1#!/bin/sh 2 3# 4# Copyright (c) 2011 Peter Holm <pho@FreeBSD.org> 5# All rights reserved. 6# 7# Redistribution and use in source and binary forms, with or without 8# modification, are permitted provided that the following conditions 9# are met: 10# 1. Redistributions of source code must retain the above copyright 11# notice, this list of conditions and the following disclaimer. 12# 2. Redistributions in binary form must reproduce the above copyright 13# notice, this list of conditions and the following disclaimer in the 14# documentation and/or other materials provided with the distribution. 15# 16# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26# SUCH DAMAGE. 27# 28 29[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1 30 31# Cache inconsistency seen on "to" file for rename(2). 32 33# Scenario by jhb@ 34 35. ../default.cfg 36 37here=`pwd` 38cd /tmp 39sed '1,/^EOF/d' < $here/$0 > rename8.c 40mycc -o rename8 -Wall -Wextra -O2 rename8.c 41rm -f rename8.c 42cd $here 43 44mount | grep $mntpoint | grep -q /dev/md && umount -f $mntpoint 45mdconfig -l | grep -q md$mdstart && mdconfig -d -u $mdstart 46mdconfig -a -t swap -s 2g -u $mdstart 47bsdlabel -w md$mdstart auto 48newfs $newfs_flags md${mdstart}$part > /dev/null 49mount /dev/md${mdstart}$part $mntpoint 50chmod 777 $mntpoint 51 52su $testuser -c "cd $mntpoint; mkdir r; /tmp/rename8 r" 53ls -li $mntpoint/r | egrep -v "^total" 54 55for i in `jot 10`; do 56 mount | grep -q md${mdstart}$part && \ 57 umount $mntpoint && mdconfig -d -u $mdstart && break 58 sleep 1 59done 60if mount | grep -q md${mdstart}$part; then 61 fuser $mntpoint 62 echo "umount $mntpoint failed" 63 exit 1 64fi 65 66mdconfig -l | grep -q md$mdstart && 67 mdconfig -d -u $mdstart 68rm -f /tmp/rename8 69exit 70EOF 71#include <sys/types.h> 72#include <sys/stat.h> 73#include <err.h> 74#include <errno.h> 75#include <fcntl.h> 76#include <signal.h> 77#include <stdio.h> 78#include <stdlib.h> 79#include <sys/wait.h> 80#include <unistd.h> 81 82static char *always, *file1, *file2; 83static ino_t always_ino; 84 85static void 86usage(void) 87{ 88 fprintf(stderr, "Usage: rename_race <dir>\n"); 89 exit(1); 90} 91 92static void 93child(void) 94{ 95 struct stat sb; 96 97 /* Exit as soon as our parent exits. */ 98 while (getppid() != 1) { 99 stat(file1, &sb); 100 } 101 exit(0); 102} 103 104static void 105create_file(const char *path) 106{ 107 int fd; 108 109 fd = open(path, O_CREAT, 0666); 110 if (fd < 0) 111 err(1, "open(%s)", path); 112 close(fd); 113} 114 115int 116main(int ac, char **av) 117{ 118 struct stat sb, sb2; 119 pid_t pid; 120 int i, r; 121 122 if (ac != 2) 123 usage(); 124 if (stat(av[1], &sb) != 0) 125 err(1, "stat(%s)", av[1]); 126 if (!S_ISDIR(sb.st_mode)) 127 errx(1, "%s not a directory", av[1]); 128 129 asprintf(&always, "%s/file.always", av[1]); 130 asprintf(&file1, "%s/file1", av[1]); 131 asprintf(&file2, "%s/file2", av[1]); 132 133 create_file(always); 134 if (stat(always, &sb) != 0) 135 err(1, "stat(%s)", always); 136 always_ino = sb.st_ino; 137 138 pid = fork(); 139 if (pid < 0) 140 err(1, "fork"); 141 if (pid == 0) 142 child(); 143 r = 0; 144 for (i = 0; i < 100000; i++) { 145 if (unlink(file1) < 0 && errno != ENOENT) 146 err(1, "unlink(%s)", file1); 147 if (link(always, file1) < 0) 148 err(1, "link(%s, %s)", always, file1); 149 create_file(file2); 150 if (stat(file2, &sb2) < 0) 151 err(1, "stat(%s)", file2); 152 if (rename(file2, file1) < 0) 153 err(1, "rename(%s, %s)", file2, file1); 154 if (stat(file1, &sb) < 0) 155 err(1, "stat(%s)", file1); 156 if (sb.st_ino != sb2.st_ino || 157 sb.st_ino == always_ino) { 158 printf("FAIL. Bad stat: always: %ju file1: %ju (should be %ju)\n", 159 (uintmax_t)always_ino, (uintmax_t)sb.st_ino, 160 (uintmax_t)sb2.st_ino); 161 r = EXIT_FAILURE; 162 break; 163 } 164 } 165 kill(pid, SIGINT); 166 wait(NULL); 167 if (r == 0) { 168 unlink(always); 169 unlink(file1); 170 unlink(file2); 171 } 172 return (r); 173} 174