1 /* Check compatibility of CET-enabled executable with dlopened legacy
2 shared object.
3 Copyright (C) 2019-2021 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
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
8 License as published by the Free Software Foundation; either
9 version 2.1 of the 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; if not, see
18 <https://www.gnu.org/licenses/>. */
19
20 #include <dlfcn.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <stdbool.h>
24 #include <string.h>
25 #include <x86intrin.h>
26 #include <support/check.h>
27
28 #if defined CET_IS_PERMISSIVE || defined CET_DISABLED_BY_ENV
29 # define CET_MAYBE_DISABLED 1
30 #else
31 # define CET_MAYBE_DISABLED 0
32 #endif
33
34 static void
do_test_1(const char * modname,bool fail)35 do_test_1 (const char *modname, bool fail)
36 {
37 int (*fp) (void);
38 void *h;
39
40 /* NB: dlopen should never fail on non-CET platforms. If SHSTK is
41 disabled, assuming IBT is also disabled. */
42 bool cet_enabled = _get_ssp () != 0 && !CET_MAYBE_DISABLED;
43 if (!cet_enabled)
44 fail = false;
45
46 h = dlopen (modname, RTLD_LAZY);
47 if (h == NULL)
48 {
49 const char *err = dlerror ();
50 if (fail)
51 {
52 if (strstr (err, "rebuild shared object with SHSTK support enabled")
53 == NULL)
54 FAIL_EXIT1 ("incorrect dlopen '%s' error: %s\n", modname, err);
55
56 return;
57 }
58
59 FAIL_EXIT1 ("cannot open '%s': %s\n", modname, err);
60 }
61
62 if (fail)
63 FAIL_EXIT1 ("dlopen should have failed\n");
64
65 fp = dlsym (h, "test");
66 if (fp == NULL)
67 {
68 printf ("cannot get symbol 'test': %s\n", dlerror ());
69 exit (1);
70 }
71
72 if (fp () != 0)
73 {
74 puts ("test () != 0");
75 exit (1);
76 }
77
78 dlclose (h);
79 }
80
81 static int
do_test(void)82 do_test (void)
83 {
84 do_test_1 ("tst-cet-legacy-mod-6a.so", true);
85 do_test_1 ("tst-cet-legacy-mod-6b.so", false);
86 return 0;
87 }
88
89 #include <support/test-driver.c>
90