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2 commits

Author SHA1 Message Date
Fangrui Song
d19a265487 x86: Make protected symbols local for -shared
Call _bfd_elf_symbol_refs_local_p with local_protected==true.  This has
2 noticeable effects for -shared:

* GOT-generating relocations referencing a protected data symbol no
  longer lead to a GLOB_DAT (similar to a hidden symbol).
* Direct access relocations (e.g. R_X86_64_PC32) no longer has the
  confusing diagnostic below.

    __attribute__((visibility("protected"))) void *foo() {
      return (void *)foo;
    }

    // gcc -fpic -shared -fuse-ld=bfd
    relocation R_X86_64_PC32 against protected symbol `foo' can not be used when making a shared object

The new behavior matches arm, aarch64 (commit
83c325007c), and powerpc ports, and other
linkers: gold and ld.lld.

Note: if some code tries to use direct access relocations to take the
address of foo, the pointer equality will break, but the error should be
reported on the executable link, not on the innocent shared object link.
glibc 2.36 will give a warning at relocation resolving time.

With this change, `#define elf_backend_extern_protected_data 1` is no
longer effective.  Just remove it.

Remove the test "Run protected-func-1 without PIE" since -fno-pic
address taken operation in the executable doesn't work with protected
symbol in a shared object by default.  Similarly, remove
protected-data-1a and protected-data-1b.  protected-data-1b can be made
working by removing HAVE_LD_PIE_COPYRELOC from GCC
(https://sourceware.org/pipermail/gcc-patches/2022-June/596678.html).
2022-07-19 08:41:52 -07:00
H.J. Lu
41bed6dd8a bfd/
2008-03-16  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/5789
	PR ld/5943
	* elf32-i386.c  (elf_i386_relocate_section): Issue an error
	for R_386_GOTOFF relocaton against undefined hidden/internal
	symbols when building a shared object.

	* elf64-x86-64.c (elf64_x86_64_relocate_section): Issue an
	error for R_X86_64_PC8/R_X86_64_PC16/R_X86_64_PC32
	relocaton against undefined hidden/internal symbols when
	building a shared object.
	(elf64_x86_64_finish_dynamic_symbol): Return FALSE when symbol
	is referenced locally, but isn't defined in a regular file.

ld/testsuite/

2008-03-16  H.J. Lu  <hongjiu.lu@intel.com>

	PR ld/5789
	PR ld/5943
	* ld-i386/hidden1.d: New.
	* ld-i386/hidden1.s: Likewise.
	* ld-i386/hidden2.d: Likewise.
	* ld-i386/hidden2.s: Likewise.
	* ld-i386/hidden3.d: Likewise.
	* ld-i386/hidden4.s: Likewise.
	* ld-i386/protected1.d: Likewise.
	* ld-i386/protected1.s: Likewise.
	* ld-i386/protected2.d: Likewise.
	* ld-i386/protected2.s: Likewise.
	* ld-i386/protected3.d: Likewise.
	* ld-i386/protected3.s: Likewise.
	* ld-x86-64/hidden1.d: Likewise.
	* ld-x86-64/hidden1.s: Likewise.
	* ld-x86-64/hidden2.d: Likewise.
	* ld-x86-64/hidden2.s: Likewise.
	* ld-x86-64/hidden3.d: Likewise.
	* ld-x86-64/hidden3.s: Likewise.
	* ld-x86-64/protected1.d: Likewise.
	* ld-x86-64/protected1.s: Likewise.
	* ld-x86-64/protected2.d: Likewise.
	* ld-x86-64/protected2.s: Likewise.
	* ld-x86-64/protected3.d: Likewise.
	* ld-x86-64/protected3.s: Likewise.

	* ld-i386/i386.exp: Run hidden1, hidden2, hidden3, protected1,
	protected2 and protected3.
	* ld-x86-64/x86-64.exp: Likewise.
2008-03-16 22:26:23 +00:00