Disallow copy relocation against protected data symbol

We shpouldn't generate copy relocation to resolve reference to protected
data symbol defined in shared object with the NO_COPY_ON_PROTECTED
property.  This patch adds a bit to elf_obj_tdata as well as
elf_i386_link_hash_entry and elf_x86_64_link_hash_entry to track the bfd
with the NO_COPY_ON_PROTECTED property as well as protected symbol
defined in shared object.  extern_protected_data is set to FALSE if any
input relocatable file contains the NO_COPY_ON_PROTECTED property.

bfd/

	PR ld/21997
	* elf-bfd.h (elf_obj_tdata): Use ENUM_BITFIELD on object_id,
	dyn_lib_class and has_gnu_symbols.  Change bad_symtab to bitfield.
	Add a has_no_copy_on_protected bitfield.
	(elf_has_no_copy_on_protected): New.
	* elf-properties.c (_bfd_elf_parse_gnu_properties): Set
	elf_has_no_copy_on_protected for GNU_PROPERTY_NO_COPY_ON_PROTECTED.
	(elf_merge_gnu_property_list): Likewise.
	(_bfd_elf_link_setup_gnu_properties): Set extern_protected_data
	to FALSE for elf_has_no_copy_on_protected.
	* elf32-i386.c (SYMBOL_NO_COPYRELOC): New.
	(elf_i386_link_hash_entry): Add def_protected.
	(elf_i386_adjust_dynamic_symbol): Also check SYMBOL_NO_COPYRELOC
	when checking info->nocopyreloc.
	(elf_i386_link_setup_gnu_properties): Don't set
	extern_protected_data here.
	(elf_i386_merge_symbol_attribute): New function.
	(elf_backend_merge_symbol_attribute): New.
	* elf64-x86-64.c (SYMBOL_NO_COPYRELOC): New.
	(elf_x86_64_link_hash_entry): Add def_protected.
	(elf_x86_64_need_pic): Report protected symbol for def_protected.
	(elf_x86_64_adjust_dynamic_symbol): Also check SYMBOL_NO_COPYRELOC
	when checking info->nocopyreloc.
	(elf_x86_64_relocate_section): Also check for R_X86_64_PC32
	relocation run-time overflow and unresolvable R_X86_64_32S
	relocation against protected data symbol defined in shared object
	with GNU_PROPERTY_NO_COPY_ON_PROTECTED.
	(elf_x86_64_link_setup_gnu_properties): Don't set
	extern_protected_data here.
	(elf_x86_64_merge_symbol_attribute): New function.
	(elf_backend_merge_symbol_attribute): New.

ld/

	PR ld/21997
	* testsuite/ld-i386/i386.exp: Run PR ld/21997 tests.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
	* testsuite/ld-i386/pr21997-1a.S: New file.
	* testsuite/ld-i386/pr21997-1b.c: Likewise.
	* testsuite/ld-i386/pr21997-1c.S: Likewise.
	* testsuite/ld-x86-64/pr21997-1a.S: Likewise.
	* testsuite/ld-x86-64/pr21997-1a.err: Likewise.
	* testsuite/ld-x86-64/pr21997-1b.c: Likewise.
	* testsuite/ld-x86-64/pr21997-1b.err: Likewise.
	* testsuite/ld-x86-64/pr21997-1c.c: Likewise.

1 files changed, 9 insertions, 0 deletions

diff --git a/bfd/elf-properties.c b/bfd/elf-properties.c
index 13d620d..f367aa6 100644
--- a/bfd/elf-properties.c
+++ b/bfd/elf-properties.c
@@ -168,6 +168,7 @@ bad_size:
 		  return FALSE;
 		}
 	      prop = _bfd_elf_get_property (abfd, type, datasz);
+	      elf_has_no_copy_on_protected (abfd) = TRUE;
 	      prop->pr_kind = property_number;
 	      goto next;
 
@@ -290,6 +291,9 @@ elf_merge_gnu_property_list (struct bfd_link_info *info, bfd *abfd,
   for (p = *listp; p != NULL; p = p->next)
     if (elf_merge_gnu_properties (info, abfd, NULL, &p->property))
       {
+	if (p->property.pr_type == GNU_PROPERTY_NO_COPY_ON_PROTECTED)
+	  elf_has_no_copy_on_protected (abfd) = TRUE;
+
 	pr = _bfd_elf_get_property (abfd, p->property.pr_type,
 				    p->property.pr_datasz);
 	/* It must be a new property.  */
@@ -489,6 +493,11 @@ _bfd_elf_link_setup_gnu_properties (struct bfd_link_info *info)
 
       /* Cache the section contents for elf_link_input_bfd.  */
       elf_section_data (sec)->this_hdr.contents = contents;
+
+      /* If GNU_PROPERTY_NO_COPY_ON_PROTECTED is set, protected data
+	 symbol is defined in the shared object.  */
+      if (elf_has_no_copy_on_protected (first_pbfd))
+	info->extern_protected_data = FALSE;
     }
 
   return first_pbfd;