelocs (info, sreloc, p->count); + else if (h->dynindx != -1 && (!bfd_link_pic(info) || !info->symbolic || !h->def_regular)) + elf32_arm_allocate_dynrelocs (info, sreloc, p->count); + else if (htab->fdpic_p && !bfd_link_pic(info)) + htab->srofixup->size += 4 * p->count; else elf32_arm_allocate_dynrelocs (info, sreloc, p->count); } @@ -15800,6 +16372,7 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, asection *srel; bfd_boolean is_vxworks = htab->vxworks_p; unsigned int symndx; + struct fdpic_local *local_fdpic_cnts; if (! is_arm_elf (ibfd)) continue; @@ -15829,7 +16402,10 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, else if (p->count != 0) { srel = elf_section_data (p->sec)->sreloc; - elf32_arm_allocate_dynrelocs (info, srel, p->count); + if (htab->fdpic_p && !bfd_link_pic(info)) + htab->srofixup->size += 4 * p->count; + else + elf32_arm_allocate_dynrelocs (info, srel, p->count); if ((p->sec->output_section->flags & SEC_READONLY) != 0) info->flags |= DF_TEXTREL; } @@ -15846,15 +16422,54 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, local_iplt_ptr = elf32_arm_local_iplt (ibfd); local_tls_type = elf32_arm_local_got_tls_type (ibfd); local_tlsdesc_gotent = elf32_arm_local_tlsdesc_gotent (ibfd); + local_fdpic_cnts = elf32_arm_local_fdpic_cnts (ibfd); symndx = 0; s = htab->root.sgot; srel = htab->root.srelgot; for (; local_got < end_local_got; ++local_got, ++local_iplt_ptr, ++local_tls_type, - ++local_tlsdesc_gotent, ++symndx) + ++local_tlsdesc_gotent, ++symndx, ++local_fdpic_cnts) { *local_tlsdesc_gotent = (bfd_vma) -1; local_iplt = *local_iplt_ptr; + + /* FDPIC support. */ + if (local_fdpic_cnts->gotofffuncdesc_cnt > 0) + { + if (local_fdpic_cnts->funcdesc_offset == -1) + { + local_fdpic_cnts->funcdesc_offset = s->size; + s->size += 8; + + /* We will add an R_ARM_FUNCDESC_VALUE relocation or two rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, srel, 1); + else + htab->srofixup->size += 8; + } + } + + if (local_fdpic_cnts->funcdesc_cnt > 0) + { + if (local_fdpic_cnts->funcdesc_offset == -1) + { + local_fdpic_cnts->funcdesc_offset = s->size; + s->size += 8; + + /* We will add an R_ARM_FUNCDESC_VALUE relocation or two rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, srel, 1); + else + htab->srofixup->size += 8; + } + + /* We will add n R_ARM_RELATIVE relocations or n rofixups. */ + if (bfd_link_pic(info)) + elf32_arm_allocate_dynrelocs (info, srel, local_fdpic_cnts->funcdesc_cnt); + else + htab->srofixup->size += 4 * local_fdpic_cnts->funcdesc_cnt; + } + if (local_iplt != NULL) { struct elf_dyn_relocs *p; @@ -15929,13 +16544,15 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, && (local_iplt == NULL || local_iplt->arm.noncall_refcount == 0)) elf32_arm_allocate_irelocs (info, srel, 1); - else if (bfd_link_pic (info) || output_bfd->flags & DYNAMIC) + else if (bfd_link_pic (info) || output_bfd->flags & DYNAMIC || htab->fdpic_p) { - if ((bfd_link_pic (info) && !(*local_tls_type & GOT_TLS_GDESC)) - || *local_tls_type & GOT_TLS_GD) + if ((bfd_link_pic (info) && !(*local_tls_type & GOT_TLS_GDESC))) elf32_arm_allocate_dynrelocs (info, srel, 1); + else if (htab->fdpic_p && *local_tls_type & GOT_NORMAL) + htab->srofixup->size += 4; - if (bfd_link_pic (info) && *local_tls_type & GOT_TLS_GDESC) + if ((bfd_link_pic (info) || htab->fdpic_p) + && *local_tls_type & GOT_TLS_GDESC) { elf32_arm_allocate_dynrelocs (info, htab->root.srelplt, 1); @@ -15960,6 +16577,11 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, else htab->tls_ldm_got.offset = -1; + /* At the very end of the .rofixup section is a pointer to the GOT, + reserve space for it. */ + if (htab->fdpic_p && htab->srofixup != NULL) + htab->srofixup->size += 4; + /* Allocate global sym .plt and .got entries, and space for global sym dynamic relocs. */ elf_link_hash_traverse (& htab->root, allocate_dynrelocs_for_symbol, info); @@ -16050,7 +16672,8 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED, && s != htab->root.iplt && s != htab->root.igotplt && s != htab->root.sdynbss - && s != htab->root.sdynrelro) + && s != htab->root.sdynrelro + && s != htab->srofixup) { /* It's not one of our sections, so don't allocate space. */ continue; @@ -16682,6 +17305,21 @@ elf32_arm_finish_dynamic_sections (bfd * output_bfd, struct bfd_link_info * info elf_section_data (sgot->output_section)->this_hdr.sh_entsize = 4; } + /* At the very end of the .rofixup section is a pointer to the GOT. */ + if (htab->fdpic_p && htab->srofixup != NULL) + { + struct elf_link_hash_entry *hgot = htab->root.hgot; + + bfd_vma got_value = hgot->root.u.def.value + + hgot->root.u.def.section->output_section->vma + + hgot->root.u.def.section->output_offset; + + arm_elf_add_rofixup(output_bfd, htab->srofixup, got_value); + + /* Make sure we allocated and generated the same number of fixups. */ + BFD_ASSERT (htab->srofixup->reloc_count * 4 == htab->srofixup->size); + } + return TRUE; } @@ -17301,7 +17939,7 @@ elf32_arm_output_arch_local_syms (bfd *output_bfd, if (!elf32_arm_output_map_sym (&osi, ARM_MAP_THUMB, 16)) return FALSE; } - else if (!htab->symbian_p) + else if (!htab->symbian_p && !htab->fdpic_p) { if (!elf32_arm_output_map_sym (&osi, ARM_MAP_ARM, 0)) return FALSE; @@ -19514,15 +20152,44 @@ elf32_arm_fdpic_link_hash_table_create (bfd *abfd) return ret; } +/* We need dynamic symbols for every section, since segments can + relocate independently. */ +static bfd_boolean +elf32_arm_fdpic_omit_section_dynsym (bfd *output_bfd ATTRIBUTE_UNUSED, + struct bfd_link_info *info + ATTRIBUTE_UNUSED, + asection *p ATTRIBUTE_UNUSED) +{ + switch (elf_section_data (p)->this_hdr.sh_type) + { + case SHT_PROGBITS: + case SHT_NOBITS: + /* If sh_type is yet undecided, assume it could be + SHT_PROGBITS/SHT_NOBITS. */ + case SHT_NULL: + return FALSE; + + /* There shouldn't be section relative relocations + against any other section. */ + default: + return TRUE; + } +} + #undef elf32_bed #define elf32_bed elf32_arm_fdpic_bed #undef bfd_elf32_bfd_link_hash_table_create #define bfd_elf32_bfd_link_hash_table_create elf32_arm_fdpic_link_hash_table_create +#undef elf_backend_omit_section_dynsym +#define elf_backend_omit_section_dynsym elf32_arm_fdpic_omit_section_dynsym + #include "elf32-target.h" + #undef elf_match_priority #undef ELF_OSABI +#undef elf_backend_omit_section_dynsym /* VxWorks Targets. */ diff --git a/ld/ChangeLog b/ld/ChangeLog index e633941..d9900b5 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,6 +1,11 @@ 2018-04-25 Christophe Lyon <christophe.lyon@st.com> Mickaël Guêné <mickael.guene@st.com> + * emulparams/armelf_linux_fdpiceabi.sh: Add .rofixup section. + +2018-04-25 Christophe Lyon <christophe.lyon@st.com> + Mickaël Guêné <mickael.guene@st.com> + * Makefile.am (ALL_EMULATION_SOURCES): Add earmelf_linux_fdpiceabi.c and earmelfb_linux_fdpiceabi.c. (earmelf_linux_fdpiceabi.c, earmelfb_linux_fdpiceabi.c): New rules. diff --git a/ld/emulparams/armelf_linux_fdpiceabi.sh b/ld/emulparams/armelf_linux_fdpiceabi.sh index 104cf38..aa604aa 100644 --- a/ld/emulparams/armelf_linux_fdpiceabi.sh +++ b/ld/emulparams/armelf_linux_fdpiceabi.sh @@ -9,5 +9,9 @@ OTHER_READONLY_SECTIONS=" .ARM.extab ${RELOCATING-0} : { *(.ARM.extab${RELOCATING+* .gnu.linkonce.armextab.*}) } ${RELOCATING+ PROVIDE_HIDDEN (__exidx_start = .); } .ARM.exidx ${RELOCATING-0} : { *(.ARM.exidx${RELOCATING+* .gnu.linkonce.armexidx.*}) } - ${RELOCATING+ PROVIDE_HIDDEN (__exidx_end = .); }" - + ${RELOCATING+ PROVIDE_HIDDEN (__exidx_end = .); } + .rofixup : { + ${RELOCATING+__ROFIXUP_LIST__ = .;} + *(.rofixup) + ${RELOCATING+__ROFIXUP_END__ = .;} +}" |