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
+ create_sections(Layout*)
+ { }
+
// Add any symbol being defined to the symbol table.
virtual void
add_symbols_to_table(Symbol_table*)
// 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
// Get the list of segments to use for an allocated section when
// using a PHDRS clause. If this is an allocated section, return
- // the Output_section, and set *PHDRS_LIST to the list of PHDRS to
- // which it should be attached. If the PHDRS were not specified,
- // don't change *PHDRS_LIST.
+ // the Output_section, and set *PHDRS_LIST (the first parameter) to
+ // the list of PHDRS to which it should be attached. If the PHDRS
+ // were not specified, don't change *PHDRS_LIST. When not returning
+ // NULL, set *ORPHAN (the second parameter) according to whether
+ // this is an orphan section--one that is not mentioned in the
+ // linker script.
+ virtual Output_section*
+ allocate_to_segment(String_list**, bool*)
+ { return NULL; }
+
+ // Look for an output section by name and return the address, the
+ // load address, the alignment, and the size. This is used when an
+ // expression refers to an output section which was not actually
+ // created. This returns true if the section was found, false
+ // otherwise. The only real definition is for
+ // Output_section_definition.
+ virtual bool
+ get_output_section_info(const char*, uint64_t*, uint64_t*, uint64_t*,
+ uint64_t*) const
+ { return false; }
+
+ // Return the associated Output_section if there is one.
virtual Output_section*
- allocate_to_segment(String_list**)
+ get_output_section() const
{ return NULL; }
// Print the element for debugging purposes.
// output section definition the dot symbol is always considered
// to be absolute.
Output_section* dummy;
- *dot_value = this->val_->eval_with_dot(symtab, layout, *dot_value,
+ *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value,
NULL, &dummy);
}
uint64_t* dot_value, uint64_t* load_address)
{
Output_section* dummy;
- *dot_value = this->val_->eval_with_dot(symtab, layout, *dot_value,
+ *dot_value = this->val_->eval_with_dot(symtab, layout, false, *dot_value,
NULL, &dummy);
*load_address = *dot_value;
}
virtual ~Output_section_element()
{ }
+ // Return whether this element requires an output section to exist.
+ virtual bool
+ needs_output_section() const
+ { return false; }
+
// Add any symbol being defined to the symbol table.
virtual void
add_symbols_to_table(Symbol_table*)
finalize_symbols(Symbol_table* symtab, const Layout* layout,
uint64_t* dot_value, Output_section** dot_section)
{
- *dot_value = this->val_->eval_with_dot(symtab, layout, *dot_value,
+ *dot_value = this->val_->eval_with_dot(symtab, layout, true, *dot_value,
*dot_section, dot_section);
}
std::string* fill,
Input_section_list*)
{
- uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, *dot_value,
- *dot_section, dot_section);
+ uint64_t next_dot = this->val_->eval_with_dot(symtab, layout, false,
+ *dot_value, *dot_section,
+ dot_section);
if (next_dot < *dot_value)
gold_error(_("dot may not move backward"));
if (next_dot > *dot_value && output_section != NULL)
- *dot_value);
Output_section_data* posd;
if (fill->empty())
- posd = new Output_data_fixed_space(length, 0);
+ posd = new Output_data_zero_fill(length, 0);
else
{
std::string this_fill = this->get_fill_string(fill, length);
void
do_write_to_buffer(unsigned char*);
+ // Write to a map file.
+ void
+ do_print_to_mapfile(Mapfile* mapfile) const
+ { mapfile->print_output_data(this, _("** expression")); }
+
private:
template<bool big_endian>
void
{
Output_section* dummy;
uint64_t val = this->val_->eval_with_dot(this->symtab_, this->layout_,
- this->dot_value_,
+ true, this->dot_value_,
this->dot_section_, &dummy);
if (parameters->target().is_big_endian())
: size_(size), is_signed_(is_signed), val_(val)
{ }
+ // If there is a data item, then we must create an output section.
+ bool
+ needs_output_section() const
+ { return true; }
+
// Finalize symbols--we just need to update dot.
void
finalize_symbols(Symbol_table*, const Layout*, uint64_t* dot_value,
std::string* fill, Input_section_list*)
{
Output_section* fill_section;
- uint64_t fill_val = this->val_->eval_with_dot(symtab, layout,
+ uint64_t fill_val = this->val_->eval_with_dot(symtab, layout, false,
*dot_value, *dot_section,
&fill_section);
if (fill_section != NULL)
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*);
+
// Add any symbols being defined to the symbol table.
void
add_symbols_to_table(Symbol_table* symtab);
// 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
alternate_constraint(Output_section_definition*, Section_constraint);
// Get the list of segments to use for an allocated section when
- // using a PHDRS clause. If this is an allocated section, return
- // the Output_section, and set *PHDRS_LIST to the list of PHDRS to
- // which it should be attached. If the PHDRS were not specified,
- // don't change *PHDRS_LIST.
+ // using a PHDRS clause.
+ Output_section*
+ allocate_to_segment(String_list** phdrs_list, bool* orphan);
+
+ // Look for an output section by name and return the address, the
+ // load address, the alignment, and the size. This is used when an
+ // expression refers to an output section which was not actually
+ // created. This returns true if the section was found, false
+ // otherwise.
+ bool
+ 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*
- allocate_to_segment(String_list** phdrs_list);
+ get_output_section() const
+ { return this->output_section_; }
// Print the contents to the FILE. This is for debugging.
void
// The Output_section created for this definition. This will be
// NULL if none was created.
Output_section* output_section_;
+ // The address after it has been evaluated.
+ uint64_t evaluated_address_;
+ // The load address after it has been evaluated.
+ 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.
fill_(NULL),
phdrs_(NULL),
elements_(),
- output_section_(NULL)
+ output_section_(NULL),
+ evaluated_address_(0),
+ evaluated_load_address_(0),
+ evaluated_addralign_(0),
+ is_relro_(false)
{
}
this->elements_.push_back(p);
}
+// Create any required output sections. We need an output section if
+// there is a data statement here.
+
+void
+Output_section_definition::create_sections(Layout* layout)
+{
+ if (this->output_section_ != NULL)
+ return;
+ for (Output_section_elements::const_iterator p = this->elements_.begin();
+ p != this->elements_.end();
+ ++p)
+ {
+ if ((*p)->needs_output_section())
+ {
+ const char* name = this->name_.c_str();
+ this->output_section_ = layout->make_output_section_for_script(name);
+ return;
+ }
+ }
+}
+
// Add any symbols being defined to the symbol table.
void
if (this->address_ != NULL)
{
Output_section* dummy;
- address = this->address_->eval_with_dot(symtab, layout,
+ address = this->address_->eval_with_dot(symtab, layout, true,
*dot_value, NULL,
&dummy);
}
if (this->align_ != NULL)
{
Output_section* dummy;
- uint64_t align = this->align_->eval_with_dot(symtab, layout,
+ uint64_t align = this->align_->eval_with_dot(symtab, layout, true,
*dot_value,
NULL,
&dummy);
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()
else
{
Output_section* dummy;
- address = this->address_->eval_with_dot(symtab, layout, *dot_value,
- NULL, &dummy);
+ address = this->address_->eval_with_dot(symtab, layout, true,
+ *dot_value, NULL, &dummy);
}
uint64_t align;
else
{
Output_section* align_section;
- align = this->align_->eval_with_dot(symtab, layout, *dot_value,
+ align = this->align_->eval_with_dot(symtab, layout, true, *dot_value,
NULL, &align_section);
if (align_section != NULL)
gold_warning(_("alignment of section %s is not absolute"),
&& (this->output_section_->flags() & elfcpp::SHF_ALLOC) != 0)
this->output_section_->set_address(address);
- if (this->load_address_ != NULL && this->output_section_ != NULL)
+ this->evaluated_address_ = address;
+ this->evaluated_addralign_ = align;
+
+ if (this->load_address_ == NULL)
+ this->evaluated_load_address_ = address;
+ else
{
Output_section* dummy;
uint64_t load_address =
- this->load_address_->eval_with_dot(symtab, layout, *dot_value,
+ this->load_address_->eval_with_dot(symtab, layout, true, *dot_value,
this->output_section_, &dummy);
- this->output_section_->set_load_address(load_address);
+ if (this->output_section_ != NULL)
+ this->output_section_->set_load_address(load_address);
+ this->evaluated_load_address_ = load_address;
}
uint64_t subalign;
else
{
Output_section* subalign_section;
- subalign = this->subalign_->eval_with_dot(symtab, layout, *dot_value,
- NULL, &subalign_section);
+ subalign = this->subalign_->eval_with_dot(symtab, layout, true,
+ *dot_value, NULL,
+ &subalign_section);
if (subalign_section != NULL)
gold_warning(_("subalign of section %s is not absolute"),
this->name_.c_str());
// FIXME: The GNU linker supports fill values of arbitrary
// length.
Output_section* fill_section;
- uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout,
+ uint64_t fill_val = this->fill_->eval_with_dot(symtab, layout, true,
*dot_value,
NULL,
&fill_section);
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
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;
}
// Get the list of segments to use for an allocated section when using
-// a PHDRS clause. If this is an allocated section, return the
-// Output_section, and set *PHDRS_LIST to the list of PHDRS to which
-// it should be attached. If the PHDRS were not specified, don't
-// change *PHDRS_LIST.
+// a PHDRS clause.
Output_section*
-Output_section_definition::allocate_to_segment(String_list** phdrs_list)
+Output_section_definition::allocate_to_segment(String_list** phdrs_list,
+ bool* orphan)
{
if (this->output_section_ == NULL)
return NULL;
if ((this->output_section_->flags() & elfcpp::SHF_ALLOC) == 0)
return NULL;
+ *orphan = false;
if (this->phdrs_ != NULL)
*phdrs_list = this->phdrs_;
return this->output_section_;
}
+// Look for an output section by name and return the address, the load
+// address, the alignment, and the size. This is used when an
+// expression refers to an output section which was not actually
+// created. This returns true if the section was found, false
+// otherwise.
+
+bool
+Output_section_definition::get_output_section_info(const char* name,
+ uint64_t* address,
+ uint64_t* load_address,
+ uint64_t* addralign,
+ uint64_t* size) const
+{
+ if (this->name_ != name)
+ return false;
+
+ if (this->output_section_ != NULL)
+ {
+ *address = this->output_section_->address();
+ if (this->output_section_->has_load_address())
+ *load_address = this->output_section_->load_address();
+ else
+ *load_address = *address;
+ *addralign = this->output_section_->addralign();
+ *size = this->output_section_->current_data_size();
+ }
+ else
+ {
+ *address = this->evaluated_address_;
+ *load_address = this->evaluated_load_address_;
+ *addralign = this->evaluated_addralign_;
+ *size = 0;
+ }
+
+ return true;
+}
+
// Print for debugging.
void
// 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
set_section_addresses(Symbol_table*, Layout*, uint64_t*, uint64_t*);
// Get the list of segments to use for an allocated section when
- // using a PHDRS clause. If this is an allocated section, return
- // the Output_section.
+ // using a PHDRS clause.
Output_section*
- allocate_to_segment(String_list**);
+ allocate_to_segment(String_list**, bool*);
+
+ // Return the associated Output_section.
+ Output_section*
+ get_output_section() const
+ { return this->os_; }
// Print for debugging.
void
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;
// Output_section. We don't change the list of segments.
Output_section*
-Orphan_output_section::allocate_to_segment(String_list**)
+Orphan_output_section::allocate_to_segment(String_list**, bool* orphan)
{
if ((this->os_->flags() & elfcpp::SHF_ALLOC) == 0)
return NULL;
+ *orphan = true;
return this->os_;
}
eval_load_address(Symbol_table* symtab, Layout* layout)
{
if (this->load_address_ != NULL)
- this->load_address_value_ = this->load_address_->eval(symtab, layout);
+ this->load_address_value_ = this->load_address_->eval(symtab, layout,
+ true);
}
// Return the load address.
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)
{
}
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
+Script_sections::create_sections(Layout* layout)
+{
+ if (!this->saw_sections_clause_)
+ return;
+ for (Sections_elements::iterator p = this->sections_elements_->begin();
+ p != this->sections_elements_->end();
+ ++p)
+ (*p)->create_sections(layout);
+}
+
// Add any symbols we are defining to the symbol table.
void
{
// 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;
- if ((*p)->place_orphan_here(os, &exact))
+ bool exact = false;
+ bool is_relro_here;
+ if ((*p)->place_orphan_here(os, &exact, &is_relro_here))
{
place = p;
+ is_relro = is_relro_here;
if (exact)
break;
}
++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
}
}
+ // 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;
need_new_segment = true;
}
else if (is_current_seg_readonly
- && ((*p)->flags() & elfcpp::SHF_WRITE) != 0)
+ && ((*p)->flags() & elfcpp::SHF_WRITE) != 0
+ && !parameters->options().omagic())
{
// Don't put a writable section in the same segment as a
// non-writable section.
// efficient in any case. We try to use the first PT_LOAD segment
// if we can, otherwise we make a new one.
+ if (first_seg == NULL)
+ return NULL;
+
size_t sizeof_headers = this->total_header_size(layout);
- if (first_seg != NULL
- && (first_seg->paddr() & (abi_pagesize - 1)) >= sizeof_headers)
+ uint64_t vma = first_seg->vaddr();
+ uint64_t lma = first_seg->paddr();
+
+ uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers);
+
+ if ((lma & (abi_pagesize - 1)) >= sizeof_headers)
{
- first_seg->set_addresses(first_seg->vaddr() - sizeof_headers,
- first_seg->paddr() - sizeof_headers);
+ first_seg->set_addresses(vma - subtract, lma - subtract);
return first_seg;
}
+ // If there is no room to squeeze in the headers, then punt. The
+ // resulting executable probably won't run on GNU/Linux, but we
+ // trust that the user knows what they are doing.
+ if (lma < subtract || vma < subtract)
+ return NULL;
+
Output_segment* load_seg = layout->make_output_segment(elfcpp::PT_LOAD,
elfcpp::PF_R);
- if (first_seg == NULL)
- load_seg->set_addresses(0, 0);
- else
- {
- uint64_t vma = first_seg->vaddr();
- uint64_t lma = first_seg->paddr();
-
- uint64_t subtract = this->header_size_adjustment(lma, sizeof_headers);
- if (lma >= subtract && vma >= subtract)
- load_seg->set_addresses(vma - subtract, lma - subtract);
- else
- {
- // We could handle this case by create the file header
- // outside of any PT_LOAD segment, and creating a new
- // PT_LOAD segment after the others to hold the segment
- // headers.
- gold_error(_("sections loaded on first page without room for "
- "file and program headers are not supported"));
- }
- }
+ load_seg->set_addresses(vma - subtract, lma - subtract);
return load_seg;
}
p != this->sections_elements_->end();
++p)
{
- Output_section* os = (*p)->allocate_to_segment(&phdr_names);
+ bool orphan;
+ Output_section* os = (*p)->allocate_to_segment(&phdr_names, &orphan);
if (os == NULL)
continue;
continue;
}
+ // If this is an orphan section--one that was not explicitly
+ // mentioned in the linker script--then it should not inherit
+ // any segment type other than PT_LOAD. Otherwise, e.g., the
+ // PT_INTERP segment will pick up following orphan sections,
+ // which does not make sense. If this is not an orphan section,
+ // we trust the linker script.
+ if (orphan)
+ {
+ String_list::iterator q = phdr_names->begin();
+ while (q != phdr_names->end())
+ {
+ Name_to_segment::const_iterator r = name_to_segment.find(*q);
+ // We give errors about unknown segments below.
+ if (r == name_to_segment.end()
+ || r->second->type() == elfcpp::PT_LOAD)
+ ++q;
+ else
+ q = phdr_names->erase(q);
+ }
+ }
+
bool in_load_segment = false;
for (String_list::const_iterator q = phdr_names->begin();
q != phdr_names->end();
}
}
+// Look for an output section by name and return the address, the load
+// address, the alignment, and the size. This is used when an
+// expression refers to an output section which was not actually
+// created. This returns true if the section was found, false
+// otherwise.
+
+bool
+Script_sections::get_output_section_info(const char* name, uint64_t* address,
+ uint64_t* load_address,
+ uint64_t* addralign,
+ uint64_t* size) const
+{
+ if (!this->saw_sections_clause_)
+ return false;
+ for (Sections_elements::const_iterator p = this->sections_elements_->begin();
+ p != this->sections_elements_->end();
+ ++p)
+ if ((*p)->get_output_section_info(name, address, load_address, addralign,
+ size))
+ return true;
+ return false;
+}
+
// Print the SECTIONS clause to F for debugging.
void