diff options
Diffstat (limited to 'sys-devel/mold/files')
| -rw-r--r-- | sys-devel/mold/files/mold-2.0.0-DT_RELR-dependency.patch | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/sys-devel/mold/files/mold-2.0.0-DT_RELR-dependency.patch b/sys-devel/mold/files/mold-2.0.0-DT_RELR-dependency.patch new file mode 100644 index 000000000000..267afde230d2 --- /dev/null +++ b/sys-devel/mold/files/mold-2.0.0-DT_RELR-dependency.patch @@ -0,0 +1,161 @@ +https://bugs.gentoo.org/911591 +https://bugzilla.mozilla.org/show_bug.cgi?id=1847697 +https://github.com/rui314/mold/issues/653#event-10041847648 +https://github.com/rui314/mold/commit/f467ad1add2ab6e381e0e458f026df197e63d487 + +From f467ad1add2ab6e381e0e458f026df197e63d487 Mon Sep 17 00:00:00 2001 +From: Rui Ueyama <ruiu@bluewhale.systems> +Date: Wed, 9 Aug 2023 11:40:09 +0900 +Subject: [PATCH] Create a symbol version dependency to GLIBC_ABI_DT_RELR + +Fixes https://github.com/rui314/mold/issues/653 +--- + elf/cmdline.cc | 2 ++ + elf/mold.h | 1 + + elf/output-chunks.cc | 44 +++++++++++++++++++++++++----- + test/elf/z-pack-relative-relocs.sh | 16 +++++++++++ + 4 files changed, 56 insertions(+), 7 deletions(-) + create mode 100755 test/elf/z-pack-relative-relocs.sh + +diff --git a/elf/cmdline.cc b/elf/cmdline.cc +index c568ce086..82a0e6869 100644 +--- a/elf/cmdline.cc ++++ b/elf/cmdline.cc +@@ -875,8 +875,10 @@ std::vector<std::string> parse_nonpositional_args(Context<E> &ctx) { + ctx.arg.z_nodefaultlib = true; + } else if (read_z_flag("pack-relative-relocs")) { + ctx.arg.pack_dyn_relocs_relr = true; ++ ctx.arg.z_pack_relative_relocs = true; + } else if (read_z_flag("nopack-relative-relocs")) { + ctx.arg.pack_dyn_relocs_relr = false; ++ ctx.arg.z_pack_relative_relocs = false; + } else if (read_z_flag("separate-loadable-segments")) { + z_separate_code = SEPARATE_LOADABLE_SEGMENTS; + } else if (read_z_flag("separate-code")) { +diff --git a/elf/mold.h b/elf/mold.h +index e5532211c..3a027f1e9 100644 +--- a/elf/mold.h ++++ b/elf/mold.h +@@ -1831,6 +1831,7 @@ struct Context { + bool z_nodefaultlib = false; + bool z_now = false; + bool z_origin = false; ++ bool z_pack_relative_relocs = false; + bool z_relro = true; + bool z_sectionheader = true; + bool z_shstk = false; +diff --git a/elf/output-chunks.cc b/elf/output-chunks.cc +index 726a4da2b..3896a2991 100644 +--- a/elf/output-chunks.cc ++++ b/elf/output-chunks.cc +@@ -2373,12 +2373,13 @@ void VerneedSection<E>::construct(Context<E> &ctx) { + std::tuple(((SharedFile<E> *)b->file)->soname, b->ver_idx); + }); + +- // Resize of .gnu.version ++ // Resize .gnu.version + ctx.versym->contents.resize(ctx.dynsym->symbols.size(), 1); + ctx.versym->contents[0] = 0; + + // Allocate a large enough buffer for .gnu.version_r. +- contents.resize((sizeof(ElfVerneed<E>) + sizeof(ElfVernaux<E>)) * syms.size()); ++ contents.resize((sizeof(ElfVerneed<E>) + sizeof(ElfVernaux<E>)) * ++ (syms.size() + 1)); + + // Fill .gnu.version_r. + u8 *buf = (u8 *)&contents[0]; +@@ -2394,14 +2395,14 @@ void VerneedSection<E>::construct(Context<E> &ctx) { + verneed->vn_next = ptr - (u8 *)verneed; + + verneed = (ElfVerneed<E> *)ptr; +- ptr += sizeof(*verneed); ++ ptr += sizeof(ElfVerneed<E>); + verneed->vn_version = 1; + verneed->vn_file = ctx.dynstr->find_string(((SharedFile<E> *)file)->soname); + verneed->vn_aux = sizeof(ElfVerneed<E>); + aux = nullptr; + }; + +- auto add_entry = [&](Symbol<E> *sym) { ++ auto add_entry = [&](std::string_view verstr) { + verneed->vn_cnt++; + + if (aux) +@@ -2409,23 +2410,52 @@ void VerneedSection<E>::construct(Context<E> &ctx) { + aux = (ElfVernaux<E> *)ptr; + ptr += sizeof(*aux); + +- std::string_view verstr = sym->get_version(); + aux->vna_hash = elf_hash(verstr); + aux->vna_other = ++veridx; + aux->vna_name = ctx.dynstr->add_string(verstr); + }; + ++ // Create version entries. + for (i64 i = 0; i < syms.size(); i++) { + if (i == 0 || syms[i - 1]->file != syms[i]->file) { + start_group(syms[i]->file); +- add_entry(syms[i]); ++ add_entry(syms[i]->get_version()); + } else if (syms[i - 1]->ver_idx != syms[i]->ver_idx) { +- add_entry(syms[i]); ++ add_entry(syms[i]->get_version()); + } + + ctx.versym->contents[syms[i]->get_dynsym_idx(ctx)] = veridx; + } + ++ if (ctx.arg.z_pack_relative_relocs) { ++ // If `-z pack-relative-relocs` is specified, we'll create a .relr.dyn ++ // section and store base relocation records to that section instead of ++ // to the usual .rela.dyn section. ++ // ++ // .relr.dyn is relatively new feature and not supported by glibc until ++ // 2.38 which was released in 2022. Executables built with `-z ++ // pack-relative-relocs` don't work and usually crash immediately on ++ // startup if libc doesn't support it. ++ // ++ // In the following code, we'll add a dependency to a dummy version name ++ // "GLIBC_ABI_DT_RELR" so that executables built with the option failed ++ // with a more friendly "version `GLIBC_ABI_DT_RELR' not found" error ++ // message. glibc 2.38 or later knows about this dummy version name and ++ // simply ignores it. ++ auto find_glibc2 = [&]() -> InputFile<E> * { ++ for (Symbol<E> *sym : syms) ++ if (((SharedFile<E> *)sym->file)->soname.starts_with("libc.so.") && ++ sym->get_version().starts_with("GLIBC_2.")) ++ return sym->file; ++ return nullptr; ++ }; ++ ++ if (InputFile<E> *file = find_glibc2()) { ++ start_group(file); ++ add_entry("GLIBC_ABI_DT_RELR"); ++ } ++ } ++ + // Resize .gnu.version_r to fit to its contents. + contents.resize(ptr - buf); + } +diff --git a/test/elf/z-pack-relative-relocs.sh b/test/elf/z-pack-relative-relocs.sh +new file mode 100755 +index 000000000..e09d441e7 +--- /dev/null ++++ b/test/elf/z-pack-relative-relocs.sh +@@ -0,0 +1,16 @@ ++#!/bin/bash ++. $(dirname $0)/common.inc ++ ++cat <<EOF | $CC -o $t/a.o -fPIC -c -xc - ++#include <stdio.h> ++int main() { ++ printf("Hello world\n"); ++} ++EOF ++ ++$CC -B. -o $t/exe $t/a.o -pie -Wl,-z,pack-relative-relocs ++ ++readelf -W -V $t/exe > $t/log ++grep -Fq GLIBC_2. $t/log || skip ++ ++grep -q GLIBC_ABI_DT_RELR $t/log |