GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/sys/stack_protector.c Lines: 0 18 0.0 %
Date: 2017-11-13 Branches: 0 0 0.0 %

Line Branch Exec Source
1
/*	$OpenBSD: stack_protector.c,v 1.23 2016/03/21 22:41:28 bluhm Exp $	*/
2
3
/*
4
 * Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
5
 * All rights reserved.
6
 *
7
 * Redistribution and use in source and binary forms, with or without
8
 * modification, are permitted provided that the following conditions
9
 * are met:
10
 * 1. Redistributions of source code must retain the above copyright
11
 *    notice, this list of conditions and the following disclaimer.
12
 * 2. Redistributions in binary form must reproduce the above copyright
13
 *    notice, this list of conditions and the following disclaimer in the
14
 *    documentation and/or other materials provided with the distribution.
15
 *
16
 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
17
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19
 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT,
20
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
25
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26
 * POSSIBILITY OF SUCH DAMAGE.
27
 *
28
 */
29
30
#include <signal.h>
31
#include <stdlib.h>
32
#include <string.h>
33
#include <syslog.h>
34
#include <unistd.h>
35
36
/*
37
 * Note: test below is for PIC not __PIC__.  This code must only be included
38
 * in the shared library and not in libc.a, but __PIC__ is set for libc.a
39
 * objects where PIE is supported
40
 *
41
 * XXX would this work? #if defined(__PIC__) && !defined(__PIE__)
42
 * XXX any archs which are always PIC (like mips64) but don't have PIE?
43
 */
44
#ifdef PIC
45
#include <../csu/os-note-elf.h>
46
47
long __guard_local __dso_hidden __attribute__((section(".openbsd.randomdata")));
48
#endif /* PIC */
49
50
void
51
__stack_smash_handler(const char func[], int damaged)
52
{
53
	struct sigaction sa;
54
	sigset_t mask;
55
	char buf[1024];
56
57
	/* Immediately block all signal handlers from running code */
58
	sigfillset(&mask);
59
	sigdelset(&mask, SIGABRT);
60
	sigprocmask(SIG_SETMASK, &mask, NULL);
61
62
	/* <10> is LOG_CRIT */
63
	strlcpy(buf, "<10>", sizeof buf);
64
65
	/* Make sure progname does not fill the whole buffer */
66
	strlcat(buf, __progname, sizeof(buf) / 2 );
67
68
	strlcat(buf, ": stack overflow in function ", sizeof buf);
69
	strlcat(buf, func, sizeof buf);
70
71
	sendsyslog(buf, strlen(buf), LOG_CONS);
72
73
	memset(&sa, 0, sizeof(sa));
74
	sigemptyset(&sa.sa_mask);
75
	sa.sa_flags = 0;
76
	sa.sa_handler = SIG_DFL;
77
	sigaction(SIGABRT, &sa, NULL);
78
79
	thrkill(0, SIGABRT, NULL);
80
81
	_exit(127);
82
}
83
DEF_STRONG(__stack_smash_handler);