gdb/nat/linux-personality.c

   1 /* Disable address space randomization based on inferior personality.
   2
   3    Copyright (C) 2008-2021 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 "gdbsupport/common-defs.h"
  21 #include "nat/linux-personality.h"
  22
  23 #include <sys/personality.h>
  24
  25 /* See comment on nat/linux-personality.h.  */
  26
  27 maybe_disable_address_space_randomization::
  28 maybe_disable_address_space_randomization (int disable_randomization)
  29   : m_personality_set (false),
  30     m_personality_orig (0)
  31 {
  32   if (disable_randomization)
  33     {
  34       errno = 0;
  35       m_personality_orig = personality (0xffffffff);
  36       if (errno == 0 && !(m_personality_orig & ADDR_NO_RANDOMIZE))
  37         {
  38           m_personality_set = true;
  39           personality (m_personality_orig | ADDR_NO_RANDOMIZE);
  40         }
  41       if (errno != 0 || (m_personality_set
  42                          && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
  43         warning (_("Error disabling address space randomization: %s"),
  44                  safe_strerror (errno));
  45     }
  46 }
  47
  48 maybe_disable_address_space_randomization::
  49 ~maybe_disable_address_space_randomization ()
  50 {
  51   if (m_personality_set)
  52     {
  53       errno = 0;
  54       personality (m_personality_orig);
  55       if (errno != 0)
  56         warning (_("Error restoring address space randomization: %s"),
  57                  safe_strerror (errno));
  58     }
  59 }