elf/dl-reloc-static-pie.c

   1 /* Support for relocating static PIE.
   2    Copyright (C) 2017-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #if ENABLE_STATIC_PIE
  20 #include <unistd.h>
  21 #include <ldsodefs.h>
  22 #include "dynamic-link.h"
  23
  24 /* Relocate static executable with PIE.  */
  25
  26 void
  27 _dl_relocate_static_pie (void)
  28 {
  29   struct link_map *main_map = _dl_get_dl_main_map ();
  30
  31 # define STATIC_PIE_BOOTSTRAP
  32 # define BOOTSTRAP_MAP (main_map)
  33 # define RESOLVE_MAP(sym, version, flags) BOOTSTRAP_MAP
  34 # include "dynamic-link.h"
  35
  36   /* Figure out the run-time load address of static PIE.  */
  37   main_map->l_addr = elf_machine_load_address ();
  38
  39   /* Read our own dynamic section and fill in the info array.  */
  40   main_map->l_ld = ((void *) main_map->l_addr + elf_machine_dynamic ());
  41   elf_get_dynamic_info (main_map, NULL);
  42
  43 # ifdef ELF_MACHINE_BEFORE_RTLD_RELOC
  44   ELF_MACHINE_BEFORE_RTLD_RELOC (main_map->l_info);
  45 # endif
  46
  47   /* Relocate ourselves so we can do normal function calls and
  48      data access using the global offset table.  */
  49   ELF_DYNAMIC_RELOCATE (main_map, 0, 0, 0);
  50   main_map->l_relocated = 1;
  51 }
  52 #endif