1 /* $OpenBSD: t_sigaltstack.c,v 1.2 2021/12/13 16:56:48 deraadt Exp $ */
2 /* $NetBSD: t_sigaltstack.c,v 1.2 2020/05/01 21:35:30 christos Exp $ */
3
4 /*-
5 * Copyright (c) 2020 The NetBSD Foundation, Inc.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
19 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
21 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 * POSSIBILITY OF SUCH DAMAGE.
28 */
29 #include "macros.h"
30
31 #include <signal.h>
32 #include <stdbool.h>
33
34 #include "atf-c.h"
35
36 #include "h_macros.h"
37
38 static stack_t sigstk;
39 static bool handler_called;
40 static bool handler_use_altstack;
41
42 static void
handler(int signo __unused)43 handler(int signo __unused)
44 {
45 char sp[128];
46
47 handler_called = true;
48
49 /* checking if the stack pointer is within the range of altstack */
50 if ((char *)sigstk.ss_sp <= sp &&
51 ((char *)sigstk.ss_sp + sigstk.ss_size) > sp)
52 handler_use_altstack = true;
53 else
54 handler_use_altstack = false;
55 }
56
57 ATF_TC(sigaltstack_onstack);
ATF_TC_HEAD(sigaltstack_onstack,tc)58 ATF_TC_HEAD(sigaltstack_onstack, tc)
59 {
60 atf_tc_set_md_var(tc, "descr",
61 "Checks for using signal stack with SA_ONSTACK");
62 }
63
ATF_TC_BODY(sigaltstack_onstack,tc)64 ATF_TC_BODY(sigaltstack_onstack, tc)
65 {
66 struct sigaction sa;
67 int i;
68
69 /* set a signal handler use alternative stack */
70 memset(&sigstk, 0, sizeof(sigstk));
71 sigstk.ss_sp = malloc(SIGSTKSZ);
72 ATF_REQUIRE(sigstk.ss_sp != NULL);
73 sigstk.ss_size = SIGSTKSZ;
74 sigstk.ss_flags = 0;
75 ATF_REQUIRE(sigaltstack(&sigstk, 0) == 0);
76
77 sigemptyset(&sa.sa_mask);
78 sa.sa_handler = handler;
79 sa.sa_flags = SA_ONSTACK;
80 sigaction(SIGUSR1, &sa, NULL);
81
82 /* test several times */
83 for (i = 1; i <= 5; i++) {
84 handler_called = false;
85 kill(getpid(), SIGUSR1);
86
87 if (!handler_called)
88 atf_tc_fail("signal handler wasn't called (count=%d)", i);
89 if (!handler_use_altstack)
90 atf_tc_fail("alternative stack wasn't used (count=%d)", i);
91 }
92 }
93
ATF_TP_ADD_TCS(tp)94 ATF_TP_ADD_TCS(tp)
95 {
96 ATF_TP_ADD_TC(tp, sigaltstack_onstack);
97
98 return atf_no_error();
99 }
100