1 /*
2 *
3 * Copyright (c) International Business Machines Corp., 2001
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
13 * the GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 */
19
20 /*
21 * Test Name: munmap02
22 *
23 * Test Description:
24 * Verify that, munmap call will succeed to unmap a mapped file or
25 * anonymous shared memory region from the calling process's address space
26 * if the region specified by the address and the length is part or all of
27 * the mapped region.
28 *
29 * Expected Result:
30 * munmap call should succeed to unmap a part or all of mapped region of a
31 * file or anonymous shared memory from the process's address space and it
32 * returns with a value 0,
33 * further reference to the unmapped region should result in a segmentation
34 * fault (SIGSEGV).
35 *
36 * Algorithm:
37 * Setup:
38 * Setup signal handling.
39 * Create temporary directory.
40 * Pause for SIGUSR1 if option specified.
41 *
42 * Test:
43 * Loop if the proper options are given.
44 * Execute system call
45 * Check return code, if system call failed (return=-1)
46 * Log the errno and Issue a FAIL message.
47 * Otherwise,
48 * Verify the Functionality of system call
49 * if successful,
50 * Issue Functionality-Pass message.
51 * Otherwise,
52 * Issue Functionality-Fail message.
53 * Cleanup:
54 * Print errno log and/or timing stats if options given
55 * Delete the temporary directory created.
56 *
57 * Usage: <for command-line>
58 * munmap01 [-c n] [-f] [-i n] [-I x] [-P x] [-t]
59 * where, -c n : Run n copies concurrently.
60 * -f : Turn off functionality Testing.
61 * -i n : Execute test n times.
62 * -I x : Execute test for x seconds.
63 * -P x : Pause for x seconds between iterations.
64 * -t : Turn on syscall timing.
65 *
66 * HISTORY
67 * 07/2001 Ported by Wayne Boyer
68 *
69 * RESTRICTIONS:
70 * None.
71 */
72 #include <errno.h>
73 #include <unistd.h>
74 #include <fcntl.h>
75 #include <sys/stat.h>
76 #include <sys/mman.h>
77
78 #include "test.h"
79
80 #define TEMPFILE "mmapfile"
81
82 char *TCID = "munmap02";
83 int TST_TOTAL = 1;
84
85 static size_t page_sz;
86 char *addr; /* addr of memory mapped region */
87 int fildes; /* file descriptor for tempfile */
88 unsigned int map_len; /* length of the region to be mapped */
89
90 void setup(); /* Main setup function of test */
91 void cleanup(); /* cleanup function for the test */
92 void sig_handler(); /* signal catching function */
93
94 #ifndef UCLINUX
95
main(int ac,char ** av)96 int main(int ac, char **av)
97 {
98 int lc;
99
100 tst_parse_opts(ac, av, NULL, NULL);
101
102 for (lc = 0; TEST_LOOPING(lc); lc++) {
103
104 tst_count = 0;
105
106 setup();
107
108 /*
109 * Call munmap to unmap the part of the mapped region of the
110 * temporary file from the address and length that is part of
111 * the mapped region.
112 */
113 TEST(munmap(addr, map_len));
114
115 /* Check for the return value of munmap() */
116 if (TEST_RETURN == -1) {
117 tst_resm(TFAIL, "munmap() fails, errno=%d : %s",
118 TEST_ERRNO, strerror(TEST_ERRNO));
119 continue;
120 }
121 /*
122 * Check whether further reference is possible
123 * to the unmapped memory region by writing
124 * to the first byte of region with
125 * some arbitrary number.
126 */
127 *addr = 50;
128
129 /* This message is printed if no SIGSEGV */
130 tst_resm(TFAIL, "process succeeds to refer unmapped "
131 "memory region");
132 cleanup();
133
134 }
135 tst_exit();
136 }
137
138 #else
139
main(void)140 int main(void)
141 {
142 tst_resm(TINFO, "munmap02 test is not available on uClinux");
143 tst_exit();
144 }
145
146 #endif /* ifndef UCLINUX */
147
148 /*
149 * setup() - performs all ONE TIME setup for this test.
150 * Setup signal handler to catch SIGSEGV.
151 * Get system page size, create a temporary file for reading/writing,
152 * write one byte data into it, map the open file for the specified
153 * map length.
154 */
setup(void)155 void setup(void)
156 {
157
158 tst_sig(NOFORK, DEF_HANDLER, cleanup);
159
160 /* call signal function to trap the signal generated */
161 if (signal(SIGSEGV, sig_handler) == SIG_ERR) {
162 tst_brkm(TBROK, cleanup, "signal fails to catch signal");
163 }
164
165 TEST_PAUSE;
166
167 /* Get the system page size */
168 page_sz = getpagesize();
169
170 /*
171 * Get the length of the open file to be mapped into process
172 * address space.
173 */
174 map_len = 3 * page_sz;
175
176 tst_tmpdir();
177
178 /* Creat a temporary file used for mapping */
179 if ((fildes = open(TEMPFILE, O_RDWR | O_CREAT, 0666)) < 0) {
180 tst_brkm(TBROK, cleanup, "open() on %s Failed, errno=%d : %s",
181 TEMPFILE, errno, strerror(errno));
182 }
183
184 /*
185 * move the file pointer to maplength position from the beginning
186 * of the file.
187 */
188 if (lseek(fildes, map_len, SEEK_SET) == -1) {
189 tst_brkm(TBROK, cleanup, "lseek() fails on %s, errno=%d : %s",
190 TEMPFILE, errno, strerror(errno));
191 }
192
193 /* Write one byte into temporary file */
194 if (write(fildes, "a", 1) != 1) {
195 tst_brkm(TBROK, cleanup, "write() on %s Failed, errno=%d : %s",
196 TEMPFILE, errno, strerror(errno));
197 }
198
199 /*
200 * map the open file 'TEMPFILE' from its beginning up to the maplength
201 * into the calling process's address space at the system choosen
202 * with read/write permissions to the the mapped region.
203 */
204 #ifdef UCLINUX
205 /* mmap() doesn't support MAP_SHARED on uClinux */
206 addr = mmap(0, map_len, PROT_READ | PROT_WRITE,
207 MAP_FILE | MAP_PRIVATE, fildes, 0);
208 #else
209 addr = mmap(0, map_len, PROT_READ | PROT_WRITE,
210 MAP_FILE | MAP_SHARED, fildes, 0);
211 #endif
212
213 /* check for the return value of mmap system call */
214 if (addr == (char *)MAP_FAILED) {
215 tst_brkm(TBROK, cleanup, "mmap() Failed on %s, errno=%d : %s",
216 TEMPFILE, errno, strerror(errno));
217 }
218
219 /*
220 * increment the start address of the region at which the file is
221 * mapped to a maplength of 3 times the system page size by the value
222 * of system page size and decrement the maplength value by the value
223 * of system page size.
224 */
225 addr = (char *)((long)addr + page_sz);
226 map_len = map_len - page_sz;
227 }
228
229 /*
230 * void
231 * sig_handler() - signal catching function.
232 * This function is used to trap the signal generated when tried to read or
233 * write to the memory mapped region which is already detached from the
234 * calling process address space.
235 * this function is invoked when SIGSEGV generated and it calls test
236 * cleanup function and exit the program.
237 */
sig_handler(void)238 void sig_handler(void)
239 {
240 tst_resm(TPASS, "Functionality of munmap() successful");
241
242 /* Invoke test cleanup function and exit */
243 cleanup();
244
245 tst_exit();
246 }
247
248 /*
249 * cleanup() - performs all ONE TIME cleanup for this test at
250 * completion or premature exit.
251 * Unmap the portion of the region of the file left unmapped.
252 * Close the temporary file.
253 * Remove the temporary directory.
254 */
cleanup(void)255 void cleanup(void)
256 {
257
258 /*
259 * get the start address and length of the portion of
260 * the mapped region of the file.
261 */
262 addr = (char *)((long)addr - page_sz);
263 map_len = map_len - page_sz;
264
265 /* unmap the portion of the region of the file left unmapped */
266 if (munmap(addr, map_len) < 0) {
267 tst_brkm(TBROK, NULL,
268 "munmap() fails to unmap portion of mapped region");
269 }
270
271 /* Close the temporary file */
272 if (close(fildes) < 0) {
273 tst_brkm(TBROK, NULL, "close() on %s Failed, errno=%d : %s",
274 TEMPFILE, errno, strerror(errno));
275 }
276
277 tst_rmdir();
278 }
279