From f4cafbd0d73b012a4ba25da223646ec9cc1565cb Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Mon, 1 Jun 2009 12:53:00 +0000 Subject: [PATCH] bfd/ 2009-06-01 H.J. Lu * elf-bfd.h (struct bfd_elf_section_data): Remove indirect_relocs. (_bfd_elf_make_ifunc_reloc_section): Removed. (_bfd_elf_is_ifunc_symbol): Likewise. (_bfd_elf_create_static_ifunc_sections): New. * elflink.c (_bfd_elf_adjust_dynamic_symbol): Move STT_GNU_IFUNC symbol check to ... (elf_link_add_object_symbols): Here. (_bfd_elf_link_hash_hide_symbol): Don't clean plt on STT_GNU_IFUNC symbol. (elf_link_output_extsym): Call elf_backend_finish_dynamic_symbol if a STT_GNU_IFUNC symbol is referenced in a non-shared object. (IFUNC_INFIX): Removed. (get_ifunc_reloc_section_name): Likewise. (_bfd_elf_make_ifunc_reloc_section): Likewise. (_bfd_elf_is_ifunc_symbol): Likewise. (_bfd_elf_create_static_ifunc_sections): New. ld/ 2009-06-01 H.J. Lu * scripttempl/elf.sc (PLT): Add "*(.iplt)". (GOT): Add "*(.igot.plt)a" and "*(.igot)". (GOTPLT): Add "*(.igot)". (__rel_iplt_start): New. (__rel_iplt_end): Likewise. (__rela_iplt_start): Likewise. (__rela_iplt_end): Likewise. --- bfd/ChangeLog | 20 ++++++ bfd/elf-bfd.h | 10 +-- bfd/elflink.c | 174 ++++++++++++++++++++++++++------------------------ ld/ChangeLog | 10 +++ ld/scripttempl/elf.sc | 24 +++++-- 5 files changed, 139 insertions(+), 99 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 24800c534..615530b50 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,23 @@ +2009-06-01 H.J. Lu + + * elf-bfd.h (struct bfd_elf_section_data): Remove indirect_relocs. + (_bfd_elf_make_ifunc_reloc_section): Removed. + (_bfd_elf_is_ifunc_symbol): Likewise. + (_bfd_elf_create_static_ifunc_sections): New. + + * elflink.c (_bfd_elf_adjust_dynamic_symbol): Move STT_GNU_IFUNC + symbol check to ... + (elf_link_add_object_symbols): Here. + (_bfd_elf_link_hash_hide_symbol): Don't clean plt on + STT_GNU_IFUNC symbol. + (elf_link_output_extsym): Call elf_backend_finish_dynamic_symbol + if a STT_GNU_IFUNC symbol is referenced in a non-shared object. + (IFUNC_INFIX): Removed. + (get_ifunc_reloc_section_name): Likewise. + (_bfd_elf_make_ifunc_reloc_section): Likewise. + (_bfd_elf_is_ifunc_symbol): Likewise. + (_bfd_elf_create_static_ifunc_sections): New. + 2009-05-29 H.J. Lu * elf32-i386.c (link_hash_newfunc): Add elf_i386_ prefix. diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index adac206e4..258d11c1f 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -1299,9 +1299,6 @@ struct bfd_elf_section_data /* A pointer to the bfd section used for dynamic relocs. */ asection *sreloc; - /* A pointer to the bfd section used for dynamic relocs against ifunc symbols. */ - asection *indirect_relocs; - union { /* Group name, if this section is a member of a group. */ const char *name; @@ -2149,15 +2146,12 @@ extern int _bfd_elf_obj_attrs_arg_type (bfd *, int, int); extern void _bfd_elf_parse_attributes (bfd *, Elf_Internal_Shdr *); extern bfd_boolean _bfd_elf_merge_object_attributes (bfd *, bfd *); -extern asection * _bfd_elf_make_ifunc_reloc_section - (bfd *, asection *, bfd *, unsigned int); +extern bfd_boolean _bfd_elf_create_static_ifunc_sections + (bfd *, struct bfd_link_info *); /* Large common section. */ extern asection _bfd_elf_large_com_section; -extern bfd_boolean _bfd_elf_is_ifunc_symbol - (bfd *, struct elf_link_hash_entry *); - /* This is the condition under which finish_dynamic_symbol will be called. If our finish_dynamic_symbol isn't called, we'll need to do something about initializing any .plt and .got entries in relocate_section. */ diff --git a/bfd/elflink.c b/bfd/elflink.c index cb5ca0940..d18280764 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -2675,13 +2675,6 @@ _bfd_elf_adjust_dynamic_symbol (struct elf_link_hash_entry *h, void *data) dynobj = elf_hash_table (eif->info)->dynobj; bed = get_elf_backend_data (dynobj); - - if (h->type == STT_GNU_IFUNC - && (bed->elf_osabi == ELFOSABI_LINUX - /* GNU/Linux is still using the default value 0. */ - || bed->elf_osabi == ELFOSABI_NONE)) - h->needs_plt = 1; - if (! (*bed->elf_backend_adjust_dynamic_symbol) (eif->info, h)) { eif->failed = TRUE; @@ -4295,6 +4288,10 @@ elf_link_add_object_symbols (bfd *abfd, struct bfd_link_info *info) h->type = ELF_ST_TYPE (isym->st_info); } + /* STT_GNU_IFUNC symbol must go through PLT. */ + if (h->type == STT_GNU_IFUNC) + h->needs_plt = 1; + /* Merge st_other field. */ elf_merge_st_other (abfd, h, isym, definition, dynamic); @@ -6669,8 +6666,12 @@ _bfd_elf_link_hash_hide_symbol (struct bfd_link_info *info, struct elf_link_hash_entry *h, bfd_boolean force_local) { - h->plt = elf_hash_table (info)->init_plt_offset; - h->needs_plt = 0; + /* STT_GNU_IFUNC symbol must go through PLT. */ + if (h->type != STT_GNU_IFUNC) + { + h->plt = elf_hash_table (info)->init_plt_offset; + h->needs_plt = 0; + } if (force_local) { h->forced_local = 1; @@ -8649,14 +8650,18 @@ elf_link_output_extsym (struct elf_link_hash_entry *h, void *data) /* Give the processor backend a chance to tweak the symbol value, and also to finish up anything that needs to be done for this symbol. FIXME: Not calling elf_backend_finish_dynamic_symbol for - forced local syms when non-shared is due to a historical quirk. */ - if ((h->dynindx != -1 - || h->forced_local) - && ((finfo->info->shared - && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT - || h->root.type != bfd_link_hash_undefweak)) - || !h->forced_local) - && elf_hash_table (finfo->info)->dynamic_sections_created) + forced local syms when non-shared is due to a historical quirk. + STT_GNU_IFUNC symbol must go through PLT. */ + if ((h->type == STT_GNU_IFUNC + && h->ref_regular + && !finfo->info->relocatable) + || ((h->dynindx != -1 + || h->forced_local) + && ((finfo->info->shared + && (ELF_ST_VISIBILITY (h->other) == STV_DEFAULT + || h->root.type != bfd_link_hash_undefweak)) + || !h->forced_local) + && elf_hash_table (finfo->info)->dynamic_sections_created)) { if (! ((*bed->elf_backend_finish_dynamic_symbol) (finfo->output_bfd, finfo->info, h, &sym))) @@ -12487,88 +12492,87 @@ _bfd_elf_make_dynamic_reloc_section (asection * sec, return reloc_sec; } -/* Returns the name of the ifunc using dynamic reloc section associated with SEC. */ -#define IFUNC_INFIX ".ifunc" +/* Create sections needed by STT_GNU_IFUNC symbol for static + executables. */ -static const char * -get_ifunc_reloc_section_name (bfd * abfd, - asection * sec) +bfd_boolean +_bfd_elf_create_static_ifunc_sections (bfd *abfd, + struct bfd_link_info *info) { - const char * dot; - char * name; - const char * base_name; - unsigned int strndx = elf_elfheader (abfd)->e_shstrndx; - unsigned int shnam = elf_section_data (sec)->rel_hdr.sh_name; - - base_name = bfd_elf_string_from_elf_section (abfd, strndx, shnam); - if (base_name == NULL) - return NULL; - - dot = strchr (base_name + 1, '.'); - name = bfd_alloc (abfd, strlen (base_name) + strlen (IFUNC_INFIX) + 1); - sprintf (name, "%.*s%s%s", (int)(dot - base_name), base_name, IFUNC_INFIX, dot); + flagword flags, pltflags; + int ptralign; + asection *s; + const struct elf_backend_data *bed; - return name; -} + /* Should never be called for shared library. */ + BFD_ASSERT (!info->shared); -/* Like _bfd_elf_make_dynamic_reloc_section but it creates a - section for holding relocs against symbols with the STT_GNU_IFUNC - type. The section is attached to the OWNER bfd but it is created - with a name based on SEC from ABFD. */ + /* This function may be called more than once. */ + s = bfd_get_section_by_name (abfd, ".iplt"); + if (s != NULL) + return TRUE; -asection * -_bfd_elf_make_ifunc_reloc_section (bfd * abfd, - asection * sec, - bfd * owner, - unsigned int align) -{ - asection * reloc_sec = elf_section_data (sec)->indirect_relocs; + bed = get_elf_backend_data (abfd); - if (reloc_sec == NULL) - { - const char * name = get_ifunc_reloc_section_name (abfd, sec); + /* We need to create .iplt, .rel[a].iplt, .igot, .igot.plt, */ + flags = bed->dynamic_sec_flags; - if (name == NULL) - return NULL; + pltflags = flags; + if (bed->plt_not_loaded) + /* We do not clear SEC_ALLOC here because we still want the OS to + allocate space for the section; it's just that there's nothing + to read in from the object file. */ + pltflags &= ~ (SEC_CODE | SEC_LOAD | SEC_HAS_CONTENTS); + else + pltflags |= SEC_ALLOC | SEC_CODE | SEC_LOAD; + if (bed->plt_readonly) + pltflags |= SEC_READONLY; - reloc_sec = bfd_get_section_by_name (owner, name); + s = bfd_make_section_with_flags (abfd, ".iplt", pltflags); + if (s == NULL + || ! bfd_set_section_alignment (abfd, s, bed->plt_alignment)) + return FALSE; - if (reloc_sec == NULL) - { - flagword flags; + s = bfd_make_section_with_flags (abfd, + (bed->rela_plts_and_copies_p + ? ".rela.iplt" : ".rel.iplt"), + flags | SEC_READONLY); + if (s == NULL + || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align)) + return FALSE; - flags = (SEC_HAS_CONTENTS | SEC_READONLY | SEC_IN_MEMORY | SEC_LINKER_CREATED); - if ((sec->flags & SEC_ALLOC) != 0) - flags |= SEC_ALLOC | SEC_LOAD; + switch (bed->s->arch_size) + { + case 32: + ptralign = 2; + break; - reloc_sec = bfd_make_section_with_flags (owner, name, flags); - - if (reloc_sec != NULL - && ! bfd_set_section_alignment (owner, reloc_sec, align)) - reloc_sec = NULL; - } + case 64: + ptralign = 3; + break; - elf_section_data (sec)->indirect_relocs = reloc_sec; + default: + bfd_set_error (bfd_error_bad_value); + return FALSE; } - return reloc_sec; -} - -/* Returns true if the hash entry refers to a symbol marked for - indirect handling during reloc processing. */ - -bfd_boolean -_bfd_elf_is_ifunc_symbol (bfd *abfd, struct elf_link_hash_entry *h) -{ - const struct elf_backend_data * bed; - - if (abfd == NULL || h == NULL) - return FALSE; + /* We don't need the .igot section if we have the .igot.plt + section. */ - bed = get_elf_backend_data (abfd); + if (bed->want_got_plt) + { + s = bfd_make_section_with_flags (abfd, ".igot.plt", flags); + if (s == NULL + || !bfd_set_section_alignment (abfd, s, ptralign)) + return FALSE; + } + else + { + s = bfd_make_section_with_flags (abfd, ".igot", flags); + if (s == NULL + || !bfd_set_section_alignment (abfd, s, ptralign)) + return FALSE; + } - /* GNU/Linux is still using the default value ELFOSABI_NONE. */ - return (h->type == STT_GNU_IFUNC - && (bed->elf_osabi == ELFOSABI_LINUX - || bed->elf_osabi == ELFOSABI_NONE)); + return TRUE; } diff --git a/ld/ChangeLog b/ld/ChangeLog index 9c4b54579..306ed8fc4 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,13 @@ +2009-06-01 H.J. Lu + + * scripttempl/elf.sc (PLT): Add "*(.iplt)". + (GOT): Add "*(.igot.plt)a" and "*(.igot)". + (GOTPLT): Add "*(.igot)". + (__rel_iplt_start): New. + (__rel_iplt_end): Likewise. + (__rela_iplt_start): Likewise. + (__rela_iplt_end): Likewise. + 2009-05-27 Dave Korn * deffilep.y (%union): Add new string-type semantic value 'digits'. diff --git a/ld/scripttempl/elf.sc b/ld/scripttempl/elf.sc index 123a9891f..75efa32a0 100644 --- a/ld/scripttempl/elf.sc +++ b/ld/scripttempl/elf.sc @@ -113,15 +113,15 @@ if test -z "${INITIAL_READONLY_SECTIONS}${CREATE_SHLIB}"; then INITIAL_READONLY_SECTIONS=".interp ${RELOCATING-0} : { *(.interp) }" fi if test -z "$PLT"; then - PLT=".plt ${RELOCATING-0} : { *(.plt) }" + PLT=".plt ${RELOCATING-0} : { *(.plt) *(.iplt)}" fi test -n "${DATA_PLT-${BSS_PLT-text}}" && TEXT_PLT=yes if test -z "$GOT"; then if test -z "$SEPARATE_GOTPLT"; then - GOT=".got ${RELOCATING-0} : { *(.got.plt) *(.got) }" + GOT=".got ${RELOCATING-0} : { *(.got.plt) *(.igot.plt) *(.got) *(.igot) }" else - GOT=".got ${RELOCATING-0} : { *(.got) }" - GOTPLT=".got.plt ${RELOCATING-0} : { *(.got.plt) }" + GOT=".got ${RELOCATING-0} : { *(.got) *(.igot) }" + GOTPLT=".got.plt ${RELOCATING-0} : { *(.got.plt) *(.igot.plt) }" fi fi DYNAMIC=".dynamic ${RELOCATING-0} : { *(.dynamic) }" @@ -354,8 +354,20 @@ EOF fi cat >> ldscripts/dyntmp.$$ <