1 /* $OpenBSD: stack_protector.c,v 1.17 2015/09/10 18:13:46 guenther 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 <string.h> 32 #include <syslog.h> 33 #include <unistd.h> 34 35 void 36 __stack_smash_handler(const char func[], int damaged) 37 { 38 struct syslog_data sdata = SYSLOG_DATA_INIT; 39 const char message[] = "stack overflow in function %s"; 40 struct sigaction sa; 41 sigset_t mask; 42 43 /* Immediately block all signal handlers from running code */ 44 sigfillset(&mask); 45 sigdelset(&mask, SIGABRT); 46 sigprocmask(SIG_BLOCK, &mask, NULL); 47 48 /* This may fail on a chroot jail... */ 49 syslog_r(LOG_CRIT, &sdata, message, func); 50 51 bzero(&sa, sizeof(struct sigaction)); 52 sigemptyset(&sa.sa_mask); 53 sa.sa_flags = 0; 54 sa.sa_handler = SIG_DFL; 55 sigaction(SIGABRT, &sa, NULL); 56 57 kill(getpid(), SIGABRT); 58 59 _exit(127); 60 } 61 DEF_STRONG(__stack_smash_handler); 62