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 47newfs $newfs_flags md$mdstart > /dev/null 48mount /dev/md$mdstart $mntpoint 49chmod 777 $mntpoint 50 51su $testuser -c "cd $mntpoint; mkdir r; /tmp/rename8 r" 52ls -li $mntpoint/r | egrep -v "^total" 53 54for i in `jot 10`; do 55 mount | grep -q md$mdstart && \ 56 umount $mntpoint && mdconfig -d -u $mdstart && break 57 sleep 1 58done 59if mount | grep -q md$mdstart; then 60 fuser $mntpoint 61 echo "umount $mntpoint failed" 62 exit 1 63fi 64 65mdconfig -l | grep -q md$mdstart && 66 mdconfig -d -u $mdstart 67rm -f /tmp/rename8 68exit 69EOF 70#include <sys/types.h> 71#include <sys/stat.h> 72#include <err.h> 73#include <errno.h> 74#include <fcntl.h> 75#include <signal.h> 76#include <stdio.h> 77#include <stdlib.h> 78#include <sys/wait.h> 79#include <unistd.h> 80 81static char *always, *file1, *file2; 82static ino_t always_ino; 83 84static void 85usage(void) 86{ 87 fprintf(stderr, "Usage: rename_race <dir>\n"); 88 exit(1); 89} 90 91static void 92child(void) 93{ 94 struct stat sb; 95 96 /* Exit as soon as our parent exits. */ 97 while (getppid() != 1) { 98 stat(file1, &sb); 99 } 100 exit(0); 101} 102 103static void 104create_file(const char *path) 105{ 106 int fd; 107 108 fd = open(path, O_CREAT, 0666); 109 if (fd < 0) 110 err(1, "open(%s)", path); 111 close(fd); 112} 113 114int 115main(int ac, char **av) 116{ 117 struct stat sb, sb2; 118 pid_t pid; 119 int i, r; 120 121 if (ac != 2) 122 usage(); 123 if (stat(av[1], &sb) != 0) 124 err(1, "stat(%s)", av[1]); 125 if (!S_ISDIR(sb.st_mode)) 126 errx(1, "%s not a directory", av[1]); 127 128 asprintf(&always, "%s/file.always", av[1]); 129 asprintf(&file1, "%s/file1", av[1]); 130 asprintf(&file2, "%s/file2", av[1]); 131 132 create_file(always); 133 if (stat(always, &sb) != 0) 134 err(1, "stat(%s)", always); 135 always_ino = sb.st_ino; 136 137 pid = fork(); 138 if (pid < 0) 139 err(1, "fork"); 140 if (pid == 0) 141 child(); 142 r = 0; 143 for (i = 0; i < 100000; i++) { 144 if (unlink(file1) < 0 && errno != ENOENT) 145 err(1, "unlink(%s)", file1); 146 if (link(always, file1) < 0) 147 err(1, "link(%s, %s)", always, file1); 148 create_file(file2); 149 if (stat(file2, &sb2) < 0) 150 err(1, "stat(%s)", file2); 151 if (rename(file2, file1) < 0) 152 err(1, "rename(%s, %s)", file2, file1); 153 if (stat(file1, &sb) < 0) 154 err(1, "stat(%s)", file1); 155 if (sb.st_ino != sb2.st_ino || 156 sb.st_ino == always_ino) { 157 printf("FAIL. Bad stat: always: %ju file1: %ju (should be %ju)\n", 158 (uintmax_t)always_ino, (uintmax_t)sb.st_ino, 159 (uintmax_t)sb2.st_ino); 160 r = EXIT_FAILURE; 161 break; 162 } 163 } 164 kill(pid, SIGINT); 165 wait(NULL); 166 if (r == 0) { 167 unlink(always); 168 unlink(file1); 169 unlink(file2); 170 } 171 return (r); 172} 173