* options.h (class General_options): Add -z relro.

	* layout.cc (Layout::Layout): Initialize relro_segment_.
	(Layout::add_output_section_data): Return the output section.
	(Layout::make_output_section): Rcognize relro sections and mark
	them appropriately.
	(Layout::attach_allocated_section_to_segment): Put relro sections
	in a PT_GNU_RELRO segment.
	(Layout::create_initial_dynamic_sections): Mark the .dynamic
	section as relro.
	(Layout::segment_precedes): Sort PT_GNU_RELRO segments after
	PT_TLS segments.
	(Layout::linkonce_mapping): Map d.rel.ro.local to
	.data.rel.ro.local.
	(Layout::output_section_name): Us .data.rel.ro.local for any
	section which begins with that.
	* layout.h (class Layout): Update add_output_section_data
	declaration.  Add relro_segment_ field.
	* output.cc (Output_section::Output_section): Initialize is_relro_
	and is_relro_local_ fields.
	(Output_segment::add_output_section): Group relro sections.
	(Output_segment::is_first_section_relro): New function.
	(Output_segment::maximum_alignment): If there is a relro section,
	align the segment to the common page size.
	(Output_segment::set_section_addresses): Track whether we are
	looking at relro sections.  If the last section is a relro
	section, align to the common page size.
	(Output_segment::set_section_list_addresses): Add in_relro
	parameter.  Change all callers.  Align to the page size when
	moving from relro to non-relro section.
	(Output_segment::set_offset): Align memsz of a PT_GNU_RELRO
	segment.
	* output.h (class Output_section): Add is_relro_ and
	is_relro_local_ fields.
	(Output_section::is_relro): New function.
	(Output_section::set_is_relro): New function.
	(Output_section::is_relro_local): New function.
	(Output_section::set_is_relro_local): New function.
	(class Output_segment): Update declarations.
	* i386.cc (Target_i386::got_section): Mark .got section as relro.
	* sparc.cc (Target_sparc::got_section): Likewise.
	* x86_64.cc (Target_x86_64::got_section): Likewise.
	* testsuite/relro_test_main.cc: New file.
	* testsuite/relro_test.cc: New file.
	* testsuite/Makefile.am (check_PROGRAMS): Add relro_test.
	(relro_test_SOURCES, relro_test_DEPENDENCIES): New variables.
	(relro_test_LDFLAGS, relro_test_LDADD): New variables.
	(relro_test.so, relro_test_pic.o): New targets.
	* testsuite/Makefile.in: Rebuild.

4 files changed, 181 insertions, 7 deletions

diff --git a/gold/testsuite/Makefile.am b/gold/testsuite/Makefile.am
index 75c9c92..ab9294e 100644
--- a/gold/testsuite/Makefile.am
+++ b/gold/testsuite/Makefile.am
@@ -782,6 +782,16 @@ protected_2_DEPENDENCIES = gcctestdir/ld protected_1.so
 protected_2_LDFLAGS = -Bgcctestdir/ -Wl,-R,.
 protected_2_LDADD = protected_1.so
 
+check_PROGRAMS += relro_test
+relro_test_SOURCES = relro_test_main.cc
+relro_test_DEPENDENCIES = gcctestdir/ld relro_test.so
+relro_test_LDFLAGS = -Bgcctestdir/ -Wl,-R,.
+relro_test_LDADD = relro_test.so
+relro_test.so: gcctestdir/ld relro_test_pic.o
+	$(CXXLINK) -Bgcctestdir/ -shared -Wl,-z,relro relro_test_pic.o
+relro_test_pic.o: relro_test.cc
+	$(CXXCOMPILE) -c -fpic -o $@ $<
+
 check_PROGRAMS += script_test_1
 script_test_1_SOURCES = script_test_1.cc
 script_test_1_DEPENDENCIES = gcctestdir/ld script_test_1.t
diff --git a/gold/testsuite/Makefile.in b/gold/testsuite/Makefile.in
index 5231c98..931d043 100644
--- a/gold/testsuite/Makefile.in
+++ b/gold/testsuite/Makefile.in
@@ -228,9 +228,9 @@ check_PROGRAMS = object_unittest$(EXEEXT) binary_unittest$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@am__append_19 = ver_test ver_test_2 \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_6 ver_test_8 \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	protected_1 protected_2 \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_1 script_test_2 \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	justsyms binary_test \
-@GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_3
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	relro_test script_test_1 \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_2 justsyms \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	binary_test script_test_3
 @GCC_FALSE@script_test_1_DEPENDENCIES = libgoldtest.a ../libgold.a \
 @GCC_FALSE@	../../libiberty/libiberty.a $(am__DEPENDENCIES_1) \
 @GCC_FALSE@	$(am__DEPENDENCIES_1)
@@ -346,6 +346,7 @@ libgoldtest_a_OBJECTS = $(am_libgoldtest_a_OBJECTS)
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	ver_test_8$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	protected_1$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	protected_2$(EXEEXT) \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	relro_test$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_1$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_2$(EXEEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	justsyms$(EXEEXT) \
@@ -514,6 +515,10 @@ am__protected_2_SOURCES_DIST = protected_main_1.cc protected_3.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	protected_main_1.$(OBJEXT) \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	protected_3.$(OBJEXT)
 protected_2_OBJECTS = $(am_protected_2_OBJECTS)
+am__relro_test_SOURCES_DIST = relro_test_main.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@am_relro_test_OBJECTS =  \
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	relro_test_main.$(OBJEXT)
+relro_test_OBJECTS = $(am_relro_test_OBJECTS)
 am__script_test_1_SOURCES_DIST = script_test_1.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@am_script_test_1_OBJECTS =  \
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	script_test_1.$(OBJEXT)
@@ -760,9 +765,9 @@ SOURCES = $(libgoldtest_a_SOURCES) basic_pic_test.c \
 	$(initpri1_SOURCES) $(justsyms_SOURCES) many_sections_r_test.c \
 	$(many_sections_test_SOURCES) $(object_unittest_SOURCES) \
 	$(protected_1_SOURCES) $(protected_2_SOURCES) \
-	$(script_test_1_SOURCES) $(script_test_2_SOURCES) \
-	script_test_3.c $(tls_pic_test_SOURCES) \
-	$(tls_shared_gd_to_ie_test_SOURCES) \
+	$(relro_test_SOURCES) $(script_test_1_SOURCES) \
+	$(script_test_2_SOURCES) script_test_3.c \
+	$(tls_pic_test_SOURCES) $(tls_shared_gd_to_ie_test_SOURCES) \
 	$(tls_shared_gnu2_gd_to_ie_test_SOURCES) \
 	$(tls_shared_gnu2_test_SOURCES) $(tls_shared_ie_test_SOURCES) \
 	$(tls_shared_nonpic_test_SOURCES) $(tls_shared_test_SOURCES) \
@@ -808,7 +813,7 @@ DIST_SOURCES = $(libgoldtest_a_SOURCES) basic_pic_test.c \
 	$(am__initpri1_SOURCES_DIST) $(am__justsyms_SOURCES_DIST) \
 	many_sections_r_test.c $(am__many_sections_test_SOURCES_DIST) \
 	$(object_unittest_SOURCES) $(am__protected_1_SOURCES_DIST) \
-	$(am__protected_2_SOURCES_DIST) \
+	$(am__protected_2_SOURCES_DIST) $(am__relro_test_SOURCES_DIST) \
 	$(am__script_test_1_SOURCES_DIST) \
 	$(am__script_test_2_SOURCES_DIST) script_test_3.c \
 	$(am__tls_pic_test_SOURCES_DIST) \
@@ -1304,6 +1309,10 @@ binary_unittest_SOURCES = binary_unittest.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@protected_2_DEPENDENCIES = gcctestdir/ld protected_1.so
 @GCC_TRUE@@NATIVE_LINKER_TRUE@protected_2_LDFLAGS = -Bgcctestdir/ -Wl,-R,.
 @GCC_TRUE@@NATIVE_LINKER_TRUE@protected_2_LDADD = protected_1.so
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test_SOURCES = relro_test_main.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test_DEPENDENCIES = gcctestdir/ld relro_test.so
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test_LDFLAGS = -Bgcctestdir/ -Wl,-R,.
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test_LDADD = relro_test.so
 @GCC_TRUE@@NATIVE_LINKER_TRUE@script_test_1_SOURCES = script_test_1.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@script_test_1_DEPENDENCIES = gcctestdir/ld script_test_1.t
 @GCC_TRUE@@NATIVE_LINKER_TRUE@script_test_1_LDFLAGS = -Bgcctestdir/ -Wl,-R,. -T $(srcdir)/script_test_1.t
@@ -1468,6 +1477,9 @@ protected_1$(EXEEXT): $(protected_1_OBJECTS) $(protected_1_DEPENDENCIES)
 protected_2$(EXEEXT): $(protected_2_OBJECTS) $(protected_2_DEPENDENCIES) 
 	@rm -f protected_2$(EXEEXT)
 	$(CXXLINK) $(protected_2_LDFLAGS) $(protected_2_OBJECTS) $(protected_2_LDADD) $(LIBS)
+relro_test$(EXEEXT): $(relro_test_OBJECTS) $(relro_test_DEPENDENCIES) 
+	@rm -f relro_test$(EXEEXT)
+	$(CXXLINK) $(relro_test_LDFLAGS) $(relro_test_OBJECTS) $(relro_test_LDADD) $(LIBS)
 script_test_1$(EXEEXT): $(script_test_1_OBJECTS) $(script_test_1_DEPENDENCIES) 
 	@rm -f script_test_1$(EXEEXT)
 	$(CXXLINK) $(script_test_1_LDFLAGS) $(script_test_1_OBJECTS) $(script_test_1_LDADD) $(LIBS)
@@ -1627,6 +1639,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/protected_main_1.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/protected_main_2.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/protected_main_3.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/relro_test_main.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/script_test_1.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/script_test_2.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/script_test_2a.Po@am__quote@
@@ -2191,6 +2204,10 @@ uninstall-am: uninstall-info-am
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -c -fpic -o $@ $<
 @GCC_TRUE@@NATIVE_LINKER_TRUE@protected_3_pic.o: protected_3.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -c -fpic -o $@ $<
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test.so: gcctestdir/ld relro_test_pic.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXLINK) -Bgcctestdir/ -shared -Wl,-z,relro relro_test_pic.o
+@GCC_TRUE@@NATIVE_LINKER_TRUE@relro_test_pic.o: relro_test.cc
+@GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -c -fpic -o $@ $<
 @GCC_TRUE@@NATIVE_LINKER_TRUE@justsyms_2.o: justsyms_2.cc
 @GCC_TRUE@@NATIVE_LINKER_TRUE@	$(CXXCOMPILE) -c -o $@ $<
 @GCC_TRUE@@NATIVE_LINKER_TRUE@justsyms_2r.o: justsyms_2.o gcctestdir/ld $(srcdir)/justsyms.t
diff --git a/gold/testsuite/relro_test.cc b/gold/testsuite/relro_test.cc
new file mode 100644
index 0000000..d1bd9dd
--- /dev/null
+++ b/gold/testsuite/relro_test.cc
@@ -0,0 +1,114 @@
+// relro_test.cc -- test -z relro for gold
+
+// Copyright 2008 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+#include <cassert>
+#include <csignal>
+#include <stdint.h>
+#include <unistd.h>
+
+// This code is put into a shared library linked with -z relro.
+
+// i1 and i2 are not relro variables.
+int i1 = 1;
+static int i2 = 2;
+
+// P1 is a global relro variable.
+int* const p1 = &i1;
+
+// P2 is a local relro variable.
+int* const p2 = &i2;
+
+// Test symbol addresses.
+
+bool
+t1()
+{
+  void* i1addr = static_cast<void*>(&i1);
+  void* i2addr = static_cast<void*>(&i2);
+  const void* p1addr = static_cast<const void*>(&p1);
+  const void* p2addr = static_cast<const void*>(&p2);
+
+  // The relro variables should precede the non-relro variables in the
+  // memory image.
+  assert(i1addr > p1addr);
+  assert(i1addr > p2addr);
+  assert(i2addr > p1addr);
+  assert(i2addr > p2addr);
+
+  // The relro variables should not be on the same page as the
+  // non-relro variables.
+  const size_t page_size = getpagesize();
+  uintptr_t i1page = reinterpret_cast<uintptr_t>(i1addr) & ~ (page_size - 1);
+  uintptr_t i2page = reinterpret_cast<uintptr_t>(i2addr) & ~ (page_size - 1);
+  uintptr_t p1page = reinterpret_cast<uintptr_t>(p1addr) & ~ (page_size - 1);
+  uintptr_t p2page = reinterpret_cast<uintptr_t>(p2addr) & ~ (page_size - 1);
+  assert(i1page != p1page);
+  assert(i1page != p2page);
+  assert(i2page != p1page);
+  assert(i2page != p2page);
+
+  return true;
+}
+
+// A signal handler for SIGSEGV.
+
+extern "C"
+void
+sigsegv_handler(int)
+{
+  throw 0;
+}
+
+// Use a separate function to throw the exception, so that we don't
+// need to use -fnon-call-exceptions.
+
+void f2() __attribute__ ((noinline));
+void
+f2()
+{
+  int** pp1 = const_cast<int**>(&p1);
+  *pp1 = &i2;
+
+  // We shouldn't get here--the assignment to *pp1 should write to
+  // memory which the dynamic linker marked as read-only, giving us a
+  // SIGSEGV, causing sigsegv_handler to be invoked, to throw past us.
+  assert(0);
+}
+
+// Changing a relro variable should give us a SIGSEGV.
+
+bool
+t2()
+{
+  signal(SIGSEGV, sigsegv_handler);
+
+  try
+    {
+      f2();
+      return false;
+    }
+  catch (int i)
+    {
+      assert(i == 0);
+      return true;
+    }
+}
diff --git a/gold/testsuite/relro_test_main.cc b/gold/testsuite/relro_test_main.cc
new file mode 100644
index 0000000..6f5ea2b
--- /dev/null
+++ b/gold/testsuite/relro_test_main.cc
@@ -0,0 +1,33 @@
+// relro_test_main.cc -- test -z relro for gold, main function
+
+// Copyright 2008 Free Software Foundation, Inc.
+// Written by Ian Lance Taylor <iant@google.com>.
+
+// This file is part of gold.
+
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program; if not, write to the Free Software
+// Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
+// MA 02110-1301, USA.
+
+#include <cassert>
+
+extern bool t1();
+extern bool t2();
+
+int
+main()
+{
+  assert(t1());
+  assert(t2());
+}