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/*-
* Copyright (c) 2010 Mikolaj Golub
* All rights reserved.
*
* 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.
*
* $FreeBSD$
*/
/*
* This regression test attempts to trigger a race that occurs when both
* endpoints of a connected UNIX domain socket are closed at once. The two
* close paths may run concurrently leading to a call to sodisconnect() on an
* already-closed socket in kernel. Before it was fixed, this might lead to
* ENOTCONN being returned improperly from close().
*
* This race is fairly timing-dependent, so it effectively requires SMP, and
* may not even trigger then.
*/
#include <sys/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdlib.h>
#include <stdio.h>
#include <strings.h>
#include <string.h>
#include <unistd.h>
#include <err.h>
static char socket_path[] = "tmp.XXXXXXXX";
#define USLEEP 100
#define LOOPS 100000
int
main(void)
{
struct sockaddr_un servaddr;
int listenfd, connfd, pid;
u_int counter, ncpus;
size_t len;
len = sizeof(ncpus);
if (sysctlbyname("kern.smp.cpus", &ncpus, &len, NULL, 0) < 0)
err(1, "kern.smp.cpus");
if (len != sizeof(ncpus))
errx(1, "kern.smp.cpus: invalid length");
if (ncpus < 2)
warnx("SMP not present, test may be unable to trigger race");
if (mkstemp(socket_path) == -1)
err(1, "mkstemp failed");
unlink(socket_path);
/*
* Create a UNIX domain socket that the child will repeatedly
* accept() from, and that the parent will repeatedly connect() to.
*/
if ((listenfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0)
err(1, "parent: socket error");
(void)unlink(socket_path);
bzero(&servaddr, sizeof(servaddr));
servaddr.sun_family = AF_LOCAL;
strcpy(servaddr.sun_path, socket_path);
if (bind(listenfd, (struct sockaddr *) &servaddr,
sizeof(servaddr)) < 0)
err(1, "parent: bind error");
if (listen(listenfd, 1024) < 0)
err(1, "parent: listen error");
pid = fork();
if (pid == -1)
err(1, "fork()");
if (pid != 0) {
/*
* In the parent, repeatedly connect and disconnect from the
* socket, attempting to induce the race.
*/
close(listenfd);
sleep(1);
bzero(&servaddr, sizeof(servaddr));
servaddr.sun_family = AF_LOCAL;
strcpy(servaddr.sun_path, socket_path);
for (counter = 0; counter < LOOPS; counter++) {
if ((connfd = socket(AF_LOCAL, SOCK_STREAM, 0)) < 0) {
(void)kill(pid, SIGTERM);
err(1, "parent: socket error");
}
if (connect(connfd, (struct sockaddr *)&servaddr,
sizeof(servaddr)) < 0) {
(void)kill(pid, SIGTERM);
err(1, "parent: connect error");
}
if (close(connfd) < 0) {
(void)kill(pid, SIGTERM);
err(1, "parent: close error");
}
usleep(USLEEP);
}
(void)kill(pid, SIGTERM);
} else {
/*
* In the child, loop accepting and closing. We may pick up
* the race here so report errors from close().
*/
for ( ; ; ) {
if ((connfd = accept(listenfd,
(struct sockaddr *)NULL, NULL)) < 0)
err(1, "child: accept error");
if (close(connfd) < 0)
err(1, "child: close error");
}
}
printf("OK\n");
exit(0);
}
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