elf: Add GNU_PROPERTY_1_NEEDED check

If GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS is set on any input
relocatable files:

1. Don't generate copy relocations.
2. Turn off extern_protected_data since it implies
GNU_PROPERTY_NO_COPY_ON_PROTECTED.
3. Treate reference to protected symbols with indirect external access
as local.
4. Set GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS on output.
5. When generating executable, clear this bit when there are non-GOT or
non-PLT relocations in input relocatable files without the bit set.
6. Add -z [no]indirect-extern-access to control indirect external access.

bfd/

	* elf-bfd (elf_obj_tdata): Add has_indirect_extern_access.
	(elf_has_indirect_extern_access): New.
	* elf-properties.c (_bfd_elf_parse_gnu_properties): Set
	elf_has_indirect_extern_access and elf_has_no_copy_on_protected
	when seeing GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS.
	(elf_write_gnu_propertie): Add an argument to pass link_info.
	Set needed_1_p for GNU_PROPERTY_1_NEEDED in memory.
	(_bfd_elf_link_setup_gnu_properties): Handle
	GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS for
	-z indirect-extern-access.  Set nocopyreloc to true and
	extern_protected_data to false for indirect external access.
	(_bfd_elf_convert_gnu_properties): Updated.
	* elf32-i386.c (elf_i386_check_relocs): Set
	non_got_ref_without_indirect_extern_access on legacy non-GOT or
	non-PLT references.
	* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
	* elflink.c (_bfd_elf_symbol_refs_local_p): Return true for
	STV_PROTECTED symbols with indirect external access.
	* elfxx-x86.c (_bfd_x86_elf_adjust_dynamic_symbol): Clear
	indirect_extern_access for legacy non-GOT/non-PLT references.
	* elfxx-x86.h (elf_x86_link_hash_entry): Add
	non_got_ref_without_indirect_extern_access.

include/

	* bfdlink.h (bfd_link_info): Add indirect_extern_access and
	needed_1_p.  Change nocopyreloc to int.

ld/

	* NEWS: Mention -z [no]indirect-extern-access
	* ld.texi: Document -z [no]indirect-extern-access
	* ldmain.c (main): Initialize link_info.indirect_extern_access
	to -1.
	* emulparams/extern_protected_data.sh: Support
	-z [no]indirect-extern-access.
	* testsuite/ld-elf/indirect-extern-access-1.rd: New file
	* testsuite/ld-elf/indirect-extern-access-1a.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-1b.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2.rd: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2a.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-2b.c: Likewise.
	* testsuite/ld-elf/indirect-extern-access-3.rd: Likewise.
	* testsuite/ld-elf/indirect-extern-access.S: Likewise.
	* testsuite/ld-elf/property-1_needed-1b.d: Likewise.
	* testsuite/ld-elf/property-1_needed-1c.d: Likewise.
	* testsuite/ld-x86-64/indirect-extern-access.rd: Likewise.
	* testsuite/ld-x86-64/protected-data-1.h: Likewise.
	* testsuite/ld-x86-64/protected-data-1a.c: Likewise.
	* testsuite/ld-x86-64/protected-data-1b.c: Likewise.
	* testsuite/ld-x86-64/protected-data-2a.S: Likewise.
	* testsuite/ld-x86-64/protected-data-2b.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2a.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2b.S: Likewise.
	* testsuite/ld-x86-64/protected-func-2c.c: Likewise.
	* testsuite/ld-elf/linux-x86.exp: Run test with
	GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS.
	* testsuite/ld-x86-64/x86-64.exp: Run tests for protected
	function and data with indirect external access.

1 files changed, 12 insertions, 0 deletions

diff --git a/ld/ld.texi b/ld/ld.texi
index 67c5083..b6d8dcc 100644
--- a/ld/ld.texi
+++ b/ld/ld.texi
@@ -1293,6 +1293,18 @@ Generate GNU_PROPERTY_X86_FEATURE_1_IBT in .note.gnu.property section
 to indicate compatibility with IBT.  This also implies @option{ibtplt}.
 Supported for Linux/i386 and Linux/x86_64.
 
+@item indirect-extern-access
+@itemx noindirect-extern-access
+Generate GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS in
+.note.gnu.property section to indicate that object file requires
+canonical function pointers and cannot be used with copy relocation.
+This option also implies @option{noextern-protected-data} and
+@option{nocopyreloc}.  Supported for i386 and x86-64.
+
+@option{noindirect-extern-access} removes
+GNU_PROPERTY_1_NEEDED_INDIRECT_EXTERN_ACCESS from .note.gnu.property
+section.
+
 @item initfirst
 This option is only meaningful when building a shared object.
 It marks the object so that its runtime initialization will occur