accept_fd_leak.c revision 281974
1/*- 2 * Copyright (c) 2004 Robert N. M. Watson 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: stable/10/tools/regression/sockets/accept_fd_leak/accept_fd_leak.c 281974 2015-04-25 05:31:52Z ngie $ 27 */ 28 29#include <sys/param.h> 30#include <sys/socket.h> 31#include <sys/wait.h> 32 33#include <netinet/in.h> 34 35#include <err.h> 36#include <errno.h> 37#include <fcntl.h> 38#include <signal.h> 39#include <stdio.h> 40#include <stdlib.h> 41#include <string.h> 42#include <unistd.h> 43 44#define BIND_ATTEMPTS 10 45#define LOOPS 500 46#define NUM_ATTEMPTS 1000 47 48static volatile int quit; 49 50static void 51child_died(int sig __unused) 52{ 53 54 quit = 1; 55} 56 57/* 58 * This test is intended to detect a leak of a file descriptor in the process 59 * following a failed non-blocking accept. It measures an available fd 60 * baseline, then performs 1000 failing accepts, then checks to see what the 61 * next fd is. It relies on sequential fd allocation, and will test for it 62 * briefly before beginning (not 100% reliable, but a good start). 63 */ 64int 65main(void) 66{ 67 struct sockaddr_in sin; 68 socklen_t size; 69 pid_t child; 70 int fd1, fd2, fd3, i, listen_port, s, status; 71 72 printf("1..2\n"); 73 74 /* 75 * Check for sequential fd allocation, and give up early if not. 76 */ 77 fd1 = dup(STDIN_FILENO); 78 fd2 = dup(STDIN_FILENO); 79 if (fd2 != fd1 + 1) 80 errx(-1, "Non-sequential fd allocation\n"); 81 82 s = socket(PF_INET, SOCK_STREAM, 0); 83 if (s == -1) 84 errx(-1, "socket: %s", strerror(errno)); 85 86 bzero(&sin, sizeof(sin)); 87 sin.sin_len = sizeof(sin); 88 sin.sin_family = AF_INET; 89 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); 90 91 srandomdev(); 92 93 for (i = 0; i < BIND_ATTEMPTS; i++) { 94 /* Pick a random unprivileged port 1025-65535 */ 95 listen_port = MAX((int)random() % 65535, 1025); 96 sin.sin_port = htons(listen_port); 97 if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) == 0) 98 break; 99 warn("bind with %d failed", listen_port); 100 usleep(1000); 101 } 102 if (i >= BIND_ATTEMPTS) { 103 printf("Bail out!\n"); 104 exit(1); 105 } 106 107 if (listen(s, -1) != 0) 108 errx(-1, "listen: %s", strerror(errno)); 109 110 i = fcntl(s, F_GETFL); 111 if (i == -1) 112 errx(-1, "ioctl(F_GETFL): %s", strerror(errno)); 113 i |= O_NONBLOCK; 114 if (fcntl(s, F_SETFL, i) != 0) 115 errx(-1, "ioctl(F_SETFL): %s", strerror(errno)); 116 i = fcntl(s, F_GETFL); 117 if (i == -1) 118 errx(-1, "ioctl(F_GETFL): %s", strerror(errno)); 119 if ((i & O_NONBLOCK) != O_NONBLOCK) 120 errx(-1, "Failed to set O_NONBLOCK (i=0x%x)\n", i); 121 122 for (i = 0; i < LOOPS; i++) { 123 size = sizeof(sin); 124 if (accept(s, (struct sockaddr *)&sin, &size) != -1) 125 errx(-1, "accept succeeded\n"); 126 if (errno != EAGAIN) 127 errx(-1, "accept: %s", strerror(errno)); 128 } 129 130 /* 131 * Allocate a file descriptor and make sure it's fd2+2. 2 because 132 * we allocate an fd for the socket. 133 */ 134 fd3 = dup(STDIN_FILENO); 135 if (fd3 != fd2 + 2) 136 printf("not ok 1 - (%d, %d, %d)\n", fd1, fd2, fd3); 137 else 138 printf("ok 1\n"); 139 140 /* 141 * Try failing accept's w/o non-blocking where the destination 142 * address pointer is invalid. 143 */ 144 close(fd3); 145 signal(SIGCHLD, child_died); 146 child = fork(); 147 if (child < 0) 148 errx(-1, "fork: %s", strerror(errno)); 149 150 /* 151 * Child process does `NUM_ATTEMPTS` connects. 152 */ 153 if (child == 0) { 154 close(fd1); 155 close(fd2); 156 close(s); 157 158 bzero(&sin, sizeof(sin)); 159 sin.sin_len = sizeof(sin); 160 sin.sin_family = AF_INET; 161 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK); 162 sin.sin_port = htons(listen_port); 163 164 for (i = 0; i < NUM_ATTEMPTS; i++) { 165 s = socket(PF_INET, SOCK_STREAM, 0); 166 if (s == -1) 167 errx(-1, "socket: %s", strerror(errno)); 168 if (connect(s, (struct sockaddr *)&sin, 169 sizeof(sin)) < 0) 170 errx(-1, "connect: %s", strerror(errno)); 171 close(s); 172 } 173 _exit(0); 174 } 175 176 /* Reset back to a blocking socket. */ 177 i = fcntl(s, F_GETFL); 178 if (i == -1) 179 errx(-1, "ioctl(F_GETFL): %s", strerror(errno)); 180 i &= ~O_NONBLOCK; 181 if (fcntl(s, F_SETFL, i) != 0) 182 errx(-1, "ioctl(F_SETFL): %s", strerror(errno)); 183 i = fcntl(s, F_GETFL); 184 if (i == -1) 185 errx(-1, "ioctl(F_GETFL): %s", strerror(errno)); 186 if (i & O_NONBLOCK) 187 errx(-1, "Failed to clear O_NONBLOCK (i=0x%x)\n", i); 188 189 /* Do `NUM_ATTEMPTS` accepts with an invalid pointer. */ 190 for (i = 0; !quit && i < NUM_ATTEMPTS; i++) { 191 size = sizeof(sin); 192 if (accept(s, (struct sockaddr *)(uintptr_t)(0x100), 193 &size) != -1) 194 errx(-1, "accept succeeded\n"); 195 if (errno != EFAULT) 196 errx(-1, "accept: %s", strerror(errno)); 197 } 198 199 if (waitpid(child, &status, 0) < 0) 200 errx(-1, "waitpid: %s", strerror(errno)); 201 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) 202 warnx("child process died"); 203 204 /* 205 * Allocate a file descriptor and make sure it's fd2+2. 2 because 206 * we allocate an fd for the socket. 207 */ 208 fd3 = dup(STDIN_FILENO); 209 if (fd3 != fd2 + 2) 210 printf("not ok 2 - (%d, %d, %d)\n", fd1, fd2, fd3); 211 else 212 printf("ok 2\n"); 213 214 return (0); 215} 216