dynrelro section for read-only dynamic symbols copied into executable

Variables defined in shared libraries are copied into an executable's
.bss section when code in the executable is non-PIC and thus would
require dynamic text relocations to access the variable directly in
the shared library.  Recent x86 toolchains also copy variables into
the executable to gain a small speed improvement.

The problem is that if the variable was originally read-only, the copy
in .bss is writable, potentially opening a security hole.  This patch
cures that problem by putting the copy in a section that becomes
read-only after ld.so relocation, provided -z relro is in force.

The patch also fixes a microblaze linker segfault on attempting to
use dynamic bss variables.

bfd/
	PR ld/20995
	* elf-bfd.h (struct elf_link_hash_table): Add sdynrelro and
	sreldynrelro.
	(struct elf_backend_data): Add want_dynrelro.
	* elfxx-target.h (elf_backend_want_dynrelro): Define.
	(elfNN_bed): Update initializer.
	* elflink.c (_bfd_elf_create_dynamic_sections): Create
	sdynrelro and sreldynrelro sections.
	* elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Place variables
	copied into the executable from read-only sections into sdynrelro.
	(elf32_arm_size_dynamic_sections): Handle sdynrelro.
	(elf32_arm_finish_dynamic_symbol): Select sreldynrelro for
	dynamic relocs in sdynrelro.
	(elf_backend_want_dynrelro): Define.
	* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol)
	(elf32_hppa_size_dynamic_sections, elf32_hppa_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-i386.c (elf_i386_adjust_dynamic_symbol)
	(elf_i386_size_dynamic_sections, elf_i386_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-metag.c (elf_metag_adjust_dynamic_symbol)
	(elf_metag_size_dynamic_sections, elf_metag_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol)
	(microblaze_elf_size_dynamic_sections)
	(microblaze_elf_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol)
	(nios2_elf32_adjust_dynamic_symbol)
	(nios2_elf32_size_dynamic_sections)
	(elf_backend_want_dynrelro): As above.
	* elf32-or1k.c (or1k_elf_finish_dynamic_symbol)
	(or1k_elf_adjust_dynamic_symbol, or1k_elf_size_dynamic_sections)
	(elf_backend_want_dynrelro): As above.
	* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol)
	(ppc_elf_size_dynamic_sections, ppc_elf_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-s390.c (elf_s390_adjust_dynamic_symbol)
	(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol)
	(elf32_tic6x_size_dynamic_sections)
	(elf32_tic6x_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf32-tilepro.c (tilepro_elf_adjust_dynamic_symbol)
	(tilepro_elf_size_dynamic_sections)
	(tilepro_elf_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol)
	(ppc64_elf_size_dynamic_sections, ppc64_elf_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf64-s390.c (elf_s390_adjust_dynamic_symbol)
	(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elf64-x86-64.c (elf_x86_64_adjust_dynamic_symbol)
	(elf_x86_64_size_dynamic_sections)
	(elf_x86_64_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol)
	(elfNN_aarch64_size_dynamic_sections)
	(elfNN_aarch64_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol)
	(riscv_elf_size_dynamic_sections, riscv_elf_finish_dynamic_symbol)
	(elf_backend_want_dynrelro): As above.
	* elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol)
	(_bfd_mips_elf_size_dynamic_sections)
	(_bfd_mips_vxworks_finish_dynamic_symbol): As above.
	* elfxx-sparc.c (_bfd_sparc_elf_adjust_dynamic_symbol)
	(_bfd_sparc_elf_size_dynamic_sections)
	(_bfd_sparc_elf_finish_dynamic_symbol): As above.
	* elfxx-tilegx.c (tilegx_elf_adjust_dynamic_symbol)
	(tilegx_elf_size_dynamic_sections)
	(tilegx_elf_finish_dynamic_symbol): As above.
	* elf32-mips.c (elf_backend_want_dynrelro): Define.
	* elf64-mips.c (elf_backend_want_dynrelro): Define.
	* elf32-sparc.c (elf_backend_want_dynrelro): Define.
	* elf64-sparc.c (elf_backend_want_dynrelro): Define.
	* elf32-tilegx.c (elf_backend_want_dynrelro): Define.
	* elf64-tilegx.c (elf_backend_want_dynrelro): Define.
	* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Tidy.
	(microblaze_elf_size_dynamic_sections): Handle sdynbss.
	* elf32-nios2.c (nios2_elf32_size_dynamic_sections): Make use
	of linker shortcuts to dynamic sections rather than comparing
	names.  Correctly set "got" flag.
ld/
	PR ld/20995
	* testsuite/ld-arm/farcall-mixed-app-v5.d: Update to suit changed
	stub hash table traversal caused by section id increment.  Accept
	the previous output too.
	* testsuite/ld-arm/farcall-mixed-app.d: Likewise.
	* testsuite/ld-arm/farcall-mixed-lib-v4t.d: Likewise.
	* testsuite/ld-arm/farcall-mixed-lib.d: Likewise.
	* testsuite/ld-elf/pr20995a.s, * testsuite/ld-elf/pr20995b.s,
	* testsuite/ld-elf/pr20995.r: New test.
	* testsuite/ld-elf/elf.exp: Run it.

bfd/ChangeLog

@@ -1,3 +1,91 @@
+2016-12-26  Alan Modra  <amodra@gmail.com>
+
+	PR ld/20995
+	* elf-bfd.h (struct elf_link_hash_table): Add sdynrelro and
+	sreldynrelro.
+	(struct elf_backend_data): Add want_dynrelro.
+	* elfxx-target.h (elf_backend_want_dynrelro): Define.
+	(elfNN_bed): Update initializer.
+	* elflink.c (_bfd_elf_create_dynamic_sections): Create
+	sdynrelro and sreldynrelro sections.
+	* elf32-arm.c (elf32_arm_adjust_dynamic_symbol): Place variables
+	copied into the executable from read-only sections into sdynrelro.
+	(elf32_arm_size_dynamic_sections): Handle sdynrelro.
+	(elf32_arm_finish_dynamic_symbol): Select sreldynrelro for
+	dynamic relocs in sdynrelro.
+	(elf_backend_want_dynrelro): Define.
+	* elf32-hppa.c (elf32_hppa_adjust_dynamic_symbol)
+	(elf32_hppa_size_dynamic_sections, elf32_hppa_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-i386.c (elf_i386_adjust_dynamic_symbol)
+	(elf_i386_size_dynamic_sections, elf_i386_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-metag.c (elf_metag_adjust_dynamic_symbol)
+	(elf_metag_size_dynamic_sections, elf_metag_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol)
+	(microblaze_elf_size_dynamic_sections)
+	(microblaze_elf_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-nios2.c (nios2_elf32_finish_dynamic_symbol)
+	(nios2_elf32_adjust_dynamic_symbol)
+	(nios2_elf32_size_dynamic_sections)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-or1k.c (or1k_elf_finish_dynamic_symbol)
+	(or1k_elf_adjust_dynamic_symbol, or1k_elf_size_dynamic_sections)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-ppc.c (ppc_elf_adjust_dynamic_symbol)
+	(ppc_elf_size_dynamic_sections, ppc_elf_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-s390.c (elf_s390_adjust_dynamic_symbol)
+	(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-tic6x.c (elf32_tic6x_adjust_dynamic_symbol)
+	(elf32_tic6x_size_dynamic_sections)
+	(elf32_tic6x_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf32-tilepro.c (tilepro_elf_adjust_dynamic_symbol)
+	(tilepro_elf_size_dynamic_sections)
+	(tilepro_elf_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf64-ppc.c (ppc64_elf_adjust_dynamic_symbol)
+	(ppc64_elf_size_dynamic_sections, ppc64_elf_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf64-s390.c (elf_s390_adjust_dynamic_symbol)
+	(elf_s390_size_dynamic_sections, elf_s390_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elf64-x86-64.c (elf_x86_64_adjust_dynamic_symbol)
+	(elf_x86_64_size_dynamic_sections)
+	(elf_x86_64_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elfnn-aarch64.c (elfNN_aarch64_adjust_dynamic_symbol)
+	(elfNN_aarch64_size_dynamic_sections)
+	(elfNN_aarch64_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elfnn-riscv.c (riscv_elf_adjust_dynamic_symbol)
+	(riscv_elf_size_dynamic_sections, riscv_elf_finish_dynamic_symbol)
+	(elf_backend_want_dynrelro): As above.
+	* elfxx-mips.c (_bfd_mips_elf_adjust_dynamic_symbol)
+	(_bfd_mips_elf_size_dynamic_sections)
+	(_bfd_mips_vxworks_finish_dynamic_symbol): As above.
+	* elfxx-sparc.c (_bfd_sparc_elf_adjust_dynamic_symbol)
+	(_bfd_sparc_elf_size_dynamic_sections)
+	(_bfd_sparc_elf_finish_dynamic_symbol): As above.
+	* elfxx-tilegx.c (tilegx_elf_adjust_dynamic_symbol)
+	(tilegx_elf_size_dynamic_sections)
+	(tilegx_elf_finish_dynamic_symbol): As above.
+	* elf32-mips.c (elf_backend_want_dynrelro): Define.
+	* elf64-mips.c (elf_backend_want_dynrelro): Define.
+	* elf32-sparc.c (elf_backend_want_dynrelro): Define.
+	* elf64-sparc.c (elf_backend_want_dynrelro): Define.
+	* elf32-tilegx.c (elf_backend_want_dynrelro): Define.
+	* elf64-tilegx.c (elf_backend_want_dynrelro): Define.
+	* elf32-microblaze.c (microblaze_elf_adjust_dynamic_symbol): Tidy.
+	(microblaze_elf_size_dynamic_sections): Handle sdynbss.
+	* elf32-nios2.c (nios2_elf32_size_dynamic_sections): Make use
+	of linker shortcuts to dynamic sections rather than comparing
+	names.  Correctly set "got" flag.
+
 2016-12-26  Alan Modra  <amodra@gmail.com>
 
 	* elf-bfd.h (struct elf_link_hash_table): Add sdynbss and srelbss.

bfd/elf-bfd.h

@@ -597,6 +597,8 @@ struct elf_link_hash_table
   asection *srelplt;
   asection *sdynbss;
   asection *srelbss;
+  asection *sdynrelro;
+  asection *sreldynrelro;
   asection *igotplt;
   asection *iplt;
   asection *irelplt;
@@ -1451,6 +1453,7 @@ struct elf_backend_data
   unsigned can_refcount : 1;
   unsigned want_got_sym : 1;
   unsigned want_dynbss : 1;
+  unsigned want_dynrelro : 1;
 
   /* Targets which do not support physical addressing often require
      that the p_paddr field in the section header to be set to zero.

bfd/elf32-arm.c

@@ -15264,7 +15264,7 @@ elf32_arm_adjust_dynamic_symbol (struct bfd_link_info * info,
 				 struct elf_link_hash_entry * h)
 {
   bfd * dynobj;
-  asection * s;
+  asection *s, *srel;
   struct elf32_arm_link_hash_entry * eh;
   struct elf32_arm_link_hash_table *globals;
 
@@ -15363,20 +15363,24 @@ elf32_arm_adjust_dynamic_symbol (struct bfd_link_info * info,
      determine the address it must put in the global offset table, so
      both the dynamic object and the regular object will refer to the
      same memory location for the variable.  */
-  s = globals->root.sdynbss;
-  BFD_ASSERT (s != NULL);
-
   /* If allowed, we must generate a R_ARM_COPY reloc to tell the dynamic
      linker to copy the initial value out of the dynamic object and into
      the runtime process image.  We need to remember the offset into the
      .rel(a).bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = globals->root.sdynrelro;
+      srel = globals->root.sreldynrelro;
+    }
+  else
+    {
+      s = globals->root.sdynbss;
+      srel = globals->root.srelbss;
+    }
   if (info->nocopyreloc == 0
       && (h->root.u.def.section->flags & SEC_ALLOC) != 0
       && h->size != 0)
     {
-      asection *srel;
-
-      srel = bfd_get_linker_section (dynobj, RELOC_SECTION (globals, ".bss"));
       elf32_arm_allocate_dynrelocs (info, srel, 1);
       h->needs_copy = 1;
     }
@@ -16091,7 +16095,8 @@ elf32_arm_size_dynamic_sections (bfd * output_bfd ATTRIBUTE_UNUSED,
 	       && s != htab->root.sgotplt
 	       && s != htab->root.iplt
 	       && s != htab->root.igotplt
-	       && s != htab->root.sdynbss)
+	       && s != htab->root.sdynbss
+	       && s != htab->root.sdynrelro)
 	{
 	  /* It's not one of our sections, so don't allocate space.  */
 	  continue;
@@ -16301,14 +16306,15 @@ elf32_arm_finish_dynamic_symbol (bfd * output_bfd,
 		  && (h->root.type == bfd_link_hash_defined
 		      || h->root.type == bfd_link_hash_defweak));
 
-      s = htab->root.srelbss;
-      BFD_ASSERT (s != NULL);
-
       rel.r_addend = 0;
       rel.r_offset = (h->root.u.def.value
 		      + 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)
+	s = htab->root.sreldynrelro;
+      else
+	s = htab->root.srelbss;
       elf32_arm_add_dynreloc (output_bfd, info, s, &rel);
     }
 
@@ -19389,6 +19395,7 @@ elf32_arm_backend_symbol_processing (bfd *abfd, asymbol *sym)
 #define elf_backend_plt_readonly       1
 #define elf_backend_want_got_plt       1
 #define elf_backend_want_plt_sym       0
+#define elf_backend_want_dynrelro      1
 #define elf_backend_may_use_rel_p      1
 #define elf_backend_may_use_rela_p     0
 #define elf_backend_default_use_rela_p 0

bfd/elf32-hppa.c

@@ -1793,7 +1793,7 @@ elf32_hppa_adjust_dynamic_symbol (struct bfd_link_info *info,
 				  struct elf_link_hash_entry *eh)
 {
   struct elf32_hppa_link_hash_table *htab;
-  asection *sec;
+  asection *sec, *srel;
 
   /* If this is a function, put it in the procedure linkage table.  We
      will fill in the contents of the procedure linkage table later.  */
@@ -1899,14 +1899,22 @@ elf32_hppa_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((eh->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      sec = htab->etab.sdynrelro;
+      srel = htab->etab.sreldynrelro;
+    }
+  else
+    {
+      sec = htab->etab.sdynbss;
+      srel = htab->etab.srelbss;
+    }
   if ((eh->root.u.def.section->flags & SEC_ALLOC) != 0 && eh->size != 0)
     {
-      htab->etab.srelbss->size += sizeof (Elf32_External_Rela);
+      srel->size += sizeof (Elf32_External_Rela);
       eh->needs_copy = 1;
     }
 
-  sec = htab->etab.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, eh, sec);
 }
 
@@ -2374,7 +2382,8 @@ elf32_hppa_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	    }
 	}
       else if (sec == htab->etab.sgot
-	       || sec == htab->etab.sdynbss)
+	       || sec == htab->etab.sdynbss
+	       || sec == htab->etab.sdynrelro)
 	;
       else if (CONST_STRNEQ (bfd_get_section_name (dynobj, sec), ".rela"))
 	{
@@ -4427,13 +4436,15 @@ elf32_hppa_finish_dynamic_symbol (bfd *output_bfd,
 		 || eh->root.type == bfd_link_hash_defweak)))
 	abort ();
 
-      sec = htab->etab.srelbss;
-
       rela.r_offset = (eh->root.u.def.value
 		      + eh->root.u.def.section->output_offset
 		      + 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)
+	sec = htab->etab.sreldynrelro;
+      else
+	sec = htab->etab.srelbss;
       loc = sec->contents + sec->reloc_count++ * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rela, loc);
     }
@@ -4641,6 +4652,7 @@ elf32_hppa_elf_get_symbol_type (Elf_Internal_Sym *elf_sym, int type)
 #define elf_backend_plt_readonly	     0
 #define elf_backend_want_plt_sym	     0
 #define elf_backend_got_header_size	     8
+#define elf_backend_want_dynrelro	     1
 #define elf_backend_rela_normal		     1
 #define elf_backend_dtrel_excludes_plt	     1
 

bfd/elf32-i386.c

@@ -2424,7 +2424,7 @@ elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info,
 				struct elf_link_hash_entry *h)
 {
   struct elf_i386_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
   struct elf_i386_link_hash_entry *eh;
   struct elf_dyn_relocs *p;
 
@@ -2584,14 +2584,22 @@ elf_i386_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_386_COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf32_External_Rel);
+      srel->size += sizeof (Elf32_External_Rel);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -3405,7 +3413,8 @@ elf_i386_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
 	       || s == htab->elf.igotplt
 	       || s == htab->plt_got
 	       || s == htab->plt_eh_frame
-	       || s == htab->elf.sdynbss)
+	       || s == htab->elf.sdynbss
+	       || s == htab->elf.sdynrelro)
 	{
 	  /* Strip these too.  */
 	}
@@ -5564,20 +5573,26 @@ do_glob_dat:
   if (h->needs_copy)
     {
       Elf_Internal_Rela rel;
+      asection *s;
 
       /* This symbol needs a copy reloc.  Set it up.  */
 
       if (h->dynindx == -1
 	  || (h->root.type != bfd_link_hash_defined
 	      && h->root.type != bfd_link_hash_defweak)
-	  || htab->elf.srelbss == NULL)
+	  || htab->elf.srelbss == NULL
+	  || htab->elf.sreldynrelro == NULL)
 	abort ();
 
       rel.r_offset = (h->root.u.def.value
 		      + 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);
-      elf_append_rel (output_bfd, htab->elf.srelbss, &rel);
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
+      elf_append_rel (output_bfd, s, &rel);
     }
 
   return TRUE;
@@ -6028,6 +6043,7 @@ elf_i386_hash_symbol (struct elf_link_hash_entry *h)
 #define elf_backend_dtrel_excludes_plt	1
 #define elf_backend_extern_protected_data 1
 #define elf_backend_caches_rawsize	1
+#define elf_backend_want_dynrelro	1
 
 /* Support RELA for objdump of prelink objects.  */
 #define elf_info_to_howto		      elf_i386_info_to_howto_rel

bfd/elf32-metag.c

@@ -2470,7 +2470,7 @@ elf_metag_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct elf_metag_link_hash_table *htab;
   struct elf_metag_link_hash_entry *hh;
   struct elf_metag_dyn_reloc_entry *hdh_p;
-  asection *s;
+  asection *s, *srel;
 
   /* If this is a function, put it in the procedure linkage table.  We
      will fill in the contents of the procedure linkage table later,
@@ -2564,14 +2564,22 @@ elf_metag_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((eh->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->etab.sdynrelro;
+      srel = htab->etab.sreldynrelro;
+    }
+  else
+    {
+      s = htab->etab.sdynbss;
+      srel = htab->etab.srelbss;
+    }
   if ((eh->root.u.def.section->flags & SEC_ALLOC) != 0 && eh->size != 0)
     {
-      htab->etab.srelbss->size += sizeof (Elf32_External_Rela);
+      srel->size += sizeof (Elf32_External_Rela);
       eh->needs_copy = 1;
     }
 
-  s = htab->etab.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, eh, s);
 }
 
@@ -2933,7 +2941,8 @@ elf_metag_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
       if (s == htab->etab.splt
 	  || s == htab->etab.sgot
 	  || s == htab->etab.sgotplt
-	  || s == htab->etab.sdynbss)
+	  || s == htab->etab.sdynbss
+	  || s == htab->etab.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -3215,13 +3224,15 @@ elf_metag_finish_dynamic_symbol (bfd *output_bfd,
 		 || eh->root.type == bfd_link_hash_defweak)))
 	abort ();
 
-      s = htab->etab.srelbss;
-
       rel.r_offset = (eh->root.u.def.value
 		      + eh->root.u.def.section->output_offset
 		      + 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)
+	s = htab->etab.sreldynrelro;
+      else
+	s = htab->etab.srelbss;
       loc = s->contents + s->reloc_count++ * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rel, loc);
     }
@@ -4286,6 +4297,7 @@ elf_metag_plt_sym_val (bfd_vma i, const asection *plt,
 #define elf_backend_want_plt_sym		0
 #define elf_backend_plt_readonly		1
 #define elf_backend_dtrel_excludes_plt		1
+#define elf_backend_want_dynrelro		1
 
 #define bfd_elf32_bfd_reloc_type_lookup	metag_reloc_type_lookup
 #define bfd_elf32_bfd_reloc_name_lookup	metag_reloc_name_lookup

bfd/elf32-microblaze.c

@@ -2557,9 +2557,8 @@ microblaze_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct elf32_mb_link_hash_table *htab;
   struct elf32_mb_link_hash_entry * eh;
   struct elf32_mb_dyn_relocs *p;
-  asection *sdynbss, *s;
+  asection *s, *srel;
   unsigned int power_of_two;
-  bfd *dynobj;
 
   htab = elf32_mb_hash_table (info);
   if (htab == NULL)
@@ -2658,11 +2657,19 @@ microblaze_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_MICROBLAZE_COPY reloc to tell the dynamic linker
      to copy the initial value out of the dynamic object and into the
      runtime process image.  */
-  dynobj = elf_hash_table (info)->dynobj;
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-  BFD_ASSERT (dynobj != NULL);
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf32_External_Rela);
+      srel->size += sizeof (Elf32_External_Rela);
       h->needs_copy = 1;
     }
 
@@ -2672,21 +2679,20 @@ microblaze_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   if (power_of_two > 3)
     power_of_two = 3;
 
-  sdynbss = htab->elf.sdynbss;
   /* Apply the required alignment.  */
-  sdynbss->size = BFD_ALIGN (sdynbss->size, (bfd_size_type) (1 << power_of_two));
+  s->size = BFD_ALIGN (s->size, (bfd_size_type) (1 << power_of_two));
-  if (power_of_two > bfd_get_section_alignment (dynobj, sdynbss))
+  if (power_of_two > s->alignment_power)
     {
-      if (! bfd_set_section_alignment (dynobj, sdynbss, power_of_two))
+      if (!bfd_set_section_alignment (s->owner, s, power_of_two))
 	return FALSE;
     }
 
   /* Define the symbol as being at this point in the section.  */
-  h->root.u.def.section = sdynbss;
+  h->root.u.def.section = s;
-  h->root.u.def.value = sdynbss->size;
+  h->root.u.def.value = s->size;
 
   /* Increment the section size to make room for the symbol.  */
-  sdynbss->size += h->size;
+  s->size += h->size;
   return TRUE;
 }
 
@@ -3050,7 +3056,9 @@ microblaze_elf_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
         }
       else if (s != htab->elf.splt
 	       && s != htab->elf.sgot
-	       && s != htab->elf.sgotplt)
+	       && s != htab->elf.sgotplt
+	       && s != htab->elf.sdynbss
+	       && s != htab->elf.sdynrelro)
         {
           /* It's not one of our sections, so don't allocate space.  */
           continue;
@@ -3256,14 +3264,15 @@ microblaze_elf_finish_dynamic_symbol (bfd *output_bfd,
 
       BFD_ASSERT (h->dynindx != -1);
 
-      s = bfd_get_linker_section (htab->elf.dynobj, ".rela.bss");
-      BFD_ASSERT (s != NULL);
-
       rela.r_offset = (h->root.u.def.value
                        + h->root.u.def.section->output_section->vma
                        + 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)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
       loc = s->contents + s->reloc_count++ * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rela, loc);
     }
@@ -3439,6 +3448,7 @@ microblaze_elf_add_symbol_hook (bfd *abfd,
 #define elf_backend_want_got_plt    		1
 #define elf_backend_plt_readonly    		1
 #define elf_backend_got_header_size 		12
+#define elf_backend_want_dynrelro		1
 #define elf_backend_rela_normal     		1
 #define elf_backend_dtrel_excludes_plt		1
 

bfd/elf32-mips.c

@@ -2482,6 +2482,7 @@ static const struct ecoff_debug_swap mips_elf32_ecoff_debug_swap = {
 #define elf_backend_ecoff_debug_swap	&mips_elf32_ecoff_debug_swap
 
 #define elf_backend_got_header_size	(4 * MIPS_RESERVED_GOTNO)
+#define elf_backend_want_dynrelro	1
 #define elf_backend_may_use_rel_p	1
 #define elf_backend_may_use_rela_p	0
 #define elf_backend_default_use_rela_p	0

bfd/elf32-nios2.c

@@ -5275,14 +5275,16 @@ nios2_elf32_finish_dynamic_symbol (bfd *output_bfd,
 		  && (h->root.type == bfd_link_hash_defined
 		      || h->root.type == bfd_link_hash_defweak));
 
-      s = htab->root.srelbss;
-      BFD_ASSERT (s != NULL);
-
       rela.r_offset = (h->root.u.def.value
 		       + h->root.u.def.section->output_section->vma
 		       + 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)
+	s = htab->root.sreldynrelro;
+      else
+	s = htab->root.srelbss;
+      BFD_ASSERT (s != NULL);
       loc = s->contents + s->reloc_count++ * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rela, loc);
     }
@@ -5441,7 +5443,7 @@ nios2_elf32_adjust_dynamic_symbol (struct bfd_link_info *info,
 {
   struct elf32_nios2_link_hash_table *htab;
   bfd *dynobj;
-  asection *s;
+  asection *s, *srel;
   unsigned align2;
 
   htab = elf32_nios2_hash_table (info);
@@ -5523,19 +5525,22 @@ nios2_elf32_adjust_dynamic_symbol (struct bfd_link_info *info,
      determine the address it must put in the global offset table, so
      both the dynamic object and the regular object will refer to the
      same memory location for the variable.  */
-  s = htab->root.sdynbss;
-  BFD_ASSERT (s != NULL);
-
   /* We must generate a R_NIOS2_COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rela.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->root.sdynrelro;
+      srel = htab->root.sreldynrelro;
+    }
+  else
+    {
+      s = htab->root.sdynbss;
+      srel = htab->root.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
     {
-      asection *srel;
-
-      srel = htab->root.srelbss;
-      BFD_ASSERT (srel != NULL);
       srel->size += sizeof (Elf32_External_Rela);
       h->needs_copy = 1;
     }
@@ -5975,7 +5980,7 @@ nios2_elf32_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	 of the dynobj section names depend upon the input files.  */
       name = bfd_get_section_name (dynobj, s);
 
-      if (strcmp (name, ".plt") == 0)
+      if (s == htab->root.splt)
 	{
 	  /* Remember whether there is a PLT.  */
 	  plt = s->size != 0;
@@ -5998,9 +6003,14 @@ nios2_elf32_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	      s->reloc_count = 0;
 	    }
 	}
-      else if (CONST_STRNEQ (name, ".got"))
+      else if (s == htab->root.sgot
-	got = s->size != 0;
+	       || s == htab->root.sgotplt)
-      else if (strcmp (name, ".dynbss") != 0)
+	{
+	  if (s->size != 0)
+	    got = TRUE;
+	}
+      else if (s != htab->root.sdynbss
+	       && s != htab->root.sdynrelro)
 	/* It's not one of our sections, so don't allocate space.  */
 	continue;
 
@@ -6249,6 +6259,7 @@ const struct bfd_elf_special_section elf32_nios2_special_sections[] =
 #define elf_backend_can_refcount	1
 #define elf_backend_plt_readonly	1
 #define elf_backend_want_got_plt	1
+#define elf_backend_want_dynrelro	1
 #define elf_backend_rela_normal		1
 #define elf_backend_dtrel_excludes_plt	1
 

bfd/elf32-or1k.c

@@ -1944,17 +1944,16 @@ or1k_elf_finish_dynamic_symbol (bfd *output_bfd,
                   && (h->root.type == bfd_link_hash_defined
                       || h->root.type == bfd_link_hash_defweak));
 
-      s = bfd_get_section_by_name (h->root.u.def.section->owner,
-                                   ".rela.bss");
-      BFD_ASSERT (s != NULL);
-
       rela.r_offset = (h->root.u.def.value
                        + h->root.u.def.section->output_section->vma
                        + h->root.u.def.section->output_offset);
       rela.r_info = ELF32_R_INFO (h->dynindx, R_OR1K_COPY);
       rela.r_addend = 0;
-      loc = s->contents;
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-      loc += s->reloc_count * sizeof (Elf32_External_Rela);
+	s = htab->root.sreldynrelro;
+      else
+	s = htab->root.srelbss;
+      loc = s->contents + s->reloc_count * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rela, loc);
       ++s->reloc_count;
     }
@@ -1995,7 +1994,7 @@ or1k_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct elf_or1k_link_hash_entry *eh;
   struct elf_or1k_dyn_relocs *p;
   bfd *dynobj;
-  asection *s;
+  asection *s, *srel;
 
   dynobj = elf_hash_table (info)->dynobj;
 
@@ -2098,19 +2097,22 @@ or1k_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   if (htab == NULL)
     return FALSE;
 
-  s = htab->root.sdynbss;
-  BFD_ASSERT (s != NULL);
-
   /* We must generate a R_OR1K_COPY reloc to tell the dynamic linker
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rela.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->root.sdynrelro;
+      srel = htab->root.sreldynrelro;
+    }
+  else
+    {
+      s = htab->root.sdynbss;
+      srel = htab->root.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      asection *srel;
-
-      srel = htab->root.srelbss;
-      BFD_ASSERT (srel != NULL);
       srel->size += sizeof (Elf32_External_Rela);
       h->needs_copy = 1;
     }
@@ -2472,7 +2474,8 @@ or1k_elf_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
       if (s == htab->root.splt
           || s == htab->root.sgot
           || s == htab->root.sgotplt
-          || s == htab->root.sdynbss)
+	  || s == htab->root.sdynbss
+	  || s == htab->root.sdynrelro)
         {
           /* Strip this section if we don't need it; see the
              comment below.  */
@@ -2742,6 +2745,7 @@ elf32_or1k_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
 #define elf_backend_want_plt_sym                0
 #define elf_backend_got_header_size             12
 #define elf_backend_dtrel_excludes_plt		1
+#define elf_backend_want_dynrelro		1
 
 #define bfd_elf32_bfd_link_hash_table_create    or1k_elf_link_hash_table_create
 #define elf_backend_copy_indirect_symbol        or1k_elf_copy_indirect_symbol

bfd/elf32-ppc.c

@@ -5806,6 +5806,8 @@ ppc_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
 
   if (ppc_elf_hash_entry (h)->has_sda_refs)
     s = htab->dynsbss;
+  else if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    s = htab->elf.sdynrelro;
   else
     s = htab->elf.sdynbss;
   BFD_ASSERT (s != NULL);
@@ -5820,6 +5822,8 @@ ppc_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
 
       if (ppc_elf_hash_entry (h)->has_sda_refs)
 	srel = htab->relsbss;
+      else if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+	srel = htab->elf.sreldynrelro;
       else
 	srel = htab->elf.srelbss;
       BFD_ASSERT (srel != NULL);
@@ -6636,6 +6640,7 @@ ppc_elf_size_dynamic_sections (bfd *output_bfd,
 	       || s == htab->elf.sgotplt
 	       || s == htab->sbss
 	       || s == htab->elf.sdynbss
+	       || s == htab->elf.sdynrelro
 	       || s == htab->dynsbss)
 	{
 	  /* Strip these too.  */
@@ -10356,6 +10361,8 @@ 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)
+	s = htab->elf.sreldynrelro;
       else
 	s = htab->elf.srelbss;
       BFD_ASSERT (s != NULL);
@@ -10893,6 +10900,7 @@ ppc_elf_finish_dynamic_sections (bfd *output_bfd,
 #endif
 
 #define elf_backend_plt_not_loaded	1
+#define elf_backend_want_dynrelro	1
 #define elf_backend_can_gc_sections	1
 #define elf_backend_can_refcount	1
 #define elf_backend_rela_normal		1

bfd/elf32-s390.c

@@ -1607,7 +1607,7 @@ elf_s390_adjust_dynamic_symbol (struct bfd_link_info *info,
 				struct elf_link_hash_entry *h)
 {
   struct elf_s390_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
 
   /* STT_GNU_IFUNC symbol must go through PLT. */
   if (s390_is_ifunc_symbol_p (h))
@@ -1757,14 +1757,22 @@ elf_s390_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_390_COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf32_External_Rela);
+      srel->size += sizeof (Elf32_External_Rela);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -2157,6 +2165,7 @@ elf_s390_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sgotplt
 	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro
 	  || s == htab->elf.iplt
 	  || s == htab->elf.igotplt
 	  || s == htab->irelifunc)
@@ -3800,6 +3809,7 @@ elf_s390_finish_dynamic_symbol (bfd *output_bfd,
   if (h->needs_copy)
     {
       Elf_Internal_Rela rela;
+      asection *s;
       bfd_byte *loc;
 
       /* This symbols needs a copy reloc.  Set it up.  */
@@ -3807,7 +3817,8 @@ elf_s390_finish_dynamic_symbol (bfd *output_bfd,
       if (h->dynindx == -1
 	  || (h->root.type != bfd_link_hash_defined
 	      && h->root.type != bfd_link_hash_defweak)
-	  || htab->elf.srelbss == NULL)
+	  || htab->elf.srelbss == NULL
+	  || htab->elf.sreldynrelro == NULL)
 	abort ();
 
       rela.r_offset = (h->root.u.def.value
@@ -3815,8 +3826,11 @@ 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;
-      loc = htab->elf.srelbss->contents;
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-      loc += htab->elf.srelbss->reloc_count++ * sizeof (Elf32_External_Rela);
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
+      loc = s->contents + s->reloc_count++ * sizeof (Elf32_External_Rela);
       bfd_elf32_swap_reloca_out (output_bfd, &rela, loc);
     }
 
@@ -4154,6 +4168,7 @@ elf32_s390_merge_private_bfd_data (bfd *ibfd, struct bfd_link_info *info)
 #define elf_backend_plt_readonly	1
 #define elf_backend_want_plt_sym	0
 #define elf_backend_got_header_size	12
+#define elf_backend_want_dynrelro	1
 #define elf_backend_rela_normal		1
 
 #define elf_info_to_howto		      elf_s390_info_to_howto

bfd/elf32-sparc.c

@@ -245,6 +245,7 @@ elf32_sparc_add_symbol_hook (bfd * abfd,
 #define elf_backend_plt_readonly 0
 #define elf_backend_want_plt_sym 1
 #define elf_backend_got_header_size 4
+#define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 
 #define elf_backend_add_symbol_hook		elf32_sparc_add_symbol_hook

bfd/elf32-tic6x.c

@@ -1860,13 +1860,15 @@ elf32_tic6x_finish_dynamic_symbol (bfd * output_bfd,
   if (h->needs_copy)
     {
       Elf_Internal_Rela rel;
+      asection *s;
 
       /* This symbol needs a copy reloc.  Set it up.  */
 
       if (h->dynindx == -1
 	  || (h->root.type != bfd_link_hash_defined
 	      && h->root.type != bfd_link_hash_defweak)
-	  || htab->elf.srelbss == NULL)
+	  || htab->elf.srelbss == NULL
+	  || htab->elf.sreldynrelro == NULL)
 	abort ();
 
       rel.r_offset = (h->root.u.def.value
@@ -1874,8 +1876,12 @@ 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)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
 
-      elf32_tic6x_install_rela (output_bfd, htab->elf.srelbss, &rel);
+      elf32_tic6x_install_rela (output_bfd, s, &rel);
     }
 
   /* Mark _DYNAMIC and _GLOBAL_OFFSET_TABLE_ as absolute.  */
@@ -2061,7 +2067,7 @@ elf32_tic6x_adjust_dynamic_symbol (struct bfd_link_info *info,
 {
   struct elf32_tic6x_link_hash_table *htab;
   bfd *dynobj;
-  asection *s;
+  asection *s, *srel;
 
   dynobj = elf_hash_table (info)->dynobj;
 
@@ -2146,14 +2152,22 @@ elf32_tic6x_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_C6000_COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf32_External_Rela);
+      srel->size += sizeof (Elf32_External_Rela);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -3376,7 +3390,8 @@ elf32_tic6x_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
       else if (s == htab->elf.splt
 	       || s == htab->elf.sgot
 	       || s == htab->elf.sgotplt
-	       || s == htab->elf.sdynbss)
+	       || s == htab->elf.sdynbss
+	       || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -4369,6 +4384,7 @@ elf32_tic6x_write_section (bfd *output_bfd,
 #define elf_backend_can_refcount	1
 #define elf_backend_want_got_plt	1
 #define elf_backend_want_dynbss		1
+#define elf_backend_want_dynrelro	1
 #define elf_backend_plt_readonly	1
 #define elf_backend_rela_normal		1
 #define elf_backend_got_header_size     8

bfd/elf32-tilegx.c

@@ -128,6 +128,7 @@ tilegx_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
 #define elf_backend_plt_alignment 6
 #define elf_backend_want_plt_sym 1
 #define elf_backend_got_header_size 4
+#define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 #define elf_backend_default_execstack 0
 

bfd/elf32-tilepro.c

@@ -2062,7 +2062,7 @@ tilepro_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct tilepro_elf_link_hash_table *htab;
   struct tilepro_elf_link_hash_entry * eh;
   struct tilepro_elf_dyn_relocs *p;
-  asection *s;
+  asection *s, *srel;
 
   htab = tilepro_elf_hash_table (info);
   BFD_ASSERT (htab != NULL);
@@ -2164,13 +2164,23 @@ tilepro_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rel.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += TILEPRO_ELF_RELA_BYTES;
+      srel->size += TILEPRO_ELF_RELA_BYTES;
       h->needs_copy = 1;
     }
 
-  return _bfd_elf_adjust_dynamic_copy (info, h, htab->elf.sdynbss);
+  return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
 /* Allocate space in .plt, .got and associated reloc sections for
@@ -2565,7 +2575,8 @@ tilepro_elf_size_dynamic_sections (bfd *output_bfd,
       if (s == htab->elf.splt
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sgotplt
-	  || s == htab->elf.sdynbss)
+	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -3797,14 +3808,15 @@ tilepro_elf_finish_dynamic_symbol (bfd *output_bfd,
       /* This symbols needs a copy reloc.  Set it up.  */
       BFD_ASSERT (h->dynindx != -1);
 
-      s = htab->elf.srelbss;
-      BFD_ASSERT (s != NULL);
-
       rela.r_offset = (h->root.u.def.value
 		       + h->root.u.def.section->output_section->vma
 		       + 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)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
       tilepro_elf_append_rela_32 (output_bfd, s, &rela);
     }
 
@@ -4045,6 +4057,7 @@ tilepro_additional_program_headers (bfd *abfd,
 #define elf_backend_plt_alignment 6
 #define elf_backend_want_plt_sym 1
 #define elf_backend_got_header_size GOT_ENTRY_SIZE
+#define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 #define elf_backend_default_execstack 0
 

bfd/elf64-mips.c

@@ -4467,6 +4467,7 @@ const struct elf_size_info mips_elf64_size_info =
 #define elf_backend_grok_psinfo		elf64_mips_grok_psinfo
 
 #define elf_backend_got_header_size	(8 * MIPS_RESERVED_GOTNO)
+#define elf_backend_want_dynrelro	1
 
 /* MIPS ELF64 can use a mixture of REL and RELA, but some Relocations
    work better/work only in RELA, so we default to this.  */

bfd/elf64-ppc.c

@@ -72,6 +72,7 @@ static bfd_vma opd_entry_value
 #define elf_backend_plt_alignment 3
 #define elf_backend_plt_not_loaded 1
 #define elf_backend_got_header_size 8
+#define elf_backend_want_dynrelro 1
 #define elf_backend_can_gc_sections 1
 #define elf_backend_can_refcount 1
 #define elf_backend_rela_normal 1
@@ -7235,7 +7236,7 @@ ppc64_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
 				 struct elf_link_hash_entry *h)
 {
   struct ppc_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
 
   htab = ppc_hash_table (info);
   if (htab == NULL)
@@ -7365,14 +7366,22 @@ ppc64_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rela.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf64_External_Rela);
+      srel->size += sizeof (Elf64_External_Rela);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -10174,7 +10183,8 @@ ppc64_elf_size_dynamic_sections (bfd *output_bfd,
 	       || s == htab->elf.splt
 	       || s == htab->elf.iplt
 	       || s == htab->glink
-	       || s == htab->elf.sdynbss)
+	       || s == htab->elf.sdynbss
+	       || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -10227,7 +10237,7 @@ ppc64_elf_size_dynamic_sections (bfd *output_bfd,
 	 but this way if it does we get a R_PPC64_NONE reloc in .rela
 	 sections instead of garbage.
 	 We also rely on the section contents being zero when writing
-	 the GOT.  */
+	 the GOT and .dynrelro.  */
       s->contents = bfd_zalloc (dynobj, s->size);
       if (s->contents == NULL)
 	return FALSE;
@@ -15421,11 +15431,13 @@ ppc64_elf_finish_dynamic_symbol (bfd *output_bfd,
   if (h->needs_copy)
     {
       /* This symbol needs a copy reloc.  Set it up.  */
+      asection *srel;
 
       if (h->dynindx == -1
 	  || (h->root.type != bfd_link_hash_defined
 	      && h->root.type != bfd_link_hash_defweak)
-	  || htab->elf.srelbss == NULL)
+	  || htab->elf.srelbss == NULL
+	  || htab->elf.sreldynrelro == NULL)
 	abort ();
 
       rela.r_offset = (h->root.u.def.value
@@ -15433,8 +15445,12 @@ 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;
-      loc = htab->elf.srelbss->contents;
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-      loc += htab->elf.srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
+	srel = htab->elf.sreldynrelro;
+      else
+	srel = htab->elf.srelbss;
+      loc = srel->contents;
+      loc += srel->reloc_count++ * sizeof (Elf64_External_Rela);
       bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
     }
 

bfd/elf64-s390.c

@@ -1541,7 +1541,7 @@ elf_s390_adjust_dynamic_symbol (struct bfd_link_info *info,
 				struct elf_link_hash_entry *h)
 {
   struct elf_s390_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
 
   /* STT_GNU_IFUNC symbol must go through PLT. */
   if (s390_is_ifunc_symbol_p (h))
@@ -1693,14 +1693,22 @@ elf_s390_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_390_COPY reloc to tell the dynamic linker to
      copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (Elf64_External_Rela);
+      srel->size += sizeof (Elf64_External_Rela);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -2099,6 +2107,7 @@ elf_s390_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sgotplt
 	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro
 	  || s == htab->elf.iplt
 	  || s == htab->elf.igotplt
 	  || s == htab->irelifunc)
@@ -3585,6 +3594,7 @@ elf_s390_finish_dynamic_symbol (bfd *output_bfd,
   if (h->needs_copy)
     {
       Elf_Internal_Rela rela;
+      asection *s;
       bfd_byte *loc;
 
       /* This symbols needs a copy reloc.  Set it up.  */
@@ -3600,8 +3610,11 @@ 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;
-      loc = htab->elf.srelbss->contents;
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-      loc += htab->elf.srelbss->reloc_count++ * sizeof (Elf64_External_Rela);
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
+      loc = s->contents + s->reloc_count++ * sizeof (Elf64_External_Rela);
       bfd_elf64_swap_reloca_out (output_bfd, &rela, loc);
     }
 
@@ -3979,6 +3992,7 @@ const struct elf_size_info s390_elf64_size_info =
 #define elf_backend_plt_readonly	1
 #define elf_backend_want_plt_sym	0
 #define elf_backend_got_header_size	24
+#define elf_backend_want_dynrelro	1
 #define elf_backend_rela_normal		1
 
 #define elf_info_to_howto		elf_s390_info_to_howto

bfd/elf64-sparc.c

@@ -920,6 +920,7 @@ const struct elf_size_info elf64_sparc_size_info =
 #define elf_backend_plt_readonly 0
 #define elf_backend_want_plt_sym 1
 #define elf_backend_got_header_size 8
+#define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 
 /* Section 5.2.4 of the ABI specifies a 256-byte boundary for the table.  */

bfd/elf64-tilegx.c

@@ -129,6 +129,7 @@ tilegx_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
 #define elf_backend_plt_alignment 6
 #define elf_backend_want_plt_sym 1
 #define elf_backend_got_header_size 8
+#define elf_backend_want_dynrelro 1
 #define elf_backend_rela_normal 1
 #define elf_backend_default_execstack 0
 

bfd/elf64-x86-64.c

@@ -2828,7 +2828,7 @@ elf_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
 				  struct elf_link_hash_entry *h)
 {
   struct elf_x86_64_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
   struct elf_x86_64_link_hash_entry *eh;
   struct elf_dyn_relocs *p;
 
@@ -2986,16 +2986,24 @@ elf_x86_64_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_X86_64_COPY reloc to tell the dynamic linker
      to copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
       const struct elf_backend_data *bed;
       bed = get_elf_backend_data (info->output_bfd);
-      htab->elf.srelbss->size += bed->s->sizeof_rela;
+      srel->size += bed->s->sizeof_rela;
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -3811,7 +3819,8 @@ elf_x86_64_size_dynamic_sections (bfd *output_bfd,
 	  || s == htab->plt_bnd
 	  || s == htab->plt_got
 	  || s == htab->plt_eh_frame
-	  || s == htab->elf.sdynbss)
+	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -6024,13 +6033,15 @@ do_glob_dat:
   if (h->needs_copy)
     {
       Elf_Internal_Rela rela;
+      asection *s;
 
       /* This symbol needs a copy reloc.  Set it up.  */
 
       if (h->dynindx == -1
 	  || (h->root.type != bfd_link_hash_defined
 	      && h->root.type != bfd_link_hash_defweak)
-	  || htab->elf.srelbss == NULL)
+	  || htab->elf.srelbss == NULL
+	  || htab->elf.sreldynrelro == NULL)
 	abort ();
 
       rela.r_offset = (h->root.u.def.value
@@ -6038,7 +6049,11 @@ 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;
-      elf_append_rela (output_bfd, htab->elf.srelbss, &rela);
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
+      elf_append_rela (output_bfd, s, &rela);
     }
 
   return TRUE;
@@ -6719,6 +6734,7 @@ static const struct bfd_elf_special_section
 #define elf_backend_extern_protected_data   1
 #define elf_backend_caches_rawsize	    1
 #define elf_backend_dtrel_excludes_plt	    1
+#define elf_backend_want_dynrelro	    1
 
 #define elf_info_to_howto		    elf_x86_64_info_to_howto
 

bfd/elflink.c

@@ -429,6 +429,19 @@ _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
 	return FALSE;
       htab->sdynbss = s;
 
+      if (bed->want_dynrelro)
+	{
+	  /* Similarly, but for symbols that were originally in read-only
+	     sections.  */
+	  s = bfd_make_section_anyway_with_flags (abfd, ".data.rel.ro",
+						  (SEC_ALLOC | SEC_READONLY
+						   | SEC_HAS_CONTENTS
+						   | SEC_LINKER_CREATED));
+	  if (s == NULL)
+	    return FALSE;
+	  htab->sdynrelro = s;
+	}
+
       /* The .rel[a].bss section holds copy relocs.  This section is not
 	 normally needed.  We need to create it here, though, so that the
 	 linker will map it to an output section.  We can't just create it
@@ -450,6 +463,19 @@ _bfd_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info)
 	      || ! bfd_set_section_alignment (abfd, s, bed->s->log_file_align))
 	    return FALSE;
 	  htab->srelbss = s;
+
+	  if (bed->want_dynrelro)
+	    {
+	      s = (bfd_make_section_anyway_with_flags
+		   (abfd, (bed->rela_plts_and_copies_p
+			   ? ".rela.data.rel.ro" : ".rel.data.rel.ro"),
+		    flags | SEC_READONLY));
+	      if (s == NULL
+		  || ! bfd_set_section_alignment (abfd, s,
+						  bed->s->log_file_align))
+		return FALSE;
+	      htab->sreldynrelro = s;
+	    }
 	}
     }
 

bfd/elfnn-aarch64.c

@@ -6833,7 +6833,7 @@ elfNN_aarch64_adjust_dynamic_symbol (struct bfd_link_info *info,
 				     struct elf_link_hash_entry *h)
 {
   struct elf_aarch64_link_hash_table *htab;
-  asection *s;
+  asection *s, *srel;
 
   /* If this is a function, put it in the procedure linkage table.  We
      will fill in the contents of the procedure linkage table later,
@@ -6910,14 +6910,22 @@ elfNN_aarch64_adjust_dynamic_symbol (struct bfd_link_info *info,
   /* We must generate a R_AARCH64_COPY reloc to tell the dynamic linker
      to copy the initial value out of the dynamic object and into the
      runtime process image.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->root.sdynrelro;
+      srel = htab->root.sreldynrelro;
+    }
+  else
+    {
+      s = htab->root.sdynbss;
+      srel = htab->root.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->root.srelbss->size += RELOC_SIZE (htab);
+      srel->size += RELOC_SIZE (htab);
       h->needs_copy = 1;
     }
 
-  s = htab->root.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 
 }
@@ -8517,7 +8525,8 @@ elfNN_aarch64_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
 	  || s == htab->root.sgotplt
 	  || s == htab->root.iplt
 	  || s == htab->root.igotplt
-	  || s == htab->root.sdynbss)
+	  || s == htab->root.sdynbss
+	  || s == htab->root.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -8921,6 +8930,7 @@ do_glob_dat:
   if (h->needs_copy)
     {
       Elf_Internal_Rela rela;
+      asection *s;
       bfd_byte *loc;
 
       /* This symbol needs a copy reloc.  Set it up.  */
@@ -8936,8 +8946,11 @@ 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;
-      loc = htab->root.srelbss->contents;
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-      loc += htab->root.srelbss->reloc_count++ * RELOC_SIZE (htab);
+	s = htab->root.sreldynrelro;
+      else
+	s = htab->root.srelbss;
+      loc = s->contents + s->reloc_count++ * RELOC_SIZE (htab);
       bfd_elfNN_swap_reloca_out (output_bfd, &rela, loc);
     }
 
@@ -9390,6 +9403,7 @@ const struct elf_size_info elfNN_aarch64_size_info =
 #define elf_backend_plt_readonly       1
 #define elf_backend_want_got_plt       1
 #define elf_backend_want_plt_sym       0
+#define elf_backend_want_dynrelro      1
 #define elf_backend_may_use_rel_p      0
 #define elf_backend_may_use_rela_p     1
 #define elf_backend_default_use_rela_p 1

bfd/elfnn-riscv.c

@@ -862,7 +862,7 @@ riscv_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct riscv_elf_link_hash_entry * eh;
   struct riscv_elf_dyn_relocs *p;
   bfd *dynobj;
-  asection *s;
+  asection *s, *srel;
 
   htab = riscv_elf_hash_table (info);
   BFD_ASSERT (htab != NULL);
@@ -965,16 +965,26 @@ riscv_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rel.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += sizeof (ElfNN_External_Rela);
+      srel->size += sizeof (ElfNN_External_Rela);
       h->needs_copy = 1;
     }
 
   if (eh->tls_type & ~GOT_NORMAL)
     return _bfd_elf_adjust_dynamic_copy (info, h, htab->sdyntdata);
 
-  return _bfd_elf_adjust_dynamic_copy (info, h, htab->elf.sdynbss);
+  return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
 /* Allocate space in .plt, .got and associated reloc sections for
@@ -1328,7 +1338,8 @@ riscv_elf_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info)
       if (s == htab->elf.splt
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sgotplt
-	  || s == htab->elf.sdynbss)
+	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -2389,6 +2400,7 @@ riscv_elf_finish_dynamic_symbol (bfd *output_bfd,
   if (h->needs_copy)
     {
       Elf_Internal_Rela rela;
+      asection *s;
 
       /* This symbols needs a copy reloc.  Set it up.  */
       BFD_ASSERT (h->dynindx != -1);
@@ -2396,7 +2408,11 @@ 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;
-      riscv_elf_append_rela (output_bfd, htab->elf.srelbss, &rela);
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
+      riscv_elf_append_rela (output_bfd, s, &rela);
     }
 
   /* Mark some specially defined symbols as absolute.  */
@@ -3213,6 +3229,7 @@ riscv_elf_grok_psinfo (bfd *abfd, Elf_Internal_Note *note)
 #define elf_backend_plt_alignment	4
 #define elf_backend_want_plt_sym	1
 #define elf_backend_got_header_size	(ARCH_SIZE / 8)
+#define elf_backend_want_dynrelro	1
 #define elf_backend_rela_normal		1
 #define elf_backend_default_execstack	0
 

bfd/elfxx-mips.c

@@ -9129,6 +9129,7 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   bfd *dynobj;
   struct mips_elf_link_hash_entry *hmips;
   struct mips_elf_link_hash_table *htab;
+  asection *s, *srel;
 
   htab = mips_elf_hash_table (info);
   BFD_ASSERT (htab != NULL);
@@ -9371,10 +9372,20 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      both the dynamic object and the regular object will refer to the
      same memory location for the variable.  */
 
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->root.sdynrelro;
+      srel = htab->root.sreldynrelro;
+    }
+  else
+    {
+      s = htab->root.sdynbss;
+      srel = htab->root.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0)
     {
       if (htab->is_vxworks)
-	htab->root.srelbss->size += sizeof (Elf32_External_Rela);
+	srel->size += sizeof (Elf32_External_Rela);
       else
 	mips_elf_allocate_dynamic_relocations (dynobj, info, 1);
       h->needs_copy = 1;
@@ -9384,7 +9395,7 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      dynamic will now refer to the local copy instead.  */
   hmips->possibly_dynamic_relocs = 0;
 
-  return _bfd_elf_adjust_dynamic_copy (info, h, htab->root.sdynbss);
+  return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
 /* This function is called after all the input files have been read,
@@ -9906,7 +9917,8 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd,
 	       && s != htab->root.sgot
 	       && s != htab->root.sgotplt
 	       && s != htab->sstubs
-	       && s != htab->root.sdynbss)
+	       && s != htab->root.sdynbss
+	       && s != htab->root.sdynrelro)
 	{
 	  /* It's not one of our sections, so don't allocate space.  */
 	  continue;
@@ -11296,6 +11308,8 @@ _bfd_mips_vxworks_finish_dynamic_symbol (bfd *output_bfd,
   if (h->needs_copy)
     {
       Elf_Internal_Rela rel;
+      asection *srel;
+      bfd_byte *loc;
 
       BFD_ASSERT (h->dynindx != -1);
 
@@ -11304,11 +11318,13 @@ _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;
-      bfd_elf32_swap_reloca_out (output_bfd, &rel,
+      if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
-				 htab->root.srelbss->contents
+	srel = htab->root.sreldynrelro;
-				 + (htab->root.srelbss->reloc_count
+      else
-				    * sizeof (Elf32_External_Rela)));
+	srel = htab->root.srelbss;
-      ++htab->root.srelbss->reloc_count;
+      loc = srel->contents + srel->reloc_count * sizeof (Elf32_External_Rela);
+      bfd_elf32_swap_reloca_out (output_bfd, &rel, loc);
+      ++srel->reloc_count;
     }
 
   /* If this is a mips16/microMIPS symbol, force the value to be even.  */

bfd/elfxx-sparc.c

@@ -2086,7 +2086,7 @@ _bfd_sparc_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct _bfd_sparc_elf_link_hash_table *htab;
   struct _bfd_sparc_elf_link_hash_entry * eh;
   struct _bfd_sparc_elf_dyn_relocs *p;
-  asection *s;
+  asection *s, *srel;
 
   htab = _bfd_sparc_elf_hash_table (info);
   BFD_ASSERT (htab != NULL);
@@ -2199,14 +2199,22 @@ _bfd_sparc_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rel.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += SPARC_ELF_RELA_BYTES (htab);
+      srel->size += SPARC_ELF_RELA_BYTES (htab);
       h->needs_copy = 1;
     }
 
-  s = htab->elf.sdynbss;
-
   return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
@@ -2686,6 +2694,7 @@ _bfd_sparc_elf_size_dynamic_sections (bfd *output_bfd,
       if (s == htab->elf.splt
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro
 	  || s == htab->elf.iplt
 	  || s == htab->elf.sgotplt)
 	{
@@ -4527,15 +4536,15 @@ _bfd_sparc_elf_finish_dynamic_symbol (bfd *output_bfd,
       /* This symbols needs a copy reloc.  Set it up.  */
       BFD_ASSERT (h->dynindx != -1);
 
-      s = bfd_get_linker_section (h->root.u.def.section->owner,
-				  ".rela.bss");
-      BFD_ASSERT (s != NULL);
-
       rela.r_offset = (h->root.u.def.value
 		       + h->root.u.def.section->output_section->vma
 		       + 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)
+	s = htab->elf.sreldynrelro;
+      else
+	s = htab->elf.srelbss;
       sparc_elf_append_rela (output_bfd, s, &rela);
     }
 

bfd/elfxx-target.h

@@ -108,6 +108,9 @@
 #ifndef elf_backend_want_dynbss
 #define elf_backend_want_dynbss 1
 #endif
+#ifndef elf_backend_want_dynrelro
+#define elf_backend_want_dynrelro 0
+#endif
 #ifndef elf_backend_want_p_paddr_set_to_zero
 #define elf_backend_want_p_paddr_set_to_zero 0
 #endif
@@ -855,6 +858,7 @@ static struct elf_backend_data elfNN_bed =
   elf_backend_can_refcount,
   elf_backend_want_got_sym,
   elf_backend_want_dynbss,
+  elf_backend_want_dynrelro,
   elf_backend_want_p_paddr_set_to_zero,
   elf_backend_default_execstack,
   elf_backend_caches_rawsize,

bfd/elfxx-tilegx.c

@@ -2327,7 +2327,7 @@ tilegx_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
   struct tilegx_elf_link_hash_entry * eh;
   struct tilegx_elf_dyn_relocs *p;
   bfd *dynobj;
-  asection *s;
+  asection *s, *srel;
 
   htab = tilegx_elf_hash_table (info);
   BFD_ASSERT (htab != NULL);
@@ -2431,13 +2431,23 @@ tilegx_elf_adjust_dynamic_symbol (struct bfd_link_info *info,
      to copy the initial value out of the dynamic object and into the
      runtime process image.  We need to remember the offset into the
      .rel.bss section we are going to use.  */
+  if ((h->root.u.def.section->flags & SEC_READONLY) != 0)
+    {
+      s = htab->elf.sdynrelro;
+      srel = htab->elf.sreldynrelro;
+    }
+  else
+    {
+      s = htab->elf.sdynbss;
+      srel = htab->elf.srelbss;
+    }
   if ((h->root.u.def.section->flags & SEC_ALLOC) != 0 && h->size != 0)
     {
-      htab->elf.srelbss->size += TILEGX_ELF_RELA_BYTES (htab);
+      srel->size += TILEGX_ELF_RELA_BYTES (htab);
       h->needs_copy = 1;
     }
 
-  return _bfd_elf_adjust_dynamic_copy (info, h, htab->elf.sdynbss);
+  return _bfd_elf_adjust_dynamic_copy (info, h, s);
 }
 
 /* Allocate space in .plt, .got and associated reloc sections for
@@ -2826,7 +2836,8 @@ tilegx_elf_size_dynamic_sections (bfd *output_bfd ATTRIBUTE_UNUSED,
       if (s == htab->elf.splt
 	  || s == htab->elf.sgot
 	  || s == htab->elf.sgotplt
-	  || s == htab->elf.sdynbss)
+	  || s == htab->elf.sdynbss
+	  || s == htab->elf.sdynrelro)
 	{
 	  /* Strip this section if we don't need it; see the
 	     comment below.  */
@@ -4187,6 +4198,9 @@ 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)
+	s = htab->elf.sreldynrelro;
+      else
 	s = htab->elf.srelbss;
       BFD_ASSERT (s != NULL);
 

ld/ChangeLog

@@ -1,3 +1,16 @@
+2016-12-26  Alan Modra  <amodra@gmail.com>
+
+	PR ld/20995
+	* testsuite/ld-arm/farcall-mixed-app-v5.d: Update to suit changed
+	stub hash table traversal caused by section id increment.  Accept
+	the previous output too.
+	* testsuite/ld-arm/farcall-mixed-app.d: Likewise.
+	* testsuite/ld-arm/farcall-mixed-lib-v4t.d: Likewise.
+	* testsuite/ld-arm/farcall-mixed-lib.d: Likewise.
+	* testsuite/ld-elf/pr20995a.s, * testsuite/ld-elf/pr20995b.s,
+	* testsuite/ld-elf/pr20995.r: New test.
+	* testsuite/ld-elf/elf.exp: Run it.
+
 2016-12-26  Alan Modra  <amodra@gmail.com>
 
 	* scripttempl/elf.sc: Don't use $BSS_NAME in .dynbss.

ld/testsuite/ld-arm/farcall-mixed-app-v5.d

@@ -50,8 +50,8 @@ Disassembly of section .far_arm:
 .* <app_func>:
  .*:	e1a0c00d 	mov	ip, sp
  .*:	e92dd800 	push	{fp, ip, lr, pc}
- .*:	eb0000.. 	bl	.* <__lib_func1_veneer>
+ .*:	eb00000(6|8) 	bl	.* <__lib_func1_veneer>
- .*:	eb0000.. 	bl	.* <__lib_func2_veneer>
+ .*:	eb00000(7|5) 	bl	.* <__lib_func2_veneer>
  .*:	e89d6800 	ldm	sp, {fp, sp, lr}
  .*:	e12fff1e 	bx	lr
  .*:	e1a00000 	nop			; \(mov r0, r0\)
@@ -61,12 +61,12 @@ Disassembly of section .far_arm:
  .*:	e12fff1e 	bx	lr
 #...
 
-.* <__lib_func1_veneer>:
+.* <__lib_func(1|2)_veneer>:
- .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func1_veneer\+0x4>
+ .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func(1|2)_veneer\+0x4>
- .*:	000081e8 	.word	0x000081e8
+ .*:	000081(e8|dc) 	.word	0x000081(e8|dc)
-.* <__lib_func2_veneer>:
+.* <__lib_func(2|1)_veneer>:
- .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func2_veneer\+0x4>
+ .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func(2|1)_veneer\+0x4>
- .*:	000081dc 	.word	0x000081dc
+ .*:	000081(dc|e8) 	.word	0x000081(dc|e8)
 
 Disassembly of section .far_thumb:
 

ld/testsuite/ld-arm/farcall-mixed-app.d

@@ -52,8 +52,8 @@ Disassembly of section .far_arm:
 .* <app_func>:
  .*:	e1a0c00d 	mov	ip, sp
  .*:	e92dd800 	push	{fp, ip, lr, pc}
- .*:	eb000006 	bl	.* <__lib_func1_veneer>
+ .*:	eb00000(6|8) 	bl	.* <__lib_func1_veneer>
- .*:	eb000007 	bl	.* <__lib_func2_veneer>
+ .*:	eb00000(7|5) 	bl	.* <__lib_func2_veneer>
  .*:	e89d6800 	ldm	sp, {fp, sp, lr}
  .*:	e12fff1e 	bx	lr
  .*:	e1a00000 	nop			; \(mov r0, r0\)
@@ -63,12 +63,12 @@ Disassembly of section .far_arm:
  .*:	e12fff1e 	bx	lr
 #...
 
-.* <__lib_func1_veneer>:
+.* <__lib_func(1|2)_veneer>:
- .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func1_veneer\+0x4>
+ .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func(1|2)_veneer\+0x4>
- .*:	000081ec 	.word	0x000081ec
+ .*:	000081e(c|0) 	.word	0x000081e(c|0)
-.* <__lib_func2_veneer>:
+.* <__lib_func(2|1)_veneer>:
- .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func2_veneer\+0x4>
+ .*:	e51ff004 	ldr	pc, \[pc, #-4\]	; .* <__lib_func(2|1)_veneer\+0x4>
- .*:	000081e0 	.word	0x000081e0
+ .*:	000081e(0|c) 	.word	0x000081e(0|c)
 
 Disassembly of section .far_thumb:
 

ld/testsuite/ld-arm/farcall-mixed-lib-v4t.d

@@ -87,24 +87,24 @@ Disassembly of section .text:
 	...
 
 .* <__real_lib_func3>:
- .*:	f000 f80e 	bl	2000390 <__app_func_from_thumb>
+ .*:	f000 f80(e|6) 	bl	.* <__app_func_from_thumb>
- .*:	f000 f804 	bl	2000380 <__app_func_weak_from_thumb>
+ .*:	f000 f80(4|c) 	bl	.* <__app_func_weak_from_thumb>
  .*:	4770      	bx	lr
 #...
 
-.* <__app_func_weak_from_thumb>:
+.* <__app_func(_weak)?_from_thumb>:
  .*:	4778      	bx	pc
  .*:	46c0      	nop			; \(mov r8, r8\)
- .*:	e59fc000 	ldr	ip, \[pc\]	; 200038c <__app_func_weak_from_thumb\+0xc>
+ .*:	e59fc000 	ldr	ip, \[pc\]	; 200038c <__app_func(_weak)?_from_thumb\+0xc>
  .*:	e08cf00f 	add	pc, ip, pc
- .*:	fdffff28 	.word	0xfdffff28
+ .*:	fdffff(2|1)8 	.word	0xfdffff(2|1)8
 
-.* <__app_func_from_thumb>:
+.* <__app_func(_weak)?_from_thumb>:
  .*:	4778      	bx	pc
  .*:	46c0      	nop			; \(mov r8, r8\)
- .*:	e59fc000 	ldr	ip, \[pc\]	; 200039c <__app_func_from_thumb\+0xc>
+ .*:	e59fc000 	ldr	ip, \[pc\]	; 200039c <__app_func(_weak)?_from_thumb\+0xc>
  .*:	e08cf00f 	add	pc, ip, pc
- .*:	fdffff08 	.word	0xfdffff08
+ .*:	fdffff(0|1)8 	.word	0xfdffff(0|1)8
 
 .* <lib_func3>:
  .*:	e59fc004 	ldr	ip, \[pc, #4\]	; 20003ac <lib_func3\+0xc>

ld/testsuite/ld-arm/farcall-mixed-lib.d

@@ -72,18 +72,18 @@ Disassembly of section .text:
 	...
 
 .* <lib_func3>:
- .*:	f000 e80c 	blx	200037c <__app_func_from_thumb>
+ .*:	f000 e80(c|6) 	blx	.* <__app_func_from_thumb>
- .*:	f000 e804 	blx	2000370 <__app_func_weak_from_thumb>
+ .*:	f000 e80(4|a) 	blx	.* <__app_func_weak_from_thumb>
  .*:	4770      	bx	lr
 #...
 
-.* <__app_func_weak_from_thumb>:
+.* <__app_func(_weak)?_from_thumb>:
- .*:	e59fc000 	ldr	ip, \[pc\]	; 2000378 <__app_func_weak_from_thumb\+0x8>
+ .*:	e59fc000 	ldr	ip, \[pc\]	; 2000378 <__app_func(_weak)?_from_thumb\+0x8>
  .*:	e08ff00c 	add	pc, pc, ip
- .*:	fdffff34 	.word	0xfdffff34
+ .*:	fdffff(34|28) 	.word	0xfdffff(34|28)
 
-.* <__app_func_from_thumb>:
+.* <__app_func(_weak)?_from_thumb>:
- .*:	e59fc000 	ldr	ip, \[pc\]	; 2000384 <__app_func_from_thumb\+0x8>
+ .*:	e59fc000 	ldr	ip, \[pc\]	; 2000384 <__app_func(_weak)?_from_thumb\+0x8>
  .*:	e08ff00c 	add	pc, pc, ip
- .*:	fdffff1c 	.word	0xfdffff1c
+ .*:	fdffff(1c|28) 	.word	0xfdffff(1c|28)
 	...

ld/testsuite/ld-elf/elf.exp

@@ -127,6 +127,20 @@ if { [check_shared_lib_support] } then {
 	    {symbolic-func.s} {{readelf {-r --wide} symbolic-func.r}}
 	    "symbolic-func.so"}
     }
+    # xfail on tic6x due to non-PIC/non-PID warnings
+    setup_xfail "tic6x-*-*"
+    run_ld_link_tests {
+	{"Build pr20995.so"
+	    "-shared" "" ""
+	    {pr20995b.s} {} "pr20995.so"}
+    }
+    # These targets don't copy dynamic variables into .bss.
+    setup_xfail "alpha-*-*" "bfin-*-*" "ia64-*-*" "xtensa-*-*"
+    run_ld_link_tests {
+	{"pr20995"
+	    "" "tmpdir/pr20995.so" ""
+	    {pr20995a.s} {{readelf {-S --wide} pr20995.r}} "pr20995"}
+    }
 }
 
 set test_list [lsort [glob -nocomplain $srcdir/$subdir/*.d]]

ld/testsuite/ld-elf/pr20995.r

@@ -0,0 +1,5 @@
+#...
+.* \.data\.rel\.ro +PROGBITS +[^ ]+ [^ ]+ [^ ]*[1-9a-f]0* .*
+#...
+.* \.bss +NOBITS +[^ ]+ [^ ]+ [^ ]*[1-9a-f]0* .*
+#...

ld/testsuite/ld-elf/pr20995a.s

@@ -0,0 +1,11 @@
+	.text
+	.global start
+start:
+	.global _start
+_start:
+	.global __start
+__start:
+	.global main
+main:
+	.dc.a rw
+	.dc.a ro

ld/testsuite/ld-elf/pr20995b.s

@@ -0,0 +1,13 @@
+	.data
+	.type rw,%object
+	.globl rw
+rw:
+	.dc.a 0
+	.size rw, . - rw
+
+	.text
+	.type ro,%object
+	.globl ro
+ro:
+	.dc.a 0
+	.size ro, . - ro