Don't make dynamic .data.rel.ro SEC_READONLY

I'd made this dynamic section read-only so a flag test distinguished
it from .dynbss, but like any other .data.rel.ro section it really
should be marked read-write.  (It is read-only after relocation, not
before.)  When using the standard linker scripts this usually doesn't
matter since the output section is among other read-write sections and
not page aligned.  However, it might matter in the extraordinary case
of the dynamic section being the only .data.rel.ro section with the
output section just happening to be page aligned and a multiple of a
page in size.  In that case the output section would be read-only, and
live it its own read-only PT_LOAD segment, which is incorrect.

	* elflink.c (_bfd_elf_create_dynamic_sections): Don't make
	dynamic .data.rel.ro read-only.
	* elf32-arm.c (elf32_arm_finish_dynamic_symbol): Compare section
	rather than section flags when deciding where copy reloc goes.
	* elf32-cris.c (elf_cris_finish_dynamic_symbol): Likewise.
	* elf32-hppa.c (elf32_hppa_finish_dynamic_symbol): Likewise.
	* elf32-i386.c (elf_i386_finish_dynamic_symbol): Likewise.
	* elf32-metag.c (elf_metag_finish_dynamic_symbol): Likewise.
	* elf32-microblaze.c (microblaze_elf_finish_dynamic_symbol): Likewise.
	* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol): Likewise.
	* elf32-or1k.c (or1k_elf_finish_dynamic_symbol): Likewise.
	* elf32-ppc.c (ppc_elf_finish_dynamic_symbol): Likewise.
	* elf32-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
	* elf32-tic6x.c (elf32_tic6x_finish_dynamic_symbol): Likewise.
	* elf32-tilepro.c (tilepro_elf_finish_dynamic_symbol): Likewise.
	* elf64-ppc.c (ppc64_elf_finish_dynamic_symbol): Likewise.
	* elf64-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
	* elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Likewise.
	* elfnn-aarch64.c (elfNN_aarch64_finish_dynamic_symbol): Likewise.
	* elfnn-riscv.c (riscv_elf_finish_dynamic_symbol): Likewise.
	* elfxx-mips.c (_bfd_mips_vxworks_finish_dynamic_symbol): Likewise.
	* elfxx-sparc.c (_bfd_sparc_elf_finish_dynamic_symbol): Likewise.
	* elfxx-tilegx.c (tilegx_elf_finish_dynamic_symbol): Likewise.

bfd/ChangeLog

@@ -1,3 +1,29 @@
+2017-02-28  Alan Modra  <amodra@gmail.com>
+
+	* elflink.c (_bfd_elf_create_dynamic_sections): Don't make
+	dynamic .data.rel.ro read-only.
+	* elf32-arm.c (elf32_arm_finish_dynamic_symbol): Compare section
+	rather than section flags when deciding where copy reloc goes.
+	* elf32-cris.c (elf_cris_finish_dynamic_symbol): Likewise.
+	* elf32-hppa.c (elf32_hppa_finish_dynamic_symbol): Likewise.
+	* elf32-i386.c (elf_i386_finish_dynamic_symbol): Likewise.
+	* elf32-metag.c (elf_metag_finish_dynamic_symbol): Likewise.
+	* elf32-microblaze.c (microblaze_elf_finish_dynamic_symbol): Likewise.
+	* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol): Likewise.
+	* elf32-or1k.c (or1k_elf_finish_dynamic_symbol): Likewise.
+	* elf32-ppc.c (ppc_elf_finish_dynamic_symbol): Likewise.
+	* elf32-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
+	* elf32-tic6x.c (elf32_tic6x_finish_dynamic_symbol): Likewise.
+	* elf32-tilepro.c (tilepro_elf_finish_dynamic_symbol): Likewise.
+	* elf64-ppc.c (ppc64_elf_finish_dynamic_symbol): Likewise.
+	* elf64-s390.c (elf_s390_finish_dynamic_symbol): Likewise.
+	* elf64-x86-64.c (elf_x86_64_finish_dynamic_symbol): Likewise.
+	* elfnn-aarch64.c (elfNN_aarch64_finish_dynamic_symbol): Likewise.
+	* elfnn-riscv.c (riscv_elf_finish_dynamic_symbol): Likewise.
+	* elfxx-mips.c (_bfd_mips_vxworks_finish_dynamic_symbol): Likewise.
+	* elfxx-sparc.c (_bfd_sparc_elf_finish_dynamic_symbol): Likewise.
+	* elfxx-tilegx.c (tilegx_elf_finish_dynamic_symbol): Likewise.
+
 2017-02-28  Maciej W. Rozycki  <macro@imgtec.com>
 
 	* elfxx-mips.c (mips_elf_perform_relocation): Also handle the

bfd/elf32-arm.c

@@ -16311,7 +16311,7 @@ elf32_arm_finish_dynamic_symbol (bfd * output_bfd,
 		      + h->root.u.def.section->output_section->vma
 		      + h->root.u.def.section->output_offset);
       rel.r_info = ELF32_R_INFO (h->dynindx, R_ARM_COPY);
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	s = htab->root.sreldynrelro;
       else
 	s = htab->root.srelbss;

bfd/elf32-cris.c

@@ -2275,7 +2275,7 @@ elf_cris_finish_dynamic_symbol (bfd *output_bfd,
 		  && (h->root.type == bfd_link_hash_defined
 		      || h->root.type == bfd_link_hash_defweak));
 
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	s = htab->root.sreldynrelro;
       else
 	s = htab->root.srelbss;

bfd/elf32-hppa.c

@@ -4432,7 +4432,7 @@ elf32_hppa_finish_dynamic_symbol (bfd *output_bfd,
 		      + eh->root.u.def.section->output_section->vma);
       rela.r_addend = 0;
       rela.r_info = ELF32_R_INFO (eh->dynindx, R_PARISC_COPY);
-      if ((eh->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (eh->root.u.def.section == htab->etab.sdynrelro)
 	sec = htab->etab.sreldynrelro;
       else
 	sec = htab->etab.srelbss;

bfd/elf32-i386.c

@@ -5666,7 +5666,7 @@ do_glob_dat:
 		      + h->root.u.def.section->output_section->vma
 		      + h->root.u.def.section->output_offset);
       rel.r_info = ELF32_R_INFO (h->dynindx, R_386_COPY);
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf32-metag.c

@@ -3229,7 +3229,7 @@ elf_metag_finish_dynamic_symbol (bfd *output_bfd,
 		      + eh->root.u.def.section->output_section->vma);
       rel.r_addend = 0;
       rel.r_info = ELF32_R_INFO (eh->dynindx, R_METAG_COPY);
-      if ((eh->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (eh->root.u.def.section == htab->etab.sdynrelro)
 	s = htab->etab.sreldynrelro;
       else
 	s = htab->etab.srelbss;

bfd/elf32-microblaze.c

@@ -3277,7 +3277,7 @@ microblaze_elf_finish_dynamic_symbol (bfd *output_bfd,
                        + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_MICROBLAZE_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf32-nios2.c

@@ -5280,7 +5280,7 @@ nios2_elf32_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_NIOS2_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	s = htab->root.sreldynrelro;
       else
 	s = htab->root.srelbss;

bfd/elf32-or1k.c

@@ -1949,7 +1949,7 @@ or1k_elf_finish_dynamic_symbol (bfd *output_bfd,
                        + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_OR1K_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	s = htab->root.sreldynrelro;
       else
 	s = htab->root.srelbss;

bfd/elf32-ppc.c

@@ -10355,7 +10355,7 @@ ppc_elf_finish_dynamic_symbol (bfd *output_bfd,
 
       if (ppc_elf_hash_entry (h)->has_sda_refs)
 	s = htab->relsbss;
-      else if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      else if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf32-s390.c

@@ -3827,7 +3827,7 @@ elf_s390_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_390_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf32-tic6x.c

@@ -1876,7 +1876,7 @@ elf32_tic6x_finish_dynamic_symbol (bfd * output_bfd,
 		      + h->root.u.def.section->output_offset);
       rel.r_info = ELF32_R_INFO (h->dynindx, R_C6000_COPY);
       rel.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf32-tilepro.c

@@ -3813,7 +3813,7 @@ tilepro_elf_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_TILEPRO_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf64-ppc.c

@@ -15477,7 +15477,7 @@ ppc64_elf_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELF64_R_INFO (h->dynindx, R_PPC64_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	srel = htab->elf.sreldynrelro;
       else
 	srel = htab->elf.srelbss;

bfd/elf64-s390.c

@@ -3623,7 +3623,7 @@ elf_s390_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELF64_R_INFO (h->dynindx, R_390_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elf64-x86-64.c

@@ -6189,7 +6189,7 @@ do_glob_dat:
 		       + h->root.u.def.section->output_offset);
       rela.r_info = htab->r_info (h->dynindx, R_X86_64_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elflink.c

@@ -424,7 +424,7 @@ _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
 	 initialize them at run time.  The linker script puts the .dynbss
 	 section into the .bss section of the final image.  */
       s = bfd_make_section_anyway_with_flags (abfd, ".dynbss",
-					      (SEC_ALLOC | SEC_LINKER_CREATED));
+					      SEC_ALLOC | SEC_LINKER_CREATED);
       if (s == NULL)
 	return FALSE;
       htab->sdynbss = s;
@@ -432,11 +432,10 @@ _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
       if (bed->want_dynrelro)
 	{
 	  /* Similarly, but for symbols that were originally in read-only
-	     sections.  */
+	     sections.  This section doesn't really need to have contents,
+	     but make it like other .data.rel.ro sections.  */
 	  s = bfd_make_section_anyway_with_flags (abfd, ".data.rel.ro",
-						  (SEC_ALLOC | SEC_READONLY
+						  flags);
-						   | SEC_HAS_CONTENTS
-						   | SEC_LINKER_CREATED));
 	  if (s == NULL)
 	    return FALSE;
 	  htab->sdynrelro = s;

bfd/elfnn-aarch64.c

@@ -8988,7 +8988,7 @@ do_glob_dat:
 		       + h->root.u.def.section->output_offset);
       rela.r_info = ELFNN_R_INFO (h->dynindx, AARCH64_R (COPY));
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	s = htab->root.sreldynrelro;
       else
 	s = htab->root.srelbss;

bfd/elfnn-riscv.c

@@ -2412,7 +2412,7 @@ riscv_elf_finish_dynamic_symbol (bfd *output_bfd,
       rela.r_offset = sec_addr (h->root.u.def.section) + h->root.u.def.value;
       rela.r_info = ELFNN_R_INFO (h->dynindx, R_RISCV_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elfxx-mips.c

@@ -11173,7 +11173,7 @@ _bfd_mips_vxworks_finish_dynamic_symbol (bfd *output_bfd,
 		      + h->root.u.def.value);
       rel.r_info = ELF32_R_INFO (h->dynindx, R_MIPS_COPY);
       rel.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->root.sdynrelro)
 	srel = htab->root.sreldynrelro;
       else
 	srel = htab->root.srelbss;

bfd/elfxx-sparc.c

@@ -4568,7 +4568,7 @@ _bfd_sparc_elf_finish_dynamic_symbol (bfd *output_bfd,
 		       + h->root.u.def.section->output_offset);
       rela.r_info = SPARC_ELF_R_INFO (htab, NULL, h->dynindx, R_SPARC_COPY);
       rela.r_addend = 0;
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;

bfd/elfxx-tilegx.c

@@ -4198,7 +4198,7 @@ tilegx_elf_finish_dynamic_symbol (bfd *output_bfd,
       /* This symbols needs a copy reloc.  Set it up.  */
       BFD_ASSERT (h->dynindx != -1);
 
-      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+      if (h->root.u.def.section == htab->elf.sdynrelro)
 	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;