1 /*
2 * Copyright (c) Wipro Technologies Ltd, 2002. All Rights Reserved.
3 * Copyright (c) 2012 Wanlong Gao <gaowanlong@cn.fujitsu.com>
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of version 2 of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
12 *
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16 *
17 */
18 /*
19 * TEST1
20 * -----
21 * Call clone() with all resources shared.
22 *
23 * CHILD:
24 * modify the shared resources
25 * return 1 on success
26 * PARENT:
27 * wait for child to finish
28 * verify that the shared resourses are modified
29 * return 1 on success
30 * If parent & child returns successfully
31 * test passed
32 * else
33 * test failed
34 *
35 * TEST2
36 * -----
37 * Call clone() with no resources shared.
38 *
39 * CHILD:
40 * modify the resources in child's address space
41 * return 1 on success
42 * PARENT:
43 * wait for child to finish
44 * verify that the parent's resourses are not modified
45 * return 1 on success
46 * If parent & child returns successfully
47 * test passed
48 * else
49 * test failed
50 */
51
52 #if defined UCLINUX && !__THROW
53 /* workaround for libc bug */
54 #define __THROW
55 #endif
56
57 #define _GNU_SOURCE
58
59 #include <errno.h>
60 #include <fcntl.h>
61 #include <sys/wait.h>
62 #include <sys/types.h>
63 #include <sys/syscall.h>
64 #include <sched.h>
65 #include "test.h"
66 #include "safe_macros.h"
67
68 #define FLAG_ALL (CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|SIGCHLD)
69 #define FLAG_NONE SIGCHLD
70 #define PARENT_VALUE 1
71 #define CHILD_VALUE 2
72 #define TRUE 1
73 #define FALSE 0
74
75 #include "clone_platform.h"
76
77 static void setup(void);
78 static int test_setup(void);
79 static void cleanup(void);
80 static void test_cleanup(void);
81 static int child_fn();
82 static int parent_test1(void);
83 static int parent_test2(void);
84 static int test_VM(void);
85 static int test_FS(void);
86 static int test_FILES(void);
87 static int test_SIG(void);
88 static int modified_VM(void);
89 static int modified_FS(void);
90 static int modified_FILES(void);
91 static int modified_SIG(void);
92 static void sig_child_defined_handler(int);
93 static void sig_default_handler();
94
95 static int fd_parent;
96 static char file_name[25];
97 static int parent_variable;
98 static char cwd_parent[FILENAME_MAX];
99 static int parent_got_signal, child_pid;
100
101 char *TCID = "clone02";
102
103 struct test_case_t {
104 int flags;
105 int (*parent_fn) ();
106 } test_cases[] = {
107 {
108 FLAG_ALL, parent_test1}, {
109 FLAG_NONE, parent_test2}
110 };
111
112 int TST_TOTAL = sizeof(test_cases) / sizeof(test_cases[0]);
113
main(int ac,char ** av)114 int main(int ac, char **av)
115 {
116
117 int lc;
118 void *child_stack;
119 int status, i;
120
121 tst_parse_opts(ac, av, NULL, NULL);
122
123 setup();
124
125 child_stack = malloc(CHILD_STACK_SIZE);
126 if (child_stack == NULL)
127 tst_brkm(TBROK, cleanup, "Cannot allocate stack for child");
128
129 for (lc = 0; TEST_LOOPING(lc); lc++) {
130 tst_count = 0;
131
132 for (i = 0; i < TST_TOTAL; ++i) {
133 if (test_setup() != 0) {
134 tst_resm(TWARN, "test_setup() failed, skipping this test case");
135 continue;
136 }
137
138 /* Test the system call */
139 TEST(ltp_clone(test_cases[i].flags, child_fn, NULL,
140 CHILD_STACK_SIZE, child_stack));
141
142 /* check return code */
143 if (TEST_RETURN == -1) {
144 tst_resm(TFAIL | TTERRNO, "clone() failed");
145 /* Cleanup & continue with next test case */
146 test_cleanup();
147 continue;
148 }
149
150 /* Wait for child to finish */
151 if ((wait(&status)) == -1) {
152 tst_resm(TWARN | TERRNO,
153 "wait failed; skipping testcase");
154 /* Cleanup & continue with next test case */
155 test_cleanup();
156 continue;
157 }
158
159 if (WTERMSIG(status))
160 tst_resm(TWARN, "child exitied with signal %d",
161 WTERMSIG(status));
162
163 /*
164 * Check the return value from child function and
165 * parent function. If both functions returned
166 * successfully, test passed, else failed
167 */
168 if (WIFEXITED(status) && WEXITSTATUS(status) == 0 &&
169 test_cases[i].parent_fn())
170 tst_resm(TPASS, "Test Passed");
171 else
172 tst_resm(TFAIL, "Test Failed");
173
174 /* Do test specific cleanup */
175 test_cleanup();
176 }
177 }
178
179 free(child_stack);
180
181 cleanup();
182 tst_exit();
183 }
184
setup(void)185 static void setup(void)
186 {
187 tst_sig(FORK, DEF_HANDLER, cleanup);
188 TEST_PAUSE;
189 tst_tmpdir();
190
191 /* Get unique file name for each child process */
192 if ((sprintf(file_name, "parent_file_%ld", syscall(__NR_gettid))) <= 0)
193 tst_brkm(TBROK | TERRNO, cleanup, "sprintf() failed");
194 }
195
cleanup(void)196 static void cleanup(void)
197 {
198 if (unlink(file_name) == -1)
199 tst_resm(TWARN | TERRNO, "unlink(%s) failed", file_name);
200 tst_rmdir();
201 }
202
test_setup(void)203 static int test_setup(void)
204 {
205
206 struct sigaction def_act;
207
208 /* Save current working directory of parent */
209 if (getcwd(cwd_parent, sizeof(cwd_parent)) == NULL) {
210 tst_resm(TWARN | TERRNO, "getcwd() failed in test_setup()");
211 return -1;
212 }
213
214 /*
215 * Set value for parent_variable in parent, which will be
216 * changed by child in test_VM(), for testing CLONE_VM flag
217 */
218 parent_variable = PARENT_VALUE;
219
220 /*
221 * Open file from parent, which will be closed by
222 * child in test_FILES(), used for testing CLONE_FILES flag
223 */
224 fd_parent = open(file_name, O_CREAT | O_RDWR, 0777);
225 if (fd_parent == -1) {
226 tst_resm(TWARN | TERRNO, "open() failed in test_setup()");
227 return -1;
228 }
229
230 /*
231 * set parent_got_signal to FALSE, used for testing
232 * CLONE_SIGHAND flag
233 */
234 parent_got_signal = FALSE;
235
236 /* Setup signal handler for SIGUSR2 */
237 def_act.sa_handler = sig_default_handler;
238 def_act.sa_flags = SA_RESTART;
239 sigemptyset(&def_act.sa_mask);
240
241 if (sigaction(SIGUSR2, &def_act, NULL) == -1) {
242 tst_resm(TWARN | TERRNO, "sigaction() failed in test_setup()");
243 return -1;
244 }
245
246 return 0;
247 }
248
test_cleanup(void)249 static void test_cleanup(void)
250 {
251
252 /* Restore parent's working directory */
253 SAFE_CHDIR(cleanup, cwd_parent);
254
255 }
256
child_fn(void)257 static int child_fn(void)
258 {
259
260 /* save child pid */
261 child_pid = syscall(__NR_gettid);
262
263 if (test_VM() == 0 && test_FILES() == 0 && test_FS() == 0 &&
264 test_SIG() == 0)
265 _exit(0);
266 _exit(1);
267 }
268
parent_test1(void)269 static int parent_test1(void)
270 {
271
272 /*
273 * For first test case (with all flags set), all resources are
274 * shared between parent and child. So whatever changes made by
275 * child should get reflected in parent also. modified_*()
276 * functions check this. All of them should return 1 for
277 * parent_test1() to return 1
278 */
279
280 if (modified_VM() && modified_FILES() && modified_FS() &&
281 modified_SIG())
282 return 0;
283 return -1;
284 }
285
parent_test2(void)286 static int parent_test2(void)
287 {
288
289 /*
290 * For second test case (with no resouce shared), all of the
291 * modified_*() functions should return 0 for parent_test2()
292 * to return 1
293 */
294 if (modified_VM() || modified_FILES() || modified_FS() ||
295 modified_SIG())
296 return 0;
297
298 return -1;
299 }
300
301 /*
302 * test_VM() - function to change parent_variable from child's
303 * address space. If CLONE_VM flag is set, child shares
304 * the memory space with parent so this will be visible
305 * to parent also.
306 */
307
test_VM(void)308 static int test_VM(void)
309 {
310 parent_variable = CHILD_VALUE;
311 return 0;
312 }
313
314 /*
315 * test_FILES() - This function closes a file descriptor opened by
316 * parent. If CLONE_FILES flag is set, the parent and
317 * the child process share the same file descriptor
318 * table. so this affects the parent also
319 */
test_FILES(void)320 static int test_FILES(void)
321 {
322 if (close(fd_parent) == -1) {
323 tst_resm(TWARN | TERRNO, "close failed in test_FILES");
324 return -1;
325 }
326 return 0;
327 }
328
329 /*
330 * test_FS() - This function changes the current working directory
331 * of the child process. If CLONE_FS flag is set, this
332 * will be visible to parent also.
333 */
test_FS(void)334 static int test_FS(void)
335 {
336 char *test_tmpdir;
337 int rval;
338
339 test_tmpdir = tst_get_tmpdir();
340 if (test_tmpdir == NULL) {
341 tst_resm(TWARN | TERRNO, "tst_get_tmpdir failed");
342 rval = -1;
343 } else if (chdir(test_tmpdir) == -1) {
344 tst_resm(TWARN | TERRNO, "chdir failed in test_FS");
345 rval = -1;
346 } else {
347 rval = 0;
348 }
349
350 free(test_tmpdir);
351 return rval;
352 }
353
354 /*
355 * test_SIG() - This function changes the signal handler for SIGUSR2
356 * signal for child. If CLONE_SIGHAND flag is set, this
357 * affects parent also.
358 */
test_SIG(void)359 static int test_SIG(void)
360 {
361
362 struct sigaction new_act;
363
364 new_act.sa_handler = sig_child_defined_handler;
365 new_act.sa_flags = SA_RESTART;
366 sigemptyset(&new_act.sa_mask);
367
368 /* Set signal handler to sig_child_defined_handler */
369 if (sigaction(SIGUSR2, &new_act, NULL) == -1) {
370 tst_resm(TWARN | TERRNO, "signal failed in test_SIG");
371 return -1;
372 }
373
374 /* Send SIGUSR2 signal to parent */
375 if (kill(getppid(), SIGUSR2) == -1) {
376 tst_resm(TWARN | TERRNO, "kill failed in test_SIG");
377 return -1;
378 }
379
380 return 0;
381 }
382
383 /*
384 * modified_VM() - This function is called by parent process to check
385 * whether child's modification to parent_variable
386 * is visible to parent
387 */
388
modified_VM(void)389 static int modified_VM(void)
390 {
391
392 if (parent_variable == CHILD_VALUE)
393 /* child has modified parent_variable */
394 return 1;
395
396 return 0;
397 }
398
399 /*
400 * modified_FILES() - This function checks for file descriptor table
401 * modifications done by child
402 */
modified_FILES(void)403 static int modified_FILES(void)
404 {
405 char buff[20];
406
407 if (((read(fd_parent, buff, sizeof(buff))) == -1) && (errno == EBADF))
408 /* Child has closed this file descriptor */
409 return 1;
410
411 /* close fd_parent */
412 if ((close(fd_parent)) == -1)
413 tst_resm(TWARN | TERRNO, "close() failed in modified_FILES()");
414
415 return 0;
416 }
417
418 /*
419 * modified_FS() - This function checks parent's current working directory
420 * to see whether its modified by child or not.
421 */
modified_FS(void)422 static int modified_FS(void)
423 {
424 char cwd[FILENAME_MAX];
425
426 if ((getcwd(cwd, sizeof(cwd))) == NULL)
427 tst_resm(TWARN | TERRNO, "getcwd() failed");
428
429 if (!(strcmp(cwd, cwd_parent)))
430 /* cwd hasn't changed */
431 return 0;
432
433 return 1;
434 }
435
436 /*
437 * modified_SIG() - This function checks whether child has changed
438 * parent's signal handler for signal, SIGUSR2
439 */
modified_SIG(void)440 static int modified_SIG(void)
441 {
442
443 if (parent_got_signal)
444 /*
445 * parent came through sig_child_defined_handler()
446 * this means child has changed parent's handler
447 */
448 return 1;
449
450 return 0;
451 }
452
453 /*
454 * sig_child_defined_handler() - Signal handler installed by child
455 */
sig_child_defined_handler(int pid)456 static void sig_child_defined_handler(int pid)
457 {
458 if ((syscall(__NR_gettid)) == child_pid)
459 /* Child got signal, give warning */
460 tst_resm(TWARN, "Child got SIGUSR2 signal");
461 else
462 parent_got_signal = TRUE;
463 }
464
465 /* sig_default_handler() - Default handler for parent */
sig_default_handler(void)466 static void sig_default_handler(void)
467 {
468 }
469