1 /*-
2 * Copyright (c) 2005 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
27 #include <err.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <limits.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35
36 /*
37 * This regression test attempts to exercise two instances of uprintf(9) in
38 * UFS: (1) when blocks are exhausted, and (2) when inodes are exhausted, in
39 * order to attempt to trigger races in the uprintf(9) code. The test
40 * accepts a pointer to a path -- ideally, a very small UFS partition -- and
41 * then proceeds to fill it in various ways.
42 *
43 * This tool assumes that it is alright to create, and delete, entries in the
44 * directory with names of integer values. Don't run this tool against a
45 * directory that has files with names along those lines if you want to keep
46 * the files.
47 *
48 * Suggested usage is:
49 *
50 * mdconfig -a -t malloc -s 512
51 * newfs /dev/mdX
52 * mount /dev/mdX /mnt
53 * ufs_uprintf /mnt
54 * umount /mnt
55 * mdconfig -d -u X
56 */
57
58 #define NUMTRIES 200
59
60 /*
61 * Fill up the disk, then generate NUMTRIES additional ENOSPC errors.
62 */
63 #define BLOCKSIZE 1024
64 #define BLOCKS_FILENAME "0"
65 static void
fill_blocks(void)66 fill_blocks(void)
67 {
68 char block[BLOCKSIZE];
69 ssize_t len;
70 int fd, i;
71
72 fd = open(BLOCKS_FILENAME, O_CREAT | O_TRUNC | O_RDWR, 0600);
73 if (fd < 0)
74 err(-1, "fill_blocks: open(%s)", BLOCKS_FILENAME);
75
76 /*
77 * First step: fill the disk device. Keep extending the file until
78 * we hit our first error, and hope it is ENOSPC.
79 */
80 bzero(block, BLOCKSIZE);
81 errno = 0;
82 while (1) {
83 len = write(fd, block, BLOCKSIZE);
84 if (len < 0)
85 break;
86 if (len != BLOCKSIZE) {
87 warnx("fill_blocks: write(%d) returned %zd",
88 BLOCKSIZE, len);
89 close(fd);
90 (void)unlink(BLOCKS_FILENAME);
91 exit(-1);
92 }
93
94 }
95 if (errno != ENOSPC) {
96 warn("fill_blocks: write");
97 close(fd);
98 (void)unlink(BLOCKS_FILENAME);
99 exit(-1);
100 }
101
102 /*
103 * Second step: generate NUMTRIES instances of the error by retrying
104 * the write.
105 */
106 for (i = 0; i < NUMTRIES; i++) {
107 len = write(fd, block, BLOCKSIZE);
108 if (len < 0 && errno != ENOSPC) {
109 warn("fill_blocks: write after ENOSPC");
110 close(fd);
111 (void)unlink(BLOCKS_FILENAME);
112 exit(-1);
113 }
114 }
115
116 close(fd);
117 (void)unlink(BLOCKS_FILENAME);
118 }
119
120 /*
121 * Create as many entries in the directory as we can, then once we start
122 * hitting ENOSPC, try NUMTRIES additional times. Note that we don't be able
123 * to tell the difference between running out of inodes and running out of
124 * room to extend the directory, so this is just a best effort.
125 */
126 static void
fill_inodes(void)127 fill_inodes(void)
128 {
129 char path[PATH_MAX];
130 int fd, i, max;
131
132 /*
133 * First step, fill the directory.
134 */
135 i = 0;
136 while (1) {
137 snprintf(path, PATH_MAX, "%d", i);
138 fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
139 if (fd < 0)
140 break;
141 close(fd);
142 i++;
143 }
144 max = i;
145 if (errno != ENOSPC) {
146 warn("fill_inodes: open(%s)", path);
147 goto teardown;
148 }
149
150 for (i = 0; i < NUMTRIES; i++) {
151 fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
152 if (fd < 0 && errno != ENOSPC) {
153 warn("fill_inodes: open(%s) after ENOSPC", path);
154 goto teardown;
155 }
156 if (fd >= 0) {
157 warnx("fill_inodes: open(%s) after ENOSPC returned "
158 " %d", path, fd);
159 close(fd);
160 goto teardown;
161 }
162 }
163
164 teardown:
165 for (i = 0; i < max; i++) {
166 snprintf(path, PATH_MAX, "%d", i);
167 (void)unlink(path);
168 }
169 }
170
171 int
main(int argc,char * argv[])172 main(int argc, char *argv[])
173 {
174
175 if (argc != 2)
176 err(-1, "usage: ufs_uprintf /non_optional_path");
177
178 if (chdir(argv[1]) < 0)
179 err(-1, "chdir(%s)", argv[1]);
180
181 fill_blocks();
182
183 fill_inodes();
184
185 return (0);
186 }
187