elf/dl-conflict.c

   1 /* Resolve conflicts against already prelinked libraries.
   2    Copyright (C) 2001-2017 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Jakub Jelinek <jakub@redhat.com>, 2001.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public License as
   8    published by the Free Software Foundation; either version 2.1 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If
  18    not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include <errno.h>
  21 #include <libintl.h>
  22 #include <stdlib.h>
  23 #include <unistd.h>
  24 #include <ldsodefs.h>
  25 #include <sys/mman.h>
  26 #include <sys/param.h>
  27 #include <sys/types.h>
  28 #include "dynamic-link.h"
  29
  30 void
  31 _dl_resolve_conflicts (struct link_map *l, ElfW(Rela) *conflict,
  32                        ElfW(Rela) *conflictend)
  33 {
  34 #if ! ELF_MACHINE_NO_RELA
  35   if (__glibc_unlikely (GLRO(dl_debug_mask) & DL_DEBUG_RELOC))
  36     _dl_debug_printf ("\nconflict processing: %s\n", DSO_FILENAME (l->l_name));
  37
  38   {
  39     /* Do the conflict relocation of the object and library GOT and other
  40        data.  */
  41
  42     /* This macro is used as a callback from the ELF_DYNAMIC_RELOCATE code.  */
  43 #define RESOLVE_MAP(ref, version, flags) (*ref = NULL, NULL)
  44 #define RESOLVE(ref, version, flags) (*ref = NULL, 0)
  45 #define RESOLVE_CONFLICT_FIND_MAP(map, r_offset) \
  46   do {                                                                        \
  47     while ((resolve_conflict_map->l_map_end < (ElfW(Addr)) (r_offset))        \
  48            || (resolve_conflict_map->l_map_start > (ElfW(Addr)) (r_offset)))  \
  49       resolve_conflict_map = resolve_conflict_map->l_next;                    \
  50                                                                               \
  51     (map) = resolve_conflict_map;                                             \
  52   } while (0)
  53
  54     /* Prelinking makes no sense for anything but the main namespace.  */
  55     assert (l->l_ns == LM_ID_BASE);
  56     struct link_map *resolve_conflict_map __attribute__ ((__unused__))
  57       = GL(dl_ns)[LM_ID_BASE]._ns_loaded;
  58
  59 #include "dynamic-link.h"
  60
  61     /* Override these, defined in dynamic-link.h.  */
  62 #undef CHECK_STATIC_TLS
  63 #define CHECK_STATIC_TLS(ref_map, sym_map) ((void) 0)
  64 #undef TRY_STATIC_TLS
  65 #define TRY_STATIC_TLS(ref_map, sym_map) (0)
  66
  67     GL(dl_num_cache_relocations) += conflictend - conflict;
  68
  69     for (; conflict < conflictend; ++conflict)
  70       elf_machine_rela (l, conflict, NULL, NULL, (void *) conflict->r_offset,
  71                         0);
  72   }
  73 #endif
  74 }