Disallow copy relocation against protected data symbol

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.