diff options
| -rw-r--r-- | bfd/elf-bfd.h | 1 | ||||
| -rw-r--r-- | bfd/elflink.c | 11 | ||||
| -rw-r--r-- | include/bfdlink.h | 4 | ||||
| -rw-r--r-- | ld/NEWS | 3 | ||||
| -rw-r--r-- | ld/emulparams/dt-relr.sh | 18 | ||||
| -rw-r--r-- | ld/emulparams/elf32_x86_64.sh | 1 | ||||
| -rw-r--r-- | ld/emulparams/elf_i386.sh | 1 | ||||
| -rw-r--r-- | ld/emulparams/elf_x86_64.sh | 1 | ||||
| -rw-r--r-- | ld/ld.texi | 9 | ||||
| -rw-r--r-- | ld/ldelf.c | 9 | ||||
| -rw-r--r-- | ld/ldlang.c | 3 | ||||
| -rw-r--r-- | ld/scripttempl/elf.sc | 4 |
12 files changed, 64 insertions, 1 deletions
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index 0d9c764..7808f87 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h @@ -707,6 +707,7 @@ struct elf_link_hash_table asection *irelplt; asection *irelifunc; asection *dynsym; + asection *srelrdyn; }; /* Returns TRUE if the hash table is a struct elf_link_hash_table. */ diff --git a/bfd/elflink.c b/bfd/elflink.c index 46bff27..17407f2 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -359,6 +359,17 @@ _bfd_elf_link_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info) elf_section_data (s)->this_hdr.sh_entsize = 4; } + if (info->enable_dt_relr) + { + s = bfd_make_section_anyway_with_flags (abfd, ".relr.dyn", + (bed->dynamic_sec_flags + | SEC_READONLY)); + if (s == NULL + || !bfd_set_section_alignment (s, bed->s->log_file_align)) + return false; + elf_hash_table (info)->srelrdyn = s; + } + /* Let the backend create the rest of the sections. This lets the backend set the right flags. The backend will normally create the .got and .plt sections. */ diff --git a/include/bfdlink.h b/include/bfdlink.h index 01f57c2..92e3e32 100644 --- a/include/bfdlink.h +++ b/include/bfdlink.h @@ -413,6 +413,10 @@ struct bfd_link_info /* TRUE if PT_GNU_RELRO segment should be created. */ unsigned int relro: 1; + /* TRUE if DT_RELR should be enabled for compact relative + relocations. */ + unsigned int enable_dt_relr: 1; + /* TRUE if separate code segment should be created. */ unsigned int separate_code: 1; @@ -1,5 +1,8 @@ -*- text -*- +* Add -z pack-relative-relocs/-z no pack-relative-relocs to x86 ELF + linker to pack relative relocations in the DT_RELR section. + * Add support for the LoongArch architecture. * Add -z indirect-extern-access/-z noindirect-extern-access to x86 ELF diff --git a/ld/emulparams/dt-relr.sh b/ld/emulparams/dt-relr.sh new file mode 100644 index 0000000..b2b403c --- /dev/null +++ b/ld/emulparams/dt-relr.sh @@ -0,0 +1,18 @@ +HAVE_DT_RELR=yes +PARSE_AND_LIST_OPTIONS_PACK_RELATIVE_RELOCS=' + fprintf (file, _("\ + -z pack-relative-relocs Pack relative relocations\n")); + fprintf (file, _("\ + -z nopack-relative-relocs Do not pack relative relocations (default)\n")); +' + +PARSE_AND_LIST_ARGS_CASE_Z_PACK_RELATIVE_RELOCS=' + else if (strcmp (optarg, "pack-relative-relocs") == 0) + link_info.enable_dt_relr = true; + else if (strcmp (optarg, "nopack-relative-relocs") == 0) + link_info.enable_dt_relr = false; +' + + +PARSE_AND_LIST_OPTIONS="$PARSE_AND_LIST_OPTIONS $PARSE_AND_LIST_OPTIONS_PACK_RELATIVE_RELOCS" +PARSE_AND_LIST_ARGS_CASE_Z="$PARSE_AND_LIST_ARGS_CASE_Z $PARSE_AND_LIST_ARGS_CASE_Z_PACK_RELATIVE_RELOCS" diff --git a/ld/emulparams/elf32_x86_64.sh b/ld/emulparams/elf32_x86_64.sh index ac0a7aa..4bff412 100644 --- a/ld/emulparams/elf32_x86_64.sh +++ b/ld/emulparams/elf32_x86_64.sh @@ -7,6 +7,7 @@ source_sh ${srcdir}/emulparams/cet.sh source_sh ${srcdir}/emulparams/x86-report-relative.sh source_sh ${srcdir}/emulparams/x86-64-level.sh source_sh ${srcdir}/emulparams/static.sh +source_sh ${srcdir}/emulparams/dt-relr.sh SCRIPT_NAME=elf ELFSIZE=32 OUTPUT_FORMAT="elf32-x86-64" diff --git a/ld/emulparams/elf_i386.sh b/ld/emulparams/elf_i386.sh index 98532e5..ae17bb4 100644 --- a/ld/emulparams/elf_i386.sh +++ b/ld/emulparams/elf_i386.sh @@ -6,6 +6,7 @@ source_sh ${srcdir}/emulparams/cet.sh source_sh ${srcdir}/emulparams/x86-report-relative.sh source_sh ${srcdir}/emulparams/x86-64-level.sh source_sh ${srcdir}/emulparams/static.sh +source_sh ${srcdir}/emulparams/dt-relr.sh SCRIPT_NAME=elf OUTPUT_FORMAT="elf32-i386" NO_RELA_RELOCS=yes diff --git a/ld/emulparams/elf_x86_64.sh b/ld/emulparams/elf_x86_64.sh index 48d0974..5f2743e 100644 --- a/ld/emulparams/elf_x86_64.sh +++ b/ld/emulparams/elf_x86_64.sh @@ -8,6 +8,7 @@ source_sh ${srcdir}/emulparams/x86-report-relative.sh source_sh ${srcdir}/emulparams/x86-64-level.sh source_sh ${srcdir}/emulparams/x86-64-lam.sh source_sh ${srcdir}/emulparams/static.sh +source_sh ${srcdir}/emulparams/dt-relr.sh SCRIPT_NAME=elf ELFSIZE=64 OUTPUT_FORMAT="elf64-x86-64" @@ -1430,6 +1430,15 @@ called. @item origin Specify that the object requires @samp{$ORIGIN} handling in paths. +@item pack-relative-relocs +@itemx nopack-relative-relocs +Generate compact relative relocation in position-independent executable +and shared library. It adds @code{DT_RELR}, @code{DT_RELRSZ} and +@code{DT_RELRENT} entries to the dynamic section. It is ignored when +building position-dependent executable and relocatable output. +@option{nopack-relative-relocs} is the default, which disables compact +relative relocation. Supported for i386 and x86-64. + @item relro @itemx norelro Create an ELF @code{PT_GNU_RELRO} segment header in the object. This @@ -71,6 +71,15 @@ ldelf_after_parse (void) einfo (_("%P: warning: -z dynamic-undefined-weak ignored\n")); link_info.dynamic_undefined_weak = 0; } + + /* Disable DT_RELR if not building PIE nor shared library. */ + if (!bfd_link_pic (&link_info)) + link_info.enable_dt_relr = 0; + + /* Add 3 spare tags for DT_RELR, DT_RELRSZ and DT_RELRENT. */ + if (link_info.enable_dt_relr) + link_info.spare_dynamic_tags += 3; + after_parse_default (); if (link_info.commonpagesize > link_info.maxpagesize) einfo (_("%F%P: common page size (0x%v) > maximum page size (0x%v)\n"), diff --git a/ld/ldlang.c b/ld/ldlang.c index 0af6c60..0a24fd8 100644 --- a/ld/ldlang.c +++ b/ld/ldlang.c @@ -7709,7 +7709,8 @@ lang_find_relro_sections (void) void lang_relax_sections (bool need_layout) { - if (RELAXATION_ENABLED) + /* NB: Also enable relaxation to layout sections for DT_RELR. */ + if (RELAXATION_ENABLED || link_info.enable_dt_relr) { /* We may need more than one relaxation pass. */ int i = link_info.relax_pass; diff --git a/ld/scripttempl/elf.sc b/ld/scripttempl/elf.sc index a9a39ad..f3552a4 100644 --- a/ld/scripttempl/elf.sc +++ b/ld/scripttempl/elf.sc @@ -10,6 +10,7 @@ # empty. # HAVE_NOINIT - Include a .noinit output section in the script. # HAVE_PERSISTENT - Include a .persistent output section in the script. +# HAVE_DT_RELR - Include a .relr.dyn output section in the script. # SMALL_DATA_CTOR - .ctors contains small data. # SMALL_DATA_DTOR - .dtors contains small data. # DATA_ADDR - if end-of-text-plus-one-page isn't right for data start @@ -520,6 +521,9 @@ emit_dyn() fi fi rm -f ldscripts/dyntmp.$$ + if test -n "${COMBRELOC}" && test -n "${HAVE_DT_RELR}"; then + echo " .relr.dyn : { *(.relr.dyn) }" + fi } test -n "${NON_ALLOC_DYN}${SEPARATE_CODE}" || emit_dyn |