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 * 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 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); 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 } 105 106 ATF_TP_ADD_TCS(tp) 107 { 108 ATF_TP_ADD_TC(tp, unblock); 109 110 return (atf_no_error()); 111 } 112