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|
#!/bin/sh
#
# SPDX-License-Identifier: BSD-2-Clause
#
# Copyright (c) 2022 Peter Holm <pho@FreeBSD.org>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
# SUCH DAMAGE.
#
# Fatal trap -4186856: UNKNOWN while in kernel mode
# cpuid = 1; apic id = 01
# error code = 0xfbafcf8c
# instruction pointer = 0x79e4:0x4
# stack pointer = 0x28:0xffc0aff0
# frame pointer = 0x28:0x204620d4
# code segment = base 0x0, limit 0x0, type 0x0
# = DPL 0, pres 0, def32 0, gran 0
# processor eflags = trace trap, at 0x3b/frame 0xffc0340c
# KDB: enter: panic
# [ thread pid 15631 tid 114622 ]
# Stopped at kdb_enter+0x34: movl $0,kdb_why
# db>
[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1
prog=sigreturn3
cat > /tmp/$prog.c <<EOF
#include <sys/types.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <libutil.h>
#include <pthread.h>
#include <pthread_np.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#define N 4096
#define RUNTIME 120
#define THREADS 1
static uint32_t r[N];
static void
hand(int i __unused) { /* handler */
exit(1);
}
static void *
churn(void *arg __unused)
{
time_t start;
pthread_set_name_np(pthread_self(), __func__);
start = time(NULL);
while (time(NULL) - start < 10) {
arc4random_buf(r, sizeof(r));
usleep(100);
}
return(NULL);
}
static void *
calls(void *arg __unused)
{
time_t start;
start = time(NULL);
while (time(NULL) - start < 10) {
arc4random_buf(r, sizeof(r));
alarm(1);
syscall(SYS_sigreturn, r);
}
return (NULL);
}
int
main(int argc, char **argv)
{
struct passwd *pw;
struct rlimit limit;
pid_t pid;
pthread_t rp, cp[THREADS];
time_t start;
int e, j;
if ((pw = getpwnam("nobody")) == NULL)
err(1, "failed to resolve nobody");
if (getenv("USE_ROOT") && argc == 2)
fprintf(stderr, "Running syscall4 as root for %s.\n",
argv[1]);
else {
if (setgroups(0, NULL) ||
setegid(pw->pw_gid) || setgid(pw->pw_gid) ||
seteuid(pw->pw_uid) || setuid(pw->pw_uid))
err(1, "Can't drop privileges to \"nobody\"");
endpwent();
}
limit.rlim_cur = limit.rlim_max = 1000;
#if defined(RLIMIT_NPTS)
if (setrlimit(RLIMIT_NPTS, &limit) < 0)
err(1, "setrlimit");
#endif
signal(SIGALRM, hand);
signal(SIGILL, hand);
signal(SIGFPE, hand);
signal(SIGSEGV, hand);
signal(SIGBUS, hand);
signal(SIGURG, hand);
signal(SIGSYS, hand);
signal(SIGTRAP, hand);
if (daemon(1, 1) == -1)
err(1, "daemon()");
start = time(NULL);
while ((time(NULL) - start) < RUNTIME) {
if ((pid = fork()) == 0) {
if ((e = pthread_create(&rp, NULL, churn, NULL)) != 0)
errc(1, e, "pthread_create");
for (j = 0; j < THREADS; j++)
if ((e = pthread_create(&cp[j], NULL, calls,
NULL)) != 0)
errc(1, e, "pthread_create");
for (j = 0; j < THREADS; j++)
pthread_join(cp[j], NULL);
if ((e = pthread_kill(rp, SIGINT)) != 0)
errc(1, e, "pthread_kill");
if ((e = pthread_join(rp, NULL)) != 0)
errc(1, e, "pthread_join");
_exit(0);
}
waitpid(pid, NULL, 0);
}
return (0);
}
EOF
cd /tmp
cc -o $prog -Wall -Wextra -O0 $prog.c -lpthread || exit 1
start=`date +%s`
while [ $((`date +%s` - start)) -lt 300 ]; do
./$prog > /dev/null 2>&1
done
rm -f /tmp/$prog /tmp/$prog.c /tmp/$prog.core
exit 0
|
