freebsd-dev/tests/sys/kern/kern_descrip_test.c
Eric van Gyzen 4661f8af40 Fix problems in the kern_maxfiles__increase test
ATF functions such as ATF_REQUIRE do not work correctly in child processes.
Use plain C functions to report errors instead.

In the parent, check for the untimely demise of children.  Without this,
the test hung until the framework's timeout.

Raise the resource limit on the number of open files.  If this was too low,
the test hit the two problems above.

Restore the kern.maxfiles sysctl OID in the cleanup function.
The body prematurely removed the symlink in which the old value was saved.

Make the test more robust by opening more files.  In fact, due to the
integer division by 4, this was necessary to make the test valid with
some initial values of maxfiles.  Thanks, asomers@.

wait() for children instead of sleeping.

Clean up a temporary file created by the test ("afile").

Reviewed by:	asomers
MFC after:	1 week
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D21900
2019-10-08 13:43:05 +00:00

213 lines
5.4 KiB
C

/*-
* Copyright (c) 2014 EMC Corp.
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/limits.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include <unistd.h>
#include <atf-c.h>
static volatile sig_atomic_t done;
#define AFILE "afile"
#define EXPANDBY 1000
#define PARALLEL 4
#define RENDEZVOUS "rendezvous"
#define VALUE "value"
ATF_TC_WITHOUT_HEAD(dup2__simple);
ATF_TC_BODY(dup2__simple, tc)
{
int fd1, fd2;
struct stat sb1, sb2;
ATF_REQUIRE((fd1 = open(AFILE, O_CREAT, 0644)) != -1);
fd2 = 27;
ATF_REQUIRE(dup2(fd1, fd2) != -1);
ATF_REQUIRE(fstat(fd1, &sb1) != -1);
ATF_REQUIRE(fstat(fd2, &sb2) != -1);
ATF_REQUIRE(bcmp(&sb1, &sb2, sizeof(sb1)) == 0);
}
ATF_TC(dup2__ebadf_when_2nd_arg_out_of_range);
ATF_TC_HEAD(dup2__ebadf_when_2nd_arg_out_of_range, tc)
{
atf_tc_set_md_var(tc, "descr", "Regression test for r234131");
}
ATF_TC_BODY(dup2__ebadf_when_2nd_arg_out_of_range, tc)
{
int fd1, fd2, ret;
ATF_REQUIRE((fd1 = open(AFILE, O_CREAT, 0644)) != -1);
fd2 = INT_MAX;
ret = dup2(fd1, fd2);
ATF_CHECK_EQ(-1, ret);
ATF_CHECK_EQ(EBADF, errno);
}
static void
handler(int s __unused)
{
done++;
}
static void
openfiles2(size_t n)
{
size_t i;
int r;
errno = 0;
for (i = 0; i < n; i++) {
r = open(AFILE, O_RDONLY);
if (r < 0) {
fprintf(stderr, "open: %s\n", strerror(errno));
_exit(1);
}
}
kill(getppid(), SIGUSR1);
for (;;) {
if (access(RENDEZVOUS, R_OK) != 0)
break;
usleep(1000);
}
_exit(0);
}
static void
openfiles(size_t n)
{
int i, fd;
signal(SIGUSR1, handler);
ATF_REQUIRE((fd = open(AFILE, O_CREAT, 0644)) != -1);
close(fd);
ATF_REQUIRE((fd = open(RENDEZVOUS, O_CREAT, 0644)) != -1);
close(fd);
done = 0;
for (i = 0; i < PARALLEL; i++)
if (fork() == 0)
openfiles2(n / PARALLEL);
while (done != PARALLEL) {
usleep(1000);
ATF_REQUIRE_EQ_MSG(0, waitpid(-1, NULL, WNOHANG),
"a child exited unexpectedly");
}
unlink(RENDEZVOUS);
for (i = 0; i < PARALLEL; i++)
ATF_CHECK_MSG(wait(NULL) > 0, "wait: %s", strerror(errno));
}
ATF_TC_WITH_CLEANUP(kern_maxfiles__increase);
ATF_TC_HEAD(kern_maxfiles__increase, tc)
{
atf_tc_set_md_var(tc, "require.user", "root");
atf_tc_set_md_var(tc, "require.config", "allow_sysctl_side_effects");
atf_tc_set_md_var(tc, "descr",
"Check kern.maxfiles expansion");
}
ATF_TC_BODY(kern_maxfiles__increase, tc)
{
size_t oldlen;
int maxfiles, oldmaxfiles, current;
char buf[80];
struct rlimit rl;
oldlen = sizeof(maxfiles);
if (sysctlbyname("kern.maxfiles", &maxfiles, &oldlen, NULL, 0) == -1)
atf_tc_fail("getsysctlbyname(%s): %s", "kern.maxfiles",
strerror(errno));
if (sysctlbyname("kern.openfiles", &current, &oldlen, NULL, 0) == -1)
atf_tc_fail("getsysctlbyname(%s): %s", "kern.openfiles",
strerror(errno));
oldmaxfiles = maxfiles;
/* Store old kern.maxfiles in a symlink for cleanup */
snprintf(buf, sizeof(buf), "%d", oldmaxfiles);
if (symlink(buf, VALUE) == 1)
atf_tc_fail("symlink(%s, %s): %s", buf, VALUE,
strerror(errno));
maxfiles += EXPANDBY;
if (sysctlbyname("kern.maxfiles", NULL, 0, &maxfiles, oldlen) == -1)
atf_tc_fail("getsysctlbyname(%s): %s", "kern.maxfiles",
strerror(errno));
rl.rlim_cur = rl.rlim_max = maxfiles;
ATF_REQUIRE_EQ_MSG(0, setrlimit(RLIMIT_NOFILE, &rl),
"setrlimit(RLIMIT_NOFILE, %d): %s", maxfiles, strerror(errno));
openfiles(oldmaxfiles - current + EXPANDBY / 2);
}
ATF_TC_CLEANUP(kern_maxfiles__increase, tc)
{
size_t oldlen;
int n, oldmaxfiles;
char buf[80];
if ((n = readlink(VALUE, buf, sizeof(buf))) > 0) {
buf[MIN((size_t)n, sizeof(buf) - 1)] = '\0';
if (sscanf(buf, "%d", &oldmaxfiles) == 1) {
oldlen = sizeof(oldmaxfiles);
(void) sysctlbyname("kern.maxfiles", NULL, 0,
&oldmaxfiles, oldlen);
}
}
(void)unlink(VALUE);
(void)unlink(AFILE);
}
ATF_TP_ADD_TCS(tp)
{
ATF_TP_ADD_TC(tp, dup2__simple);
ATF_TP_ADD_TC(tp, dup2__ebadf_when_2nd_arg_out_of_range);
ATF_TP_ADD_TC(tp, kern_maxfiles__increase);
return (atf_no_error());
}