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--- Libc/Libc-391.1.21/sys/OpenBSD/stack_protector.c
+++ Libc/Libc-763.11/sys/OpenBSD/stack_protector.c
@@ -1,3 +1,5 @@
+/* $OpenBSD: stack_protector.c,v 1.10 2006/03/31 05:34:44 deraadt Exp $ */
+
/*
* Copyright (c) 2002 Hiroaki Etoh, Federico G. Schwindt, and Miodrag Vallat.
* All rights reserved.
@@ -25,13 +27,14 @@
*
*/
-#if defined(LIBC_SCCS) && !defined(list)
-static char rcsid[] = "$OpenBSD: stack_protector.c,v 1.3 2002/12/10 08:53:42 etoh Exp $";
-#endif
-
#include <sys/param.h>
#include <sys/sysctl.h>
+#include <signal.h>
+#include <string.h>
#include <syslog.h>
+#include <unistd.h>
+
+extern int __sysctl(int *, u_int, void *, size_t *, void *, size_t);
long __guard[8] = {0, 0, 0, 0, 0, 0, 0, 0};
static void __guard_setup(void) __attribute__ ((constructor));
@@ -40,36 +43,50 @@
static void
__guard_setup(void)
{
- int fd;
- if (__guard[0]!=0) return;
- fd = open ("/dev/urandom", 0);
- if (fd != -1) {
- ssize_t size = read (fd, (char*)&__guard, sizeof(__guard));
- close (fd) ;
- if (size == sizeof(__guard)) return;
- }
- /* If a random generator can't be used, the protector switches the guard
- to the "terminator canary" */
- ((char*)__guard)[0] = 0; ((char*)__guard)[1] = 0;
- ((char*)__guard)[2] = '\n'; ((char*)__guard)[3] = 255;
+ int mib[2];
+ size_t len;
+
+ if (__guard[0] != 0)
+ return;
+
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_ARND;
+
+ len = sizeof(__guard);
+ if (__sysctl(mib, 2, __guard, &len, NULL, 0) == -1 ||
+ len != sizeof(__guard)) {
+ /* If sysctl was unsuccessful, use the "terminator canary". */
+ ((unsigned char *)__guard)[0] = 0;
+ ((unsigned char *)__guard)[1] = 0;
+ ((unsigned char *)__guard)[2] = '\n';
+ ((unsigned char *)__guard)[3] = 255;
+ }
}
+/*ARGSUSED*/
void
__stack_smash_handler(char func[], int damaged)
{
- const char message[] = "stack overflow in function %s";
- struct sigaction sa;
+ struct syslog_data sdata = SYSLOG_DATA_INIT;
+ const char message[] = "stack overflow in function %s";
+ struct sigaction sa;
+ sigset_t mask;
- /* this may fail on a chroot jail, though luck */
- syslog(LOG_CRIT, message, func);
+ /* Immediately block all signal handlers from running code */
+ sigfillset(&mask);
+ sigdelset(&mask, SIGABRT);
+ sigprocmask(SIG_BLOCK, &mask, NULL);
- bzero(&sa, sizeof(struct sigaction));
- sigemptyset(&sa.sa_mask);
- sa.sa_flags = 0;
- sa.sa_handler = SIG_DFL;
- sigaction(SIGABRT, &sa, NULL);
+ /* This may fail on a chroot jail... */
+ syslog_r(LOG_CRIT, &sdata, message, func);
- kill(getpid(), SIGABRT);
+ bzero(&sa, sizeof(struct sigaction));
+ sigemptyset(&sa.sa_mask);
+ sa.sa_flags = 0;
+ sa.sa_handler = SIG_DFL;
+ sigaction(SIGABRT, &sa, NULL);
- _exit(127);
+ kill(getpid(), SIGABRT);
+
+ _exit(127);
}