diff options
| -rw-r--r-- | gold/s390.cc | 269 |
1 files changed, 223 insertions, 46 deletions
diff --git a/gold/s390.cc b/gold/s390.cc index c496018..8e20a41 100644 --- a/gold/s390.cc +++ b/gold/s390.cc @@ -78,6 +78,38 @@ class Output_data_got_plt_s390 : public Output_section_data_build Layout* layout_; }; +// A class to handle the first entry of .got when partial relro is in use. + +template<int size> +class Output_data_got_dynamic_s390 : public Output_section_data_build +{ + public: + Output_data_got_dynamic_s390(Layout* layout) + : Output_section_data_build(size/8), + layout_(layout) + { } + + Output_data_got_dynamic_s390(Layout* layout, off_t data_size) + : Output_section_data_build(data_size, size/8), + layout_(layout) + { } + + protected: + // Write out the PLT data. + void + do_write(Output_file*); + + // Write to a map file. + void + do_print_to_mapfile(Mapfile* mapfile) const + { mapfile->print_output_data(this, "** GOT DYNAMIC"); } + + private: + // A pointer to the Layout class, so that we can find the .dynamic + // section when we write out the GOT section. + Layout* layout_; +}; + // A class to handle the PLT data. template<int size> @@ -90,10 +122,11 @@ class Output_data_plt_s390 : public Output_section_data Output_data_plt_s390(Layout* layout, Output_data_got<size, true>* got, Output_data_got_plt_s390<size>* got_plt, - Output_data_space* got_irelative) + Output_data_space* got_irelative, + Output_section_data_build* got_dynamic) : Output_section_data(4), layout_(layout), irelative_rel_(NULL), got_(got), got_plt_(got_plt), - got_irelative_(got_irelative), count_(0), + got_irelative_(got_irelative), got_dynamic_(got_dynamic), count_(0), irelative_count_(0), free_list_() { this->init(layout); } @@ -101,11 +134,13 @@ class Output_data_plt_s390 : public Output_section_data Output_data_got<size, true>* got, Output_data_got_plt_s390<size>* got_plt, Output_data_space* got_irelative, + Output_section_data_build* got_dynamic, unsigned int plt_count) : Output_section_data((plt_count + 1) * plt_entry_size, 4, false), layout_(layout), irelative_rel_(NULL), got_(got), - got_plt_(got_plt), got_irelative_(got_irelative), count_(plt_count), + got_plt_(got_plt), got_irelative_(got_irelative), + got_dynamic_(got_dynamic), count_(plt_count), irelative_count_(0), free_list_() { this->init(layout); @@ -195,7 +230,8 @@ class Output_data_plt_s390 : public Output_section_data void fill_first_plt_entry(unsigned char* pov, typename elfcpp::Elf_types<size>::Elf_Addr got_address, - typename elfcpp::Elf_types<size>::Elf_Addr plt_address); + typename elfcpp::Elf_types<size>::Elf_Addr plt_address, + unsigned int got_plt_offset); // Fill in a normal PLT entry. Returns the offset into the entry that // should be the initial GOT slot value. @@ -238,6 +274,8 @@ class Output_data_plt_s390 : public Output_section_data Output_data_got_plt_s390<size>* got_plt_; // The part of the .got.plt section used for IRELATIVE relocs. Output_data_space* got_irelative_; + // The header of .got section. + Output_section_data_build* got_dynamic_; // The number of PLT entries. unsigned int count_; // Number of PLT entries with R_TILEGX_IRELATIVE relocs. These @@ -251,6 +289,7 @@ class Output_data_plt_s390 : public Output_section_data static const int plt_entry_size = 0x20; // The first entry in the PLT. static const unsigned char first_plt_entry_32_abs[plt_entry_size]; + static const unsigned char first_plt_entry_32_pic12[plt_entry_size]; static const unsigned char first_plt_entry_32_pic[plt_entry_size]; static const unsigned char first_plt_entry_64[plt_entry_size]; // Other entries in the PLT for an executable. @@ -646,7 +685,7 @@ class Target_s390 : public Sized_target<size, true> got_address() const { gold_assert(this->got_ != NULL); - return this->got_plt_->address(); + return this->got_dynamic_->address(); } typename elfcpp::Elf_types<size>::Elf_Addr @@ -741,6 +780,10 @@ class Target_s390 : public Sized_target<size, true> Output_data_got_plt_s390<size>* got_plt_; // The GOT section for IRELATIVE relocations. Output_data_space* got_irelative_; + // The section containing the first GOT entry (_DYNAMIC) - this is + // Output_data_got_dynamic_s390 if partial relro is in use, same + // as got_plt_ otherwise. + Output_section_data_build* got_dynamic_; // The _GLOBAL_OFFSET_TABLE_ symbol. Symbol* global_offset_table_; // The dynamic reloc section. @@ -1247,18 +1290,18 @@ Output_data_plt_s390<size>::first_plt_entry_32_abs[plt_entry_size] = 0x58, 0x10, 0x10, 0x08, // l %r1, 8(%r1) 0x07, 0xf1, // br %r1 0x00, 0x00, // padding - 0x00, 0x00, 0x00, 0x00, // _GLOBAL_OFFSET_TABLE_ (to fill) + 0x00, 0x00, 0x00, 0x00, // DT_GOTPLT (to fill) 0x00, 0x00, 0x00, 0x00, // padding }; template<int size> const unsigned char -Output_data_plt_s390<size>::first_plt_entry_32_pic[plt_entry_size] = +Output_data_plt_s390<size>::first_plt_entry_32_pic12[plt_entry_size] = { 0x50, 0x10, 0xf0, 0x1c, // st %r1, 28(%r15) - 0x58, 0x10, 0xc0, 0x04, // l %r1, 4(%r12) + 0x58, 0x10, 0xc0, 0x00, // l %r1, DT_GOTPLT@got+4(%r12) (to fill) 0x50, 0x10, 0xf0, 0x18, // st %r1, 24(%r15) - 0x58, 0x10, 0xc0, 0x08, // l %r1, 8(%r12) + 0x58, 0x10, 0xc0, 0x00, // l %r1, DT_GOTPLT@got+8(%r12) (to fill) 0x07, 0xf1, // br %r1 0x00, 0x00, // padding 0x00, 0x00, 0x00, 0x00, // padding @@ -1268,10 +1311,25 @@ Output_data_plt_s390<size>::first_plt_entry_32_pic[plt_entry_size] = template<int size> const unsigned char +Output_data_plt_s390<size>::first_plt_entry_32_pic[plt_entry_size] = +{ + 0x50, 0x10, 0xf0, 0x1c, // st %r1, 28(%r15) + 0x0d, 0x10, // basr %r1, %r0 + 0x5a, 0x10, 0x10, 0x12, // a %r1, 18(%r1) + 0xd2, 0x03, 0xf0, 0x18, 0x10, 0x04, // mvc 24(4,%r15), 4(%r1) + 0x58, 0x10, 0x10, 0x08, // l %r1, 8(%r1) + 0x07, 0xf1, // br %r1 + 0x00, 0x00, // padding + 0x00, 0x00, 0x00, 0x00, // DT_GOTPLT - . + 18 (to fill) + 0x00, 0x00, 0x00, 0x00, // padding +}; + +template<int size> +const unsigned char Output_data_plt_s390<size>::first_plt_entry_64[plt_entry_size] = { 0xe3, 0x10, 0xf0, 0x38, 0x00, 0x24, // stg %r1, 56(%r15) - 0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl %r1, _GLOBAL_OFFSET_TABLE_ (to fill) + 0xc0, 0x10, 0x00, 0x00, 0x00, 0x00, // larl %r1, DT_GOTPLT (to fill) 0xd2, 0x07, 0xf0, 0x30, 0x10, 0x08, // mvc 48(8,%r15), 8(%r1) 0xe3, 0x10, 0x10, 0x10, 0x00, 0x04, // lg %r1, 16(%r1) 0x07, 0xf1, // br %r1 @@ -1284,22 +1342,33 @@ template<int size> void Output_data_plt_s390<size>::fill_first_plt_entry( unsigned char* pov, - typename elfcpp::Elf_types<size>::Elf_Addr got_address, - typename elfcpp::Elf_types<size>::Elf_Addr plt_address) + typename elfcpp::Elf_types<size>::Elf_Addr got_plt_address, + typename elfcpp::Elf_types<size>::Elf_Addr plt_address, + unsigned int got_plt_offset) { if (size == 64) { memcpy(pov, first_plt_entry_64, plt_entry_size); - S390_relocate_functions<size>::pcrela32dbl(pov + 8, got_address, (plt_address + 6)); + S390_relocate_functions<size>::pcrela32dbl(pov + 8, got_plt_address, (plt_address + 6)); } else if (!parameters->options().output_is_position_independent()) { memcpy(pov, first_plt_entry_32_abs, plt_entry_size); - elfcpp::Swap<32, true>::writeval(pov + 24, got_address); + elfcpp::Swap<32, true>::writeval(pov + 24, got_plt_address); } else { - memcpy(pov, first_plt_entry_32_pic, plt_entry_size); + if (got_plt_offset < 0xff8) + { + memcpy(pov, first_plt_entry_32_pic12, plt_entry_size); + S390_relocate_functions<size>::rela12(pov + 6, got_plt_offset + 4); + S390_relocate_functions<size>::rela12(pov + 14, got_plt_offset + 8); + } + else + { + memcpy(pov, first_plt_entry_32_pic, plt_entry_size); + elfcpp::Swap<32, true>::writeval(pov + 24, got_plt_address - (plt_address + 6)); + } } } @@ -1536,9 +1605,12 @@ Output_data_plt_s390<size>::do_write(Output_file* of) // which is where the GOT pointer will point, and where the // three reserved GOT entries are located. typename elfcpp::Elf_types<size>::Elf_Addr got_address - = this->got_plt_->address(); + = this->got_dynamic_->address(); + + unsigned int got_plt_offset = this->got_plt_->address() - got_address; - this->fill_first_plt_entry(pov, got_address, plt_address); + this->fill_first_plt_entry(pov, this->got_plt_->address(), plt_address, + got_plt_offset); pov += this->get_plt_entry_size(); unsigned char* got_pov = got_view; @@ -1547,7 +1619,7 @@ Output_data_plt_s390<size>::do_write(Output_file* of) unsigned int plt_offset = this->get_plt_entry_size(); unsigned int plt_rel_offset = 0; - unsigned int got_offset = 3 * size / 8; + unsigned int got_offset = 3 * size / 8 + got_plt_offset; const unsigned int count = this->count_ + this->irelative_count_; // The first three entries in the GOT are reserved, and are written // by Output_data_got_plt_s390::do_write. @@ -1590,22 +1662,43 @@ Target_s390<size>::got_section(Symbol_table* symtab, Layout* layout) { gold_assert(symtab != NULL && layout != NULL); - // When using -z now, we can treat .got as a relro section. - // Without -z now, it is modified after program startup by lazy - // PLT relocations. - bool is_got_relro = parameters->options().now(); - Output_section_order got_order = (is_got_relro - ? ORDER_RELRO_LAST - : ORDER_DATA); + bool is_got_relro, is_got_plt_relro; + Output_section_order got_order, got_plt_order; + const char *got_plt_name; + if (parameters->options().relro()) + { + // Partial GOT relro. + is_got_relro = true; + is_got_plt_relro = false; + got_order = ORDER_RELRO_LAST; + got_plt_order = ORDER_NON_RELRO_FIRST; + got_plt_name = ".got.plt"; + } + else if (parameters->options().now()) + { + // When using -z now, we can treat the whole .got as a relro section. + is_got_plt_relro = is_got_relro = true; + got_order = got_plt_order = ORDER_RELRO_LAST; + got_plt_name = ".got"; + } + else + { + // Without -z now, it is modified after program startup by lazy + // PLT relocations. + is_got_plt_relro = is_got_relro = false; + got_order = got_plt_order = ORDER_DATA; + got_plt_name = ".got"; + } // The old GNU linker creates a .got.plt section. We just // create another set of data in the .got section. Note that we // always create a PLT if we create a GOT, although the PLT // might be empty. this->got_plt_ = new Output_data_got_plt_s390<size>(layout); - layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + layout->add_output_section_data(got_plt_name, elfcpp::SHT_PROGBITS, (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), - this->got_plt_, got_order, is_got_relro); + this->got_plt_, got_plt_order, + is_got_plt_relro); // The first three entries are reserved. this->got_plt_->set_current_data_size(3 * size / 8); @@ -1613,10 +1706,23 @@ Target_s390<size>::got_section(Symbol_table* symtab, Layout* layout) // If there are any IRELATIVE relocations, they get GOT entries // in .got.plt after the jump slot entries. this->got_irelative_ = new Output_data_space(size / 8, "** GOT IRELATIVE PLT"); - layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + layout->add_output_section_data(got_plt_name, elfcpp::SHT_PROGBITS, (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), this->got_irelative_, - got_order, is_got_relro); + got_plt_order, is_got_plt_relro); + + if (parameters->options().relro()) + { + // For partial relro, we need a _DYNAMIC pointer at + // _GLOBAL_OFFSET_TABLE_, not at DT_GOTPLT. + this->got_dynamic_ = new Output_data_got_dynamic_s390<size>(layout); + layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), + this->got_dynamic_, got_order, true); + this->got_dynamic_->set_current_data_size(size / 8); + } + else + this->got_dynamic_ = this->got_plt_; // Unlike some targets (.e.g x86), S/390 does not use separate .got and // .got.plt sections in output. The output .got section contains both @@ -1629,9 +1735,9 @@ Target_s390<size>::got_section(Symbol_table* symtab, Layout* layout) // Define _GLOBAL_OFFSET_TABLE_ at the start of the GOT. this->global_offset_table_ = - symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, + symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, Symbol_table::PREDEFINED, - this->got_plt_, + this->got_dynamic_, 0, 0, elfcpp::STT_OBJECT, elfcpp::STB_LOCAL, elfcpp::STV_HIDDEN, 0, @@ -1693,7 +1799,7 @@ Output_data_got_plt_s390<size>::do_write(Output_file* of) // The first entry in the GOT is the address of the .dynamic section // aka the PT_DYNAMIC segment. The next two entries are reserved. // We saved space for them when we created the section in - // Target_x86_64::got_section. + // Target_s390::got_section. const off_t got_file_offset = this->offset(); gold_assert(this->data_size() >= 3 * size / 8); unsigned char* const got_view = @@ -1705,6 +1811,24 @@ Output_data_got_plt_s390<size>::do_write(Output_file* of) of->write_output_view(got_file_offset, 3 * size / 8, got_view); } +// Write the first reserved word of the .got section. + +template<int size> +void +Output_data_got_dynamic_s390<size>::do_write(Output_file* of) +{ + // The first entry in the GOT is the address of the .dynamic section + // aka the PT_DYNAMIC segment. + const off_t got_file_offset = this->offset(); + gold_assert(this->data_size() == size / 8); + unsigned char* const got_view = + of->get_output_view(got_file_offset, size / 8); + Output_section* dynamic = this->layout_->dynamic_section(); + uint64_t dynamic_addr = dynamic == NULL ? 0 : dynamic->address(); + elfcpp::Swap<size, true>::writeval(got_view, dynamic_addr); + of->write_output_view(got_file_offset, size / 8, got_view); +} + // Create the PLT section. template<int size> @@ -1722,7 +1846,8 @@ Target_s390<size>::make_plt_section(Symbol_table* symtab, Layout* layout) this->rela_dyn_section(layout); this->plt_ = new Output_data_plt_s390<size>(layout, - this->got_, this->got_plt_, this->got_irelative_); + this->got_, this->got_plt_, this->got_irelative_, + this->got_dynamic_); // Add unwind information if requested. if (parameters->options().ld_generated_unwind_info()) @@ -1814,34 +1939,72 @@ Target_s390<size>::init_got_plt_for_update(Symbol_table* symtab, { gold_assert(this->got_ == NULL); + bool is_got_relro, is_got_plt_relro; + Output_section_order got_order, got_plt_order; + const char *got_plt_name; + if (parameters->options().relro()) + { + // Partial GOT relro. + is_got_relro = true; + is_got_plt_relro = false; + got_order = ORDER_RELRO_LAST; + got_plt_order = ORDER_NON_RELRO_FIRST; + got_plt_name = ".got.plt"; + } + else if (parameters->options().now()) + { + // When using -z now, we can treat the whole .got as a relro section. + is_got_plt_relro = is_got_relro = true; + got_order = got_plt_order = ORDER_RELRO_LAST; + got_plt_name = ".got"; + } + else + { + // Without -z now, it is modified after program startup by lazy + // PLT relocations. + is_got_plt_relro = is_got_relro = false; + got_order = got_plt_order = ORDER_DATA; + got_plt_name = ".got"; + } + // Add the three reserved entries. this->got_plt_ = new Output_data_got_plt_s390<size>(layout, (plt_count + 3) * size / 8); - layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, - (elfcpp::SHF_ALLOC - | elfcpp::SHF_WRITE), - this->got_plt_, ORDER_NON_RELRO_FIRST, - false); + layout->add_output_section_data(got_plt_name, elfcpp::SHT_PROGBITS, + (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), + this->got_plt_, got_plt_order, + is_got_plt_relro); // If there are any IRELATIVE relocations, they get GOT entries in // .got.plt after the jump slot entries. this->got_irelative_ = new Output_data_space(0, size / 8, "** GOT IRELATIVE PLT"); - layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + layout->add_output_section_data(got_plt_name, elfcpp::SHT_PROGBITS, elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE, this->got_irelative_, - ORDER_NON_RELRO_FIRST, false); + got_plt_order, is_got_plt_relro); + + if (parameters->options().relro()) + { + // For partial relro, we need a _DYNAMIC pointer at + // _GLOBAL_OFFSET_TABLE_, not at DT_GOTPLT. + this->got_dynamic_ = new Output_data_got_dynamic_s390<size>(layout); + layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, + (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), + this->got_dynamic_, got_order, true); + this->got_dynamic_->set_current_data_size(size / 8); + } + else + this->got_dynamic_ = this->got_plt_; this->got_ = new Output_data_got<size, true>(got_count * size / 8); layout->add_output_section_data(".got", elfcpp::SHT_PROGBITS, - (elfcpp::SHF_ALLOC - | elfcpp::SHF_WRITE), - this->got_, ORDER_RELRO_LAST, - true); + (elfcpp::SHF_ALLOC | elfcpp::SHF_WRITE), + this->got_, got_order, is_got_relro); // Define _GLOBAL_OFFSET_TABLE_ at the start of the PLT. this->global_offset_table_ = symtab->define_in_output_data("_GLOBAL_OFFSET_TABLE_", NULL, Symbol_table::PREDEFINED, - this->got_plt_, + this->got_dynamic_, 0, 0, elfcpp::STT_OBJECT, elfcpp::STB_LOCAL, elfcpp::STV_HIDDEN, 0, @@ -1849,7 +2012,8 @@ Target_s390<size>::init_got_plt_for_update(Symbol_table* symtab, // Create the PLT section. this->plt_ = new Output_data_plt_s390<size>(layout, - this->got_, this->got_plt_, this->got_irelative_, plt_count); + this->got_, this->got_plt_, this->got_irelative_, + this->got_dynamic_, plt_count); // Add unwind information if requested. if (parameters->options().ld_generated_unwind_info()) @@ -4045,12 +4209,25 @@ Target_s390<size>::do_finalize_sections( if (this->copy_relocs_.any_saved_relocs()) this->copy_relocs_.emit(this->rela_dyn_section(layout)); + Output_section* dynamic = layout->dynamic_section(); + if (this->got_plt_ != this->got_dynamic_ && dynamic != NULL && + parameters->options().output_is_position_independent()) + { + Reloc_section* rela_dyn = rela_dyn_section(layout); + rela_dyn->add_output_section_relative(dynamic, elfcpp::R_390_RELATIVE, + this->got_dynamic_, 0, 0); + } + // Set the size of the _GLOBAL_OFFSET_TABLE_ symbol to the size of // the .got section. Symbol* sym = this->global_offset_table_; if (sym != NULL) { uint64_t data_size = this->got_->current_data_size(); + data_size += this->got_plt_->current_data_size(); + data_size += this->got_irelative_->current_data_size(); + if (this->got_plt_ != this->got_dynamic_) + data_size += this->got_dynamic_->current_data_size(); symtab->get_sized_symbol<size>(sym)->set_symsize(data_size); } |