binutils-gdb/gdb/nat/linux-personality.c

95 lines
2.9 KiB
C

/* Disable address space randomization based on inferior personality.
Copyright (C) 2008-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "common-defs.h"
#include "nat/linux-personality.h"
#ifdef HAVE_PERSONALITY
# include <sys/personality.h>
# if !HAVE_DECL_ADDR_NO_RANDOMIZE
# define ADDR_NO_RANDOMIZE 0x0040000
# endif /* ! HAVE_DECL_ADDR_NO_RANDOMIZE */
#endif /* HAVE_PERSONALITY */
#ifdef HAVE_PERSONALITY
/* Restore address space randomization of the inferior. ARG is the
original inferior's personality value before the address space
randomization was disabled. */
static void
restore_personality (void *arg)
{
int personality_orig = (int) (uintptr_t) arg;
errno = 0;
personality (personality_orig);
if (errno != 0)
warning (_("Error restoring address space randomization: %s"),
safe_strerror (errno));
}
#endif /* HAVE_PERSONALITY */
/* Return a cleanup responsible for restoring the inferior's
personality (and restoring the inferior's address space
randomization) if HAVE_PERSONALITY and if PERSONALITY_SET is not
zero; return a null cleanup if not HAVE_PERSONALITY or if
PERSONALITY_SET is zero. */
static struct cleanup *
make_disable_asr_cleanup (int personality_set, int personality_orig)
{
#ifdef HAVE_PERSONALITY
if (personality_set != 0)
return make_cleanup (restore_personality,
(void *) (uintptr_t) personality_orig);
#endif /* HAVE_PERSONALITY */
return make_cleanup (null_cleanup, NULL);
}
/* See comment on nat/linux-personality.h. */
struct cleanup *
maybe_disable_address_space_randomization (int disable_randomization)
{
int personality_orig = 0;
int personality_set = 0;
#ifdef HAVE_PERSONALITY
if (disable_randomization)
{
errno = 0;
personality_orig = personality (0xffffffff);
if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE))
{
personality_set = 1;
personality (personality_orig | ADDR_NO_RANDOMIZE);
}
if (errno != 0 || (personality_set
&& !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
warning (_("Error disabling address space randomization: %s"),
safe_strerror (errno));
}
#endif /* HAVE_PERSONALITY */
return make_disable_asr_cleanup (personality_set,
personality_orig);
}