glibc/sysdeps/x86/tst-cet-legacy-5.c
H.J. Lu 9e38f455a6 x86: Add --enable-cet=permissive
When CET is enabled, it is an error to dlopen a non CET enabled shared
library in CET enabled application.  It may be desirable to make CET
permissive, that is disable CET when dlopening a non CET enabled shared
library.  With the new --enable-cet=permissive configure option, CET is
disabled when dlopening a non CET enabled shared library.

Add DEFAULT_DL_X86_CET_CONTROL to config.h.in:

 /* The default value of x86 CET control.  */
 #define DEFAULT_DL_X86_CET_CONTROL cet_elf_property

which enables CET features based on ELF property note.

--enable-cet=permissive it to

 /* The default value of x86 CET control.  */
 #define DEFAULT_DL_X86_CET_CONTROL cet_permissive

which enables CET features permissively.

Update tst-cet-legacy-5a, tst-cet-legacy-5b, tst-cet-legacy-6a and
tst-cet-legacy-6b to check --enable-cet and --enable-cet=permissive.
2020-05-18 08:38:53 -07:00

87 lines
2.2 KiB
C

/* Check compatibility of CET-enabled executable with dlopened legacy
shared object.
Copyright (C) 2019-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <x86intrin.h>
#include <support/check.h>
#if defined CET_IS_PERMISSIVE || defined CET_DISABLED_BY_ENV
# define CET_MAYBE_DISABLED 1
#else
# define CET_MAYBE_DISABLED 0
#endif
static void
do_test_1 (const char *modname, bool fail)
{
int (*fp) (void);
void *h;
h = dlopen (modname, RTLD_LAZY);
if (h == NULL)
{
const char *err = dlerror ();
if (fail)
{
if (strstr (err, "rebuild shared object with SHSTK support enabled")
== NULL)
FAIL_EXIT1 ("incorrect dlopen '%s' error: %s\n", modname, err);
return;
}
FAIL_EXIT1 ("cannot open '%s': %s\n", modname, err);
}
/* NB: dlopen should never fail on non-CET platforms. If SHSTK is
disabled, assuming IBT is also disabled. */
bool cet_enabled = _get_ssp () != 0 && !CET_MAYBE_DISABLED;
if (fail && cet_enabled)
FAIL_EXIT1 ("dlopen should have failed\n");
fp = dlsym (h, "test");
if (fp == NULL)
{
printf ("cannot get symbol 'test': %s\n", dlerror ());
exit (1);
}
if (fp () != 0)
{
puts ("test () != 0");
exit (1);
}
dlclose (h);
}
static int
do_test (void)
{
do_test_1 ("tst-cet-legacy-mod-5a.so", true);
do_test_1 ("tst-cet-legacy-mod-5b.so", false);
return 0;
}
#include <support/test-driver.c>