Finish IFUNC support for x86 and x86-64.

Add support for the IRELAIVE relocation and IFUNC in static executables.

2 files changed, 56 insertions, 0 deletions

diff --git a/sysdeps/x86_64/dl-irel.h b/sysdeps/x86_64/dl-irel.h
new file mode 100644
index 0000000000..442ab71d26
--- /dev/null
+++ b/sysdeps/x86_64/dl-irel.h
@@ -0,0 +1,44 @@
+/* Machine-dependent ELF indirect relocation inline functions.
+   x86-64 version.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#ifndef _DL_IREL_H
+#define _DL_IREL_H
+
+#include <unistd.h>
+
+#define ELF_MACHINE_IRELA	1
+
+static inline void
+__attribute ((always_inline))
+elf_irela (const Elf64_Rela *reloc)
+{
+  Elf64_Addr *const reloc_addr = (void *) reloc->r_offset;
+  const unsigned long int r_type = ELF64_R_TYPE (reloc->r_info);
+
+  if (__builtin_expect (r_type == R_X86_64_IRELATIVE, 1))
+    {
+      Elf64_Addr value = ((Elf64_Addr (*) (void)) reloc->r_addend) ();
+      *reloc_addr = value;
+    }
+  else
+    _exit (-1);
+}
+
+#endif /* dl-irel.h */
diff --git a/sysdeps/x86_64/dl-machine.h b/sysdeps/x86_64/dl-machine.h
index 4444ae0a71..1b5ce8e981 100644
--- a/sysdeps/x86_64/dl-machine.h
+++ b/sysdeps/x86_64/dl-machine.h
@@ -297,6 +297,7 @@ elf_machine_rela (struct link_map *map, const Elf64_Rela *reloc,
 			  : (Elf64_Addr) sym_map->l_addr + sym->st_value);
 
       if (sym != NULL
+	  && __builtin_expect (sym->st_shndx != SHN_UNDEF, 1)
 	  && __builtin_expect (ELFW(ST_TYPE) (sym->st_info) == STT_GNU_IFUNC,
 			       0))
 	value = ((Elf64_Addr (*) (void)) value) ();
@@ -442,6 +443,11 @@ elf_machine_rela (struct link_map *map, const Elf64_Rela *reloc,
 	    }
 	  break;
 #  endif
+	case R_X86_64_IRELATIVE:
+	  value = map->l_addr + reloc->r_addend;
+	  value = ((Elf64_Addr (*) (void)) value) ();
+	  *reloc_addr = value;
+	  break;
 	default:
 	  _dl_reloc_bad_type (map, r_type, 0);
 	  break;
@@ -488,6 +494,12 @@ elf_machine_lazy_rel (struct link_map *map,
       td->entry = (void*)(D_PTR (map, l_info[ADDRIDX (DT_TLSDESC_PLT)])
 			  + map->l_addr);
     }
+  else if (__builtin_expect (r_type == R_X86_64_IRELATIVE, 0))
+    {
+      Elf64_Addr value = map->l_addr + reloc->r_addend;
+      value = ((Elf64_Addr (*) (void)) value) ();
+      *reloc_addr = value;
+    }
   else
     _dl_reloc_bad_type (map, r_type, 1);
 }