1 /*-
2 * Copyright (c) 2023 Klara, Inc.
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7 #include <sys/resource.h>
8 #include <sys/wait.h>
9
10 #include <errno.h>
11 #include <libutil.h>
12 #include <unistd.h>
13
14 #include <atf-c.h>
15
16 ATF_TC(forkfail);
ATF_TC_HEAD(forkfail,tc)17 ATF_TC_HEAD(forkfail, tc)
18 {
19 atf_tc_set_md_var(tc, "descr", "Check for fd leak when fork() fails");
20 atf_tc_set_md_var(tc, "require.user", "unprivileged");
21 }
22
ATF_TC_BODY(forkfail,tc)23 ATF_TC_BODY(forkfail, tc)
24 {
25 struct rlimit orl, nrl;
26 pid_t pid;
27 int prevfd, fd, pty;
28
29 /* set process limit to 1 so fork() will fail */
30 ATF_REQUIRE_EQ(0, getrlimit(RLIMIT_NPROC, &orl));
31 nrl = orl;
32 nrl.rlim_cur = 1;
33 ATF_REQUIRE_EQ(0, setrlimit(RLIMIT_NPROC, &nrl));
34 /* check first free fd */
35 ATF_REQUIRE((fd = dup(0)) > 0);
36 ATF_REQUIRE_EQ(0, close(fd));
37 /* attempt forkpty() */
38 pid = forkpty(&pty, NULL, NULL, NULL);
39 if (pid == 0) {
40 /* child - fork() unexpectedly succeeded */
41 _exit(0);
42 }
43 ATF_CHECK_ERRNO(EAGAIN, pid < 0);
44 if (pid > 0) {
45 /* parent - fork() unexpectedly succeeded */
46 (void)waitpid(pid, NULL, 0);
47 }
48 /* check that first free fd hasn't changed */
49 prevfd = fd;
50 ATF_REQUIRE((fd = dup(0)) > 0);
51 ATF_CHECK_EQ(prevfd, fd);
52 }
53
ATF_TP_ADD_TCS(tp)54 ATF_TP_ADD_TCS(tp)
55 {
56 ATF_TP_ADD_TC(tp, forkfail);
57 return (atf_no_error());
58 }
59