2005-02-06 H.J. Lu <hongjiu.lu@intel.com>
authorH.J. Lu <hjl.tools@gmail.com>
Sun, 6 Feb 2005 18:11:30 +0000 (18:11 +0000)
committerH.J. Lu <hjl.tools@gmail.com>
Sun, 6 Feb 2005 18:11:30 +0000 (18:11 +0000)
* elf32-i386.c (elf_i386_relocate_section): Disallow R_386_GOTOFF
against protected function when building shared library.

PR 584
* elf64-x86-64.c (is_32bit_relative_branch): New.
(elf64_x86_64_relocate_section): Alllow R_X86_64_PC32 on a
protected function symbol when building shared library for
32bit relative branch instruction.

bfd/ChangeLog
bfd/elf32-i386.c
bfd/elf64-x86-64.c

index 32eb9cd7db86e414af92bca226efc20b46830b23..461b27c5c4fdfc51a0ab459cdace15cf3761610f 100644 (file)
@@ -1,3 +1,14 @@
+2005-02-06  H.J. Lu  <hongjiu.lu@intel.com>
+
+       * elf32-i386.c (elf_i386_relocate_section): Disallow R_386_GOTOFF
+       against protected function when building shared library.
+
+       PR 584
+       * elf64-x86-64.c (is_32bit_relative_branch): New.
+       (elf64_x86_64_relocate_section): Alllow R_X86_64_PC32 on a
+       protected function symbol when building shared library for
+       32bit relative branch instruction.
+
 2005-02-06  Alan Modra  <amodra@bigpond.net.au>
 
        * elf64-ppc.c (add_symbol_adjust): Don't create fake descriptor
index 4785552187a76f40ad59dcaf1ab890d655b04001..9bab9be124435762a4b528884dfa732b62694e49 100644 (file)
@@ -2274,6 +2274,22 @@ elf_i386_relocate_section (bfd *output_bfd,
          /* Relocation is relative to the start of the global offset
             table.  */
 
+         /* Check to make sure it isn't a protected function symbol
+            for shared library since it may not be local when used
+            as function address.  */
+         if (info->shared
+             && h
+             && h->def_regular
+             && h->type == STT_FUNC
+             && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
+           {
+             (*_bfd_error_handler)
+               (_("%B: relocation R_386_GOTOFF against protected function `%s' can not be used when making a shared object"),
+                input_bfd, h->root.root.string);
+             bfd_set_error (bfd_error_bad_value);
+             return FALSE;
+           }
+
          /* Note that sgot is not involved in this
             calculation.  We always want the start of .got.plt.  If we
             defined _GLOBAL_OFFSET_TABLE_ in a different way, as is
index d5b38d830bf28de3da980d2c36112078912f2bf6..08e610b1db8724b3ccf737996ad7ddd174f6c908 100644 (file)
@@ -1745,6 +1745,24 @@ tpoff (struct bfd_link_info *info, bfd_vma address)
   return address - htab->tls_size - htab->tls_sec->vma;
 }
 
+/* Is the instruction before OFFSET in CONTENTS a 32bit relative
+   branch?  */
+
+static bfd_boolean
+is_32bit_relative_branch (bfd_byte *contents, bfd_vma offset)
+{
+  /* Opcode            Instruction
+     0xe8              call
+     0xe9              jump
+     0x0f 0x8x         conditional jump */
+  return ((offset > 0
+          && (contents [offset - 1] == 0xe8
+              || contents [offset - 1] == 0xe9))
+         || (offset > 1
+             && contents [offset - 2] == 0x0f
+             && (contents [offset - 1] & 0xf0) == 0x80));
+}
+
 /* Relocate an x86_64 ELF section.  */
 
 static bfd_boolean
@@ -1950,13 +1968,26 @@ elf64_x86_64_relocate_section (bfd *output_bfd, struct bfd_link_info *info,
          if (info->shared
              && !SYMBOL_REFERENCES_LOCAL (info, h)
              && (input_section->flags & SEC_ALLOC) != 0
-             && (input_section->flags & SEC_READONLY) != 0)
+             && (input_section->flags & SEC_READONLY) != 0
+             && (!h->def_regular
+                 || r_type != R_X86_64_PC32
+                 || h->type != STT_FUNC
+                 || ELF_ST_VISIBILITY (h->other) != STV_PROTECTED
+                 || !is_32bit_relative_branch (contents,
+                                               rel->r_offset)))
            {
-             (*_bfd_error_handler)
-               (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
-                input_bfd,
-                x86_64_elf_howto_table[r_type].name,
-                (h) ? h->root.root.string : "a local symbol");
+             if (h->def_regular
+                 && r_type == R_X86_64_PC32
+                 && h->type == STT_FUNC
+                 && ELF_ST_VISIBILITY (h->other) == STV_PROTECTED)
+               (*_bfd_error_handler)
+                  (_("%B: relocation R_X86_64_PC32 against protected function `%s' can not be used when making a shared object"),
+                   input_bfd, h->root.root.string);
+             else
+               (*_bfd_error_handler)
+                 (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"),
+                  input_bfd, x86_64_elf_howto_table[r_type].name,
+                  h->root.root.string);
              bfd_set_error (bfd_error_bad_value);
              return FALSE;
            }