gdb/nat/linux-personality.c

   1 /* Disable address space randomization based on inferior personality.
   2
   3    Copyright (C) 2008-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "nat/linux-personality.h"
  21
  22 #include <sys/personality.h>
  23
  24 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
  25 #  define ADDR_NO_RANDOMIZE 0x0040000
  26 # endif /* ! HAVE_DECL_ADDR_NO_RANDOMIZE */
  27
  28 /* See comment on nat/linux-personality.h.  */
  29
  30 maybe_disable_address_space_randomization::
  31 maybe_disable_address_space_randomization (int disable_randomization)
  32   : m_personality_set (false),
  33     m_personality_orig (0)
  34 {
  35   if (disable_randomization)
  36     {
  37       errno = 0;
  38       m_personality_orig = personality (0xffffffff);
  39       if (errno == 0 && !(m_personality_orig & ADDR_NO_RANDOMIZE))
  40         {
  41           m_personality_set = true;
  42           personality (m_personality_orig | ADDR_NO_RANDOMIZE);
  43         }
  44       if (errno != 0 || (m_personality_set
  45                          && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
  46         warning (_("Error disabling address space randomization: %s"),
  47                  safe_strerror (errno));
  48     }
  49 }
  50
  51 maybe_disable_address_space_randomization::
  52 ~maybe_disable_address_space_randomization ()
  53 {
  54   if (m_personality_set)
  55     {
  56       errno = 0;
  57       personality (m_personality_orig);
  58       if (errno != 0)
  59         warning (_("Error restoring address space randomization: %s"),
  60                  safe_strerror (errno));
  61     }
  62 }