1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2024 Gleb Smirnoff <glebius@FreeBSD.org>
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include <sys/socket.h>
29 #include <sys/un.h>
30 #include <assert.h>
31 #include <errno.h>
32 #include <pthread.h>
33 #include <unistd.h>
34 #include <netinet/in.h>
35
36 #include <atf-c.h>
37
38 /*
39 * shutdown(2) on SOCK_DGRAM shall return ENOTCONN per POSIX. However, there
40 * is historical behavior of the shutdown(2) also unblocking any ongoing
41 * recv(2) syscall on the socket. It is known that some programs rely on this
42 * behavior, but exact list of programs isn't known. Neither we know if the
43 * "feature" is required on PF_UNIX sockets or on PF_INET/INET6 sockets or
44 * on both kinds. Feel free to improve this comment if you know any details.
45 *
46 * List of relevant commits, bug reports and reviews:
47 * 63649db04205
48 * https://reviews.freebsd.org/D10351
49 * b114aa79596c (regresses)
50 * https://reviews.freebsd.org/D3039 (regresses)
51 * kern/84761 c5cff17017f9 aada5cccd878
52 */
53
54
55 static void *
blocking_thread(void * arg)56 blocking_thread(void *arg)
57 {
58 int *s = arg;
59 char buf[1];
60 int error, rv;
61
62 rv = recv(*s, buf, sizeof(buf), 0);
63 error = (rv == -1) ? errno : 0;
64
65 return ((void *)(uintptr_t)error);
66 }
67
68 static void
shutdown_thread(int s)69 shutdown_thread(int s)
70 {
71 pthread_t t;
72 int rv;
73
74 ATF_REQUIRE(pthread_create(&t, NULL, blocking_thread, &s) == 0);
75 usleep(1000);
76 ATF_REQUIRE(shutdown(s, SHUT_RD) == -1);
77 ATF_REQUIRE(errno == ENOTCONN);
78 ATF_REQUIRE(pthread_join(t, (void *)&rv) == 0);
79 ATF_REQUIRE(rv == 0);
80 close(s);
81 }
82
83 ATF_TC_WITHOUT_HEAD(unblock);
ATF_TC_BODY(unblock,tc)84 ATF_TC_BODY(unblock, tc)
85 {
86 static const struct sockaddr_un sun = {
87 .sun_family = AF_LOCAL,
88 .sun_len = sizeof(sun),
89 .sun_path = "shutdown-dgram-test-sock",
90 };
91 int s;
92
93 ATF_REQUIRE((s = socket(PF_UNIX, SOCK_DGRAM, 0)) >= 0);
94 ATF_REQUIRE(bind(s, (struct sockaddr *)&sun, sizeof(sun)) == 0);
95 shutdown_thread(s);
96
97 static const struct sockaddr_in sin = {
98 .sin_family = AF_INET,
99 .sin_len = sizeof(sin),
100 };
101 ATF_REQUIRE((s = socket(PF_INET, SOCK_DGRAM, 0)) >= 0);
102 ATF_REQUIRE(bind(s, (struct sockaddr *)&sin, sizeof(sin)) == 0);
103 shutdown_thread(s);
104 }
105
ATF_TP_ADD_TCS(tp)106 ATF_TP_ADD_TCS(tp)
107 {
108 ATF_TP_ADD_TC(tp, unblock);
109
110 return (atf_no_error());
111 }
112