1 /*
2 * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 /* This code tests the fact that we actually remove stack guard page when calling
26 * JavaThread::exit() i.e. when detaching from current thread.
27 * We overflow the stack and check that we get access error because of a guard page.
28 * Than we detach from vm thread and overflow stack once again. This time we shouldn't
29 * get access error because stack guard page is removed
30 *
31 * Notice: due a complicated interaction of signal handlers, the test may crash.
32 * It's OK - don't file a bug.
33 */
34
35 #include <assert.h>
36 #include <jni.h>
37 #include <alloca.h>
38 #include <signal.h>
39 #include <sys/mman.h>
40 #include <stdlib.h>
41 #include <sys/ucontext.h>
42 #include <setjmp.h>
43 #include <unistd.h>
44 #include <sys/syscall.h>
45 #include <errno.h>
46
47 #include <pthread.h>
48
49 JavaVM* _jvm;
50
51 static jmp_buf context;
52
53 static int _last_si_code = -1;
54 static int _failures = 0;
55 static int _rec_count = 0;
56 static int _kp_rec_count = 0;
57
58 pid_t gettid() {
59 return (pid_t) syscall(SYS_gettid);
60 }
61
62 static void handler(int sig, siginfo_t *si, void *unused) {
63 _last_si_code = si->si_code;
64 printf("Got SIGSEGV(%d) at address: 0x%lx\n",si->si_code, (long) si->si_addr);
65 longjmp(context, 1);
66 }
67
68 void set_signal_handler() {
69 static char altstack[SIGSTKSZ];
70
71 stack_t ss = {
72 .ss_size = SIGSTKSZ,
73 .ss_flags = 0,
74 .ss_sp = altstack
75 };
76
77 struct sigaction sa = {
78 .sa_sigaction = handler,
79 .sa_flags = SA_ONSTACK | SA_SIGINFO | SA_RESETHAND
80 };
81
82 _last_si_code = -1;
83
84 sigaltstack(&ss, 0);
85 sigemptyset(&sa.sa_mask);
86 if (sigaction(SIGSEGV, &sa, NULL) == -1) {
87 fprintf(stderr, "Test ERROR. Can't set sigaction (%d)\n", errno);
88 exit(7);
89 }
90 }
91
92 void *run_java_overflow (void *p) {
93 JNIEnv *env;
94 jclass class_id;
95 jmethodID method_id;
96 int res;
97
98 res = (*_jvm)->AttachCurrentThread(_jvm, (void**)&env, NULL);
99 if (res != JNI_OK) {
100 fprintf(stderr, "Test ERROR. Can't attach to current thread\n");
101 exit(7);
102 }
103
104 class_id = (*env)->FindClass (env, "DoOverflow");
105 if (class_id == NULL) {
106 fprintf(stderr, "Test ERROR. Can't load class DoOverflow\n");
107 exit(7);
108 }
109
110 method_id = (*env)->GetStaticMethodID(env, class_id, "printIt", "()V");
111 if (method_id == NULL) {
112 fprintf(stderr, "Test ERROR. Can't find method DoOverflow.printIt\n");
113 exit(7);
114 }
115
116 (*env)->CallStaticVoidMethod(env, class_id, method_id, NULL);
117
118 res = (*_jvm)->DetachCurrentThread(_jvm);
119 if (res != JNI_OK) {
120 fprintf(stderr, "Test ERROR. Can't call detach from current thread\n");
121 exit(7);
122 }
123 }
124
125 void do_overflow(){
126 int *p = alloca(sizeof(int));
127 if (_kp_rec_count == 0 || _rec_count < _kp_rec_count) {
128 _rec_count ++;
129 do_overflow();
130 }
131 }
132
133 void *run_native_overflow(void *p) {
134 // Test that stack guard page is correctly set for initial and non initial thread
135 // and correctly removed for the initial thread
136 JNIEnv *env;
137 jclass class_id;
138 jmethodID method_id;
139 int res;
140
141 printf("run_native_overflow %ld\n", (long) gettid());
142
143 res = (*_jvm)->AttachCurrentThread(_jvm, (void **)&env, NULL);
144 if (res != JNI_OK) {
145 fprintf(stderr, "Test ERROR. Can't attach to current thread\n");
146 exit(7);
147 }
148
149 class_id = (*env)->FindClass (env, "DoOverflow");
150 if (class_id == NULL) {
151 fprintf(stderr, "Test ERROR. Can't load class DoOverflow\n");
152 exit(7);
153 }
154
155 method_id = (*env)->GetStaticMethodID (env, class_id, "printAlive", "()V");
156 if (method_id == NULL) {
157 fprintf(stderr, "Test ERROR. Can't find method DoOverflow.printAlive\n");
158 exit(7);
159 }
160
161 (*env)->CallStaticVoidMethod (env, class_id, method_id, NULL);
162
163 set_signal_handler();
164 if (! setjmp(context)) {
165 do_overflow();
166 }
167
168 if (_last_si_code == SEGV_ACCERR) {
169 printf("Test PASSED. Got access violation accessing guard page at %d\n", _rec_count);
170 }
171
172 res = (*_jvm)->DetachCurrentThread(_jvm);
173 if (res != JNI_OK) {
174 fprintf(stderr, "Test ERROR. Can't call detach from current thread\n");
175 exit(7);
176 }
177
178 if (getpid() != gettid()) {
179 // For non-initial thread we don't unmap the region but call os::uncommit_memory and keep PROT_NONE
180 // so if host has enough swap space we will get the same SEGV with code SEGV_ACCERR(2) trying
181 // to access it as if the guard page is present.
182 // We have no way to check this, so bail out, marking test as succeeded
183 printf("Test PASSED. Not initial thread\n");
184 return NULL;
185 }
186
187 // Limit depth of recursion for second run. It can't exceed one for first run.
188 _kp_rec_count = _rec_count;
189 _rec_count = 0;
190
191 set_signal_handler();
192 if (! setjmp(context)) {
193 do_overflow();
194 }
195
196 if (_last_si_code == SEGV_ACCERR) {
197 ++ _failures;
198 fprintf(stderr,"Test FAILED. Stack guard page is still there at %d\n", _rec_count);
199 } else if (_last_si_code == -1) {
200 printf("Test PASSED. No stack guard page is present. Maximum recursion level reached at %d\n", _rec_count);
201 }
202 else{
203 printf("Test PASSED. No stack guard page is present. SIGSEGV(%d) at %d\n", _last_si_code, _rec_count);
204 }
205
206 return NULL;
207 }
208
209 void usage() {
210 fprintf(stderr, "Usage: invoke test_java_overflow\n");
211 fprintf(stderr, " invoke test_native_overflow\n");
212 exit(7);
213 }
214
215
216 int main (int argc, const char** argv) {
217 JavaVMInitArgs vm_args;
218 JavaVMOption options[2];
219 JNIEnv* env;
220
221 printf("Test started with pid: %ld\n", (long) getpid());
222
223 options[0].optionString = "-Xint";
224 options[1].optionString = "-Xss328k";
225
226 vm_args.version = JNI_VERSION_1_2;
227 vm_args.ignoreUnrecognized = JNI_TRUE;
228 vm_args.options = options;
229 vm_args.nOptions = 2;
230
231 if (JNI_CreateJavaVM (&_jvm, (void **)&env, &vm_args) < 0 ) {
232 fprintf(stderr, "Test ERROR. Can't create JavaVM\n");
233 exit(7);
234 }
235
236 pthread_t thr;
237
238 if (argc > 1 && strcmp(argv[1], "test_java_overflow") == 0) {
239 printf("\nTesting JAVA_OVERFLOW\n");
240
241 printf("Testing stack guard page behaviour for other thread\n");
242 pthread_create (&thr, NULL, run_java_overflow, NULL);
243 pthread_join (thr, NULL);
244
245 printf("Testing stack guard page behaviour for initial thread\n");
246 run_java_overflow(NULL);
247 // This test crash on error
248 exit(0);
249 }
250
251 if (argc > 1 && strcmp(argv[1], "test_native_overflow") == 0) {
252 printf("\nTesting NATIVE_OVERFLOW\n");
253
254 printf("Testing stack guard page behaviour for other thread\n");
255 pthread_create (&thr, NULL, run_native_overflow, NULL);
256 pthread_join (thr, NULL);
257
258 printf("Testing stack guard page behaviour for initial thread\n");
259 run_native_overflow(NULL);
260
261 exit((_failures > 0) ? 1 : 0);
262 }
263
264 fprintf(stderr, "Test ERROR. Unknown parameter %s\n", ((argc > 1) ? argv[1] : "none"));
265 usage();
266 }