1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <unistd.h>
4 #include <darwintest.h>
5 #include <mach/mach.h>
6 #include <mach/mach_vm.h>
7 #include <sys/sysctl.h>
8 #include <spawn.h>
9 #include <signal.h>
10 #include <TargetConditionals.h>
11 #include "excserver_protect.h"
12
13 #define MAX_ARGV 3
14 #define EXC_CODE_SHIFT 32
15 #define EXC_GUARD_TYPE_SHIFT 29
16 #define MAX_TEST_NUM 21
17
18 #define TASK_EXC_GUARD_MP_DELIVER 0x10
19
20 extern char **environ;
21 static uint64_t exception_code = 0;
22 static exception_type_t exception_taken = 0;
23
24 #define IKOT_TASK_CONTROL 2
25
26 #ifndef kGUARD_EXC_INVALID_OPTIONS
27 #define kGUARD_EXC_INVALID_OPTIONS 3
28 #endif
29
30 /*
31 * This test verifies behaviors of immovable/pinned task/thread ports.
32 *
33 * 1. Compare and verifies port names of mach_{task, thread}_self(),
34 * {TASK, THREAD}_KERNEL_PORT, and ports returned from task_threads()
35 * and processor_set_tasks().
36 * 2. Make sure correct exceptions are raised resulting from moving immovable
37 * task/thread control, read and inspect ports.
38 * 3. Make sure correct exceptions are raised resulting from deallocating pinned
39 * task/thread control ports.
40 * 4. Make sure immovable ports cannot be stashed:
41 * rdar://70585367 (Disallow immovable port stashing with *_set_special_port() and mach_port_register())
42 */
43 T_GLOBAL_META(
44 T_META_NAMESPACE("xnu.ipc"),
45 T_META_RADAR_COMPONENT_NAME("xnu"),
46 T_META_RADAR_COMPONENT_VERSION("IPC"),
47 T_META_RUN_CONCURRENTLY(TRUE));
48
49 static uint64_t soft_exception_code[] = {
50 EXC_GUARD, // Soft crash delivered as EXC_CORPSE_NOTIFY
51 EXC_GUARD,
52 EXC_GUARD,
53 EXC_GUARD,
54 EXC_GUARD,
55 EXC_GUARD,
56 EXC_GUARD,
57
58 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
59 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
60 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
61 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
62 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
63 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
64 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
65 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
66 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
67 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
68
69 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
70 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
71 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
72 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
73 };
74
75 static uint64_t hard_exception_code[] = {
76 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
77 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
78 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
79 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
80 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
81 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
82 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_MOD_REFS,
83
84 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
85 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
86 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
87 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
88 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
89 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
90 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
91 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
92 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
93 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_IMMOVABLE,
94
95 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
96 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
97 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
98 (GUARD_TYPE_MACH_PORT << EXC_GUARD_TYPE_SHIFT) | kGUARD_EXC_INVALID_OPTIONS,
99 };
100
101 kern_return_t
catch_mach_exception_raise_state(mach_port_t exception_port,exception_type_t exception,const mach_exception_data_t code,mach_msg_type_number_t code_count,int * flavor,const thread_state_t old_state,mach_msg_type_number_t old_state_count,thread_state_t new_state,mach_msg_type_number_t * new_state_count)102 catch_mach_exception_raise_state(mach_port_t exception_port,
103 exception_type_t exception,
104 const mach_exception_data_t code,
105 mach_msg_type_number_t code_count,
106 int * flavor,
107 const thread_state_t old_state,
108 mach_msg_type_number_t old_state_count,
109 thread_state_t new_state,
110 mach_msg_type_number_t * new_state_count)
111 {
112 #pragma unused(exception_port, exception, code, code_count, flavor, old_state, old_state_count, new_state, new_state_count)
113 T_FAIL("Unsupported catch_mach_exception_raise_state");
114 return KERN_NOT_SUPPORTED;
115 }
116
117 kern_return_t
catch_mach_exception_raise_identity_protected(mach_port_t exception_port,uint64_t thread_id,mach_port_t task_id_token,exception_type_t exception,mach_exception_data_t codes,mach_msg_type_number_t codeCnt)118 catch_mach_exception_raise_identity_protected(
119 mach_port_t exception_port,
120 uint64_t thread_id,
121 mach_port_t task_id_token,
122 exception_type_t exception,
123 mach_exception_data_t codes,
124 mach_msg_type_number_t codeCnt)
125 {
126 #pragma unused(exception_port, codeCnt)
127 task_t task;
128 pid_t pid;
129 kern_return_t kr = task_identity_token_get_task_port(task_id_token, TASK_FLAVOR_READ, &task);
130 T_ASSERT_MACH_SUCCESS(kr, "task_identity_token_get_task_port");
131 kr = pid_for_task(task, &pid);
132 T_ASSERT_MACH_SUCCESS(kr, "pid_for_task");
133 T_LOG("Crashing child pid: %d, continuing...\n", pid);
134
135 kr = mach_port_deallocate(mach_task_self(), task);
136 T_QUIET; T_EXPECT_MACH_SUCCESS(kr, "mach_port_deallocate");
137
138 T_ASSERT_GT_UINT(codeCnt, 0, "CodeCnt");
139 T_LOG("Caught exception type: %d code: 0x%llx", exception, (uint64_t)codes[0]);
140 if (exception == EXC_GUARD || exception == EXC_CORPSE_NOTIFY) {
141 exception_taken = exception;
142 exception_code = (uint64_t)codes[0];
143 } else {
144 T_FAIL("Unexpected exception");
145 }
146 return KERN_SUCCESS;
147 }
148
149 kern_return_t
catch_mach_exception_raise_state_identity(mach_port_t exception_port,mach_port_t thread,mach_port_t task,exception_type_t exception,mach_exception_data_t code,mach_msg_type_number_t code_count,int * flavor,thread_state_t old_state,mach_msg_type_number_t old_state_count,thread_state_t new_state,mach_msg_type_number_t * new_state_count)150 catch_mach_exception_raise_state_identity(mach_port_t exception_port,
151 mach_port_t thread,
152 mach_port_t task,
153 exception_type_t exception,
154 mach_exception_data_t code,
155 mach_msg_type_number_t code_count,
156 int * flavor,
157 thread_state_t old_state,
158 mach_msg_type_number_t old_state_count,
159 thread_state_t new_state,
160 mach_msg_type_number_t * new_state_count)
161 {
162 #pragma unused(exception_port, thread, task, exception, code, code_count, flavor, old_state, old_state_count, new_state, new_state_count)
163 T_FAIL("Unsupported catch_mach_exception_raise_state_identity");
164 return KERN_NOT_SUPPORTED;
165 }
166
167 kern_return_t
catch_mach_exception_raise(mach_port_t exception_port,mach_port_t thread,mach_port_t task,exception_type_t exception,mach_exception_data_t code,mach_msg_type_number_t code_count)168 catch_mach_exception_raise(mach_port_t exception_port,
169 mach_port_t thread,
170 mach_port_t task,
171 exception_type_t exception,
172 mach_exception_data_t code,
173 mach_msg_type_number_t code_count)
174 {
175 #pragma unused(exception_port, thread, task, exception, code, code_count, flavor, old_state, old_state_count, new_state, new_state_count)
176 T_FAIL("Unsupported catch_mach_exception_raise_state_identity");
177 return KERN_NOT_SUPPORTED;
178 }
179
180 static void *
exception_server_thread(void * arg)181 exception_server_thread(void *arg)
182 {
183 kern_return_t kr;
184 mach_port_t exc_port = *(mach_port_t *)arg;
185
186 /* Handle exceptions on exc_port */
187 kr = mach_msg_server_once(mach_exc_server, 4096, exc_port, 0);
188 T_QUIET; T_EXPECT_MACH_SUCCESS(kr, "mach_msg_server_once");
189
190 return NULL;
191 }
192
193 static mach_port_t
alloc_exception_port(void)194 alloc_exception_port(void)
195 {
196 kern_return_t kret;
197 mach_port_t exc_port = MACH_PORT_NULL;
198 mach_port_t task = mach_task_self();
199
200 kret = mach_port_allocate(task, MACH_PORT_RIGHT_RECEIVE, &exc_port);
201 T_QUIET; T_EXPECT_MACH_SUCCESS(kret, "mach_port_allocate exc_port");
202
203 kret = mach_port_insert_right(task, exc_port, exc_port, MACH_MSG_TYPE_MAKE_SEND);
204 T_QUIET; T_EXPECT_MACH_SUCCESS(kret, "mach_port_insert_right exc_port");
205
206 return exc_port;
207 }
208
209 static void
test_immovable_port_stashing(void)210 test_immovable_port_stashing(void)
211 {
212 kern_return_t kr;
213 mach_port_t port;
214
215 kr = task_set_special_port(mach_task_self(), TASK_BOOTSTRAP_PORT, mach_task_self());
216 T_EXPECT_EQ(kr, KERN_INVALID_RIGHT, "should disallow task_set_special_port() with immovable port");
217
218 kr = thread_set_special_port(mach_thread_self(), THREAD_KERNEL_PORT, mach_thread_self());
219 T_EXPECT_EQ(kr, KERN_INVALID_RIGHT, "should disallow task_set_special_port() with immovable port");
220
221 mach_port_t stash[1] = {mach_task_self()};
222 kr = mach_ports_register(mach_task_self(), stash, 1);
223 T_EXPECT_EQ(kr, KERN_INVALID_RIGHT, "should disallow mach_ports_register() with immovable port");
224
225 T_QUIET; T_ASSERT_MACH_SUCCESS(mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &port), "mach_port_allocate");
226 T_QUIET; T_ASSERT_MACH_SUCCESS(mach_port_insert_right(mach_task_self(), port, port, MACH_MSG_TYPE_MAKE_SEND), "mach_port_insert_right");
227
228 stash[0] = port;
229 kr = mach_ports_register(mach_task_self(), stash, 1);
230 T_EXPECT_MACH_SUCCESS(kr, "mach_ports_register() should succeed with movable port");
231 }
232
233 static void
test_task_thread_port_values(void)234 test_task_thread_port_values(void)
235 {
236 T_LOG("Compare various task/thread control port values\n");
237 kern_return_t kr;
238 mach_port_t port, th_self;
239 thread_array_t threadList;
240 mach_msg_type_number_t threadCount = 0;
241 boolean_t found_self = false;
242 processor_set_name_array_t psets;
243 processor_set_t pset_priv;
244 task_array_t taskList;
245 mach_msg_type_number_t pcnt = 0, tcnt = 0;
246 mach_port_t host = mach_host_self();
247
248 /* Compare with task/thread_get_special_port() */
249 kr = task_get_special_port(mach_task_self(), TASK_KERNEL_PORT, &port);
250 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "task_get_special_port() - TASK_KERNEL_PORT");
251 T_EXPECT_NE(port, mach_task_self(), "TASK_KERNEL_PORT should not match mach_task_self()");
252 mach_port_deallocate(mach_task_self(), port);
253
254 kr = task_for_pid(mach_task_self(), getpid(), &port);
255 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "task_for_pid()");
256 T_EXPECT_EQ(port, mach_task_self(), "task_for_pid(self) should match mach_task_self()");
257 mach_port_deallocate(mach_task_self(), port);
258
259 th_self = mach_thread_self();
260 kr = thread_get_special_port(th_self, THREAD_KERNEL_PORT, &port);
261 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "thread_get_special_port() - THREAD_KERNEL_PORT");
262 T_EXPECT_NE(port, th_self, "THREAD_KERNEL_PORT should not match mach_thread_self()");
263 mach_port_deallocate(mach_task_self(), port);
264
265 /* Make sure task_threads() return immovable thread ports */
266 kr = task_threads(mach_task_self(), &threadList, &threadCount);
267 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "task_threads()");
268 T_QUIET; T_ASSERT_GE(threadCount, 1, "should have at least 1 thread");
269
270 for (size_t i = 0; i < threadCount; i++) {
271 if (th_self == threadList[i]) { /* th_self is immovable */
272 found_self = true;
273 break;
274 }
275 }
276
277 T_EXPECT_TRUE(found_self, "task_threads() should return immovable thread self");
278
279 for (size_t i = 0; i < threadCount; i++) {
280 mach_port_deallocate(mach_task_self(), threadList[i]);
281 }
282
283 if (threadCount > 0) {
284 mach_vm_deallocate(mach_task_self(),
285 (mach_vm_address_t)threadList,
286 threadCount * sizeof(mach_port_t));
287 }
288
289 mach_port_deallocate(mach_task_self(), th_self);
290
291 /* Make sure processor_set_tasks() return immovable task self */
292 kr = host_processor_sets(host, &psets, &pcnt);
293 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "host_processor_sets");
294 T_QUIET; T_ASSERT_GE(pcnt, 1, "should have at least 1 processor set");
295
296 kr = host_processor_set_priv(host, psets[0], &pset_priv);
297 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "host_processor_set_priv");
298 for (size_t i = 0; i < pcnt; i++) {
299 mach_port_deallocate(mach_task_self(), psets[i]);
300 }
301 mach_port_deallocate(mach_task_self(), host);
302 vm_deallocate(mach_task_self(), (vm_address_t)psets, (vm_size_t)pcnt * sizeof(mach_port_t));
303
304 kr = processor_set_tasks_with_flavor(pset_priv, TASK_FLAVOR_CONTROL, &taskList, &tcnt);
305 T_QUIET; T_ASSERT_MACH_SUCCESS(kr, "processor_set_tasks_with_flavor");
306 T_QUIET; T_ASSERT_GE(tcnt, 1, "should have at least 1 task");
307 mach_port_deallocate(mach_task_self(), pset_priv);
308
309 found_self = false;
310 for (size_t i = 0; i < tcnt; i++) {
311 if (taskList[i] == mach_task_self()) {
312 found_self = true;
313 break;
314 }
315 }
316
317 T_EXPECT_TRUE(found_self, " processor_set_tasks() should return immovable task self");
318
319 for (size_t i = 0; i < tcnt; i++) {
320 mach_port_deallocate(mach_task_self(), taskList[i]);
321 }
322
323 if (tcnt > 0) {
324 mach_vm_deallocate(mach_task_self(),
325 (mach_vm_address_t)taskList,
326 tcnt * sizeof(mach_port_t));
327 }
328 }
329
330 T_DECL(imm_pinned_control_port, "Test pinned & immovable task and thread control ports",
331 T_META_IGNORECRASHES(".*pinned_rights_child.*"),
332 T_META_CHECK_LEAKS(false))
333 {
334 uint32_t task_exc_guard = 0;
335 size_t te_size = sizeof(&task_exc_guard);
336 posix_spawnattr_t attrs;
337 char *test_prog_name = "./imm_pinned_control_port_crasher";
338 char *child_args[MAX_ARGV];
339 pid_t client_pid = 0;
340 uint32_t opts = 0;
341 uint64_t *test_exception_code;
342 size_t size = sizeof(&opts);
343 mach_port_t exc_port;
344 pthread_t s_exc_thread;
345 uint64_t exc_id;
346
347 T_LOG("Check if task_exc_guard exception has been enabled\n");
348 int ret = sysctlbyname("kern.task_exc_guard_default", &task_exc_guard, &te_size, NULL, 0);
349 T_ASSERT_EQ(ret, 0, "sysctlbyname");
350
351 if (!(task_exc_guard & TASK_EXC_GUARD_MP_DELIVER)) {
352 T_SKIP("task_exc_guard exception is not enabled");
353 }
354
355 T_LOG("Check if immovable control port has been enabled\n");
356 ret = sysctlbyname("kern.ipc_control_port_options", &opts, &size, NULL, 0);
357
358 if (!ret && (opts & 0x8) != 0x8) {
359 T_SKIP("hard immovable control port isn't enabled");
360 }
361
362 if (!ret && (opts & 0x2)) {
363 T_LOG("Hard pinning enforcement is on.");
364 test_exception_code = hard_exception_code;
365 } else {
366 T_LOG("Hard pinning enforcement is off.");
367 test_exception_code = soft_exception_code;
368 }
369
370
371 /* first, try out comparing various task/thread ports */
372 test_task_thread_port_values();
373
374 /* try stashing immovable ports: rdar://70585367 */
375 test_immovable_port_stashing();
376
377 /* spawn a child and see if EXC_GUARD are correctly generated */
378 for (int i = 0; i < MAX_TEST_NUM; i++) {
379 /* Create the exception port for the child */
380 exc_port = alloc_exception_port();
381 T_QUIET; T_ASSERT_NE(exc_port, MACH_PORT_NULL, "Create a new exception port");
382
383 /* Create exception serving thread */
384 ret = pthread_create(&s_exc_thread, NULL, exception_server_thread, &exc_port);
385 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_create exception_server_thread");
386
387 /* Initialize posix_spawn attributes */
388 posix_spawnattr_init(&attrs);
389
390 int err = posix_spawnattr_setexceptionports_np(&attrs, EXC_MASK_GUARD | EXC_MASK_CORPSE_NOTIFY, exc_port,
391 (exception_behavior_t) (EXCEPTION_IDENTITY_PROTECTED | MACH_EXCEPTION_CODES), 0);
392 T_QUIET; T_ASSERT_POSIX_SUCCESS(err, "posix_spawnattr_setflags");
393
394 child_args[0] = test_prog_name;
395 char test_num[10];
396 sprintf(test_num, "%d", i);
397 child_args[1] = test_num;
398 child_args[2] = NULL;
399
400 T_LOG("========== Spawning new child ==========");
401 err = posix_spawn(&client_pid, child_args[0], NULL, &attrs, &child_args[0], environ);
402 T_ASSERT_POSIX_SUCCESS(err, "posix_spawn control_port_options_client = %d test_num = %d", client_pid, i);
403
404 /* try extracting child task port: rdar://71744817
405 * Moved to tests/extract_right_soft_fail.c
406 */
407 // test_extract_immovable_task_port(client_pid);
408
409 int child_status;
410 /* Wait for child and check for exception */
411 if (-1 == waitpid(-1, &child_status, 0)) {
412 T_FAIL("waitpid: child mia");
413 }
414
415 if (WIFEXITED(child_status) && WEXITSTATUS(child_status)) {
416 T_FAIL("Child exited with status = %x", child_status);
417 T_END;
418 }
419
420 sleep(1);
421 kill(1, SIGKILL);
422
423 ret = pthread_join(s_exc_thread, NULL);
424 T_QUIET; T_ASSERT_POSIX_SUCCESS(ret, "pthread_join");
425
426 if (exception_taken == EXC_GUARD) {
427 exc_id = exception_code >> EXC_CODE_SHIFT;
428 } else {
429 exc_id = exception_code;
430 }
431
432 T_LOG("Exception code: Received code = 0x%llx Expected code = 0x%llx", exc_id, test_exception_code[i]);
433 T_EXPECT_EQ(exc_id, test_exception_code[i], "Exception code: Received == Expected");
434 }
435 }
436