diff options
Diffstat (limited to 'gold/script-sections.cc')
| -rw-r--r-- | gold/script-sections.cc | 128 |
1 files changed, 120 insertions, 8 deletions
diff --git a/gold/script-sections.cc b/gold/script-sections.cc index 13c9771..990a1a2 100644 --- a/gold/script-sections.cc +++ b/gold/script-sections.cc @@ -54,6 +54,11 @@ class Sections_element virtual ~Sections_element() { } + // Record that an output section is relro. + virtual void + set_is_relro() + { } + // Create any required output sections. The only real // implementation is in Output_section_definition. virtual void @@ -80,7 +85,7 @@ class Sections_element // Return whether to place an orphan output section after this // element. virtual bool - place_orphan_here(const Output_section *, bool*) const + place_orphan_here(const Output_section *, bool*, bool*) const { return false; } // Set section addresses. This includes applying assignments if the @@ -126,6 +131,11 @@ class Sections_element uint64_t*) const { return false; } + // Return the associated Output_section if there is one. + virtual Output_section* + get_output_section() const + { return NULL; } + // Print the element for debugging purposes. virtual void print(FILE* f) const = 0; @@ -1231,6 +1241,11 @@ class Output_section_definition : public Sections_element void add_input_section(const Input_section_spec* spec, bool keep); + // Record that the output section is relro. + void + set_is_relro() + { this->is_relro_ = true; } + // Create any required output sections. void create_sections(Layout*); @@ -1251,7 +1266,7 @@ class Output_section_definition : public Sections_element // Return whether to place an orphan section after this one. bool - place_orphan_here(const Output_section *os, bool* exact) const; + place_orphan_here(const Output_section *os, bool* exact, bool*) const; // Set the section address. void @@ -1284,6 +1299,11 @@ class Output_section_definition : public Sections_element get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*, uint64_t*) const; + // Return the associated Output_section if there is one. + Output_section* + get_output_section() const + { return this->output_section_; } + // Print the contents to the FILE. This is for debugging. void print(FILE*) const; @@ -1319,6 +1339,8 @@ class Output_section_definition : public Sections_element uint64_t evaluated_load_address_; // The alignment after it has been evaluated. uint64_t evaluated_addralign_; + // The output section is relro. + bool is_relro_; }; // Constructor. @@ -1336,7 +1358,11 @@ Output_section_definition::Output_section_definition( fill_(NULL), phdrs_(NULL), elements_(), - output_section_(NULL) + output_section_(NULL), + evaluated_address_(0), + evaluated_load_address_(0), + evaluated_addralign_(0), + is_relro_(false) { } @@ -1517,8 +1543,11 @@ Output_section_definition::output_section_name(const char* file_name, bool Output_section_definition::place_orphan_here(const Output_section *os, - bool* exact) const + bool* exact, + bool* is_relro) const { + *is_relro = this->is_relro_; + // Check for the simple case first. if (this->output_section_ != NULL && this->output_section_->type() == os->type() @@ -1754,6 +1783,14 @@ Output_section_definition::set_section_addresses(Symbol_table* symtab, else *load_address = (this->output_section_->load_address() + (*dot_value - start_address)); + + if (this->output_section_ != NULL) + { + if (this->is_relro_) + this->output_section_->set_is_relro(); + else + this->output_section_->clear_is_relro(); + } } // Check a constraint (ONLY_IF_RO, etc.) on an output section. If @@ -1835,6 +1872,11 @@ Output_section_definition::alternate_constraint( this->output_section_ = posd->output_section_; posd->output_section_ = NULL; + if (this->is_relro_) + this->output_section_->set_is_relro(); + else + this->output_section_->clear_is_relro(); + return true; } @@ -1968,7 +2010,7 @@ class Orphan_output_section : public Sections_element // Return whether to place an orphan section after this one. bool - place_orphan_here(const Output_section *os, bool* exact) const; + place_orphan_here(const Output_section *os, bool* exact, bool*) const; // Set section addresses. void @@ -1979,6 +2021,11 @@ class Orphan_output_section : public Sections_element Output_section* allocate_to_segment(String_list**, bool*); + // Return the associated Output_section. + Output_section* + get_output_section() const + { return this->os_; } + // Print for debugging. void print(FILE* f) const @@ -1995,12 +2042,14 @@ class Orphan_output_section : public Sections_element bool Orphan_output_section::place_orphan_here(const Output_section* os, - bool* exact) const + bool* exact, + bool* is_relro) const { if (this->os_->type() == os->type() && this->os_->flags() == os->flags()) { *exact = true; + *is_relro = this->os_->is_relro(); return true; } return false; @@ -2206,7 +2255,9 @@ Script_sections::Script_sections() in_sections_clause_(false), sections_elements_(NULL), output_section_(NULL), - phdrs_elements_(NULL) + phdrs_elements_(NULL), + data_segment_align_index_(-1U), + saw_relro_end_(false) { } @@ -2334,6 +2385,39 @@ Script_sections::add_input_section(const Input_section_spec* spec, bool keep) this->output_section_->add_input_section(spec, keep); } +// This is called when we see DATA_SEGMENT_ALIGN. It means that any +// subsequent output sections may be relro. + +void +Script_sections::data_segment_align() +{ + if (this->data_segment_align_index_ != -1U) + gold_error(_("DATA_SEGMENT_ALIGN may only appear once in a linker script")); + this->data_segment_align_index_ = this->sections_elements_->size(); +} + +// This is called when we see DATA_SEGMENT_RELRO_END. It means that +// any output sections seen since DATA_SEGMENT_ALIGN are relro. + +void +Script_sections::data_segment_relro_end() +{ + if (this->saw_relro_end_) + gold_error(_("DATA_SEGMENT_RELRO_END may only appear once " + "in a linker script")); + this->saw_relro_end_ = true; + + if (this->data_segment_align_index_ == -1U) + gold_error(_("DATA_SEGMENT_RELRO_END must follow DATA_SEGMENT_ALIGN")); + else + { + for (size_t i = this->data_segment_align_index_; + i < this->sections_elements_->size(); + ++i) + (*this->sections_elements_)[i]->set_is_relro(); + } +} + // Create any required sections. void @@ -2418,15 +2502,18 @@ Script_sections::place_orphan(Output_section* os) { // Look for an output section definition which matches the output // section. Put a marker after that section. + bool is_relro = false; Sections_elements::iterator place = this->sections_elements_->end(); for (Sections_elements::iterator p = this->sections_elements_->begin(); p != this->sections_elements_->end(); ++p) { bool exact = false; - if ((*p)->place_orphan_here(os, &exact)) + bool is_relro_here; + if ((*p)->place_orphan_here(os, &exact, &is_relro_here)) { place = p; + is_relro = is_relro_here; if (exact) break; } @@ -2437,6 +2524,11 @@ Script_sections::place_orphan(Output_section* os) ++place; this->sections_elements_->insert(place, new Orphan_output_section(os)); + + if (is_relro) + os->set_is_relro(); + else + os->clear_is_relro(); } // Set the addresses of all the output sections. Walk through all the @@ -2479,6 +2571,26 @@ Script_sections::set_section_addresses(Symbol_table* symtab, Layout* layout) } } + // Force the alignment of the first TLS section to be the maximum + // alignment of all TLS sections. + Output_section* first_tls = NULL; + uint64_t tls_align = 0; + for (Sections_elements::const_iterator p = this->sections_elements_->begin(); + p != this->sections_elements_->end(); + ++p) + { + Output_section *os = (*p)->get_output_section(); + if (os != NULL && (os->flags() & elfcpp::SHF_TLS) != 0) + { + if (first_tls == NULL) + first_tls = os; + if (os->addralign() > tls_align) + tls_align = os->addralign(); + } + } + if (first_tls != NULL) + first_tls->set_addralign(tls_align); + // For a relocatable link, we implicitly set dot to zero. uint64_t dot_value = 0; uint64_t load_address = 0; |