tests/exc_resource_threads.c

   1 #ifdef T_NAMESPACE
   2 #undef T_NAMESPACE
   3 #endif
   4
   5
   6 #include <darwintest.h>
   7 #include <dispatch/dispatch.h>
   8 #include <stdlib.h>
   9 #include <spawn.h>
  10 #include <spawn_private.h>
  11
  12 #include <mach-o/dyld.h>
  13 #include <mach/mach.h>
  14 #include <mach/task.h>
  15
  16 #include <signal.h>
  17 #include <sys/sysctl.h>
  18 #include <sys/syslimits.h>
  19
  20 #include <excserver.h>
  21
  22 static dispatch_semaphore_t sync_sema;
  23
  24 kern_return_t
  25 catch_mach_exception_raise(mach_port_t exception_port,
  26     mach_port_t thread,
  27     mach_port_t task,
  28     exception_type_t exception,
  29     mach_exception_data_t code,
  30     mach_msg_type_number_t code_count)
  31 {
  32 #pragma unused(exception_port, thread, task, code, code_count)
  33         pid_t pid;
  34         pid_for_task(task, &pid);
  35         T_ASSERT_EQ(exception, EXC_CORPSE_NOTIFY, "exception type");
  36         T_ASSERT_POSIX_ZERO(kill(pid, SIGKILL), "kill");
  37         dispatch_semaphore_signal(sync_sema);
  38         return KERN_SUCCESS;
  39 }
  40
  41 kern_return_t
  42 catch_mach_exception_raise_state(mach_port_t exception_port,
  43     exception_type_t exception,
  44     const mach_exception_data_t code,
  45     mach_msg_type_number_t code_count,
  46     int * flavor,
  47     const thread_state_t old_state,
  48     mach_msg_type_number_t old_state_count,
  49     thread_state_t new_state,
  50     mach_msg_type_number_t * new_state_count)
  51 {
  52 #pragma unused(exception_port, exception, code, code_count, flavor, old_state, old_state_count, new_state, new_state_count)
  53         T_FAIL("Unsupported catch_mach_exception_raise_state");
  54         return KERN_NOT_SUPPORTED;
  55 }
  56
  57 kern_return_t
  58 catch_mach_exception_raise_state_identity(mach_port_t exception_port,
  59     mach_port_t thread,
  60     mach_port_t task,
  61     exception_type_t exception,
  62     mach_exception_data_t code,
  63     mach_msg_type_number_t code_count,
  64     int * flavor,
  65     thread_state_t old_state,
  66     mach_msg_type_number_t old_state_count,
  67     thread_state_t new_state,
  68     mach_msg_type_number_t * new_state_count)
  69 {
  70 #pragma unused(exception_port, thread, task, exception, code, code_count, flavor, old_state, old_state_count, new_state, new_state_count)
  71         T_FAIL("Unsupported catch_mach_exception_raise_state_identity");
  72         return KERN_NOT_SUPPORTED;
  73 }
  74
  75
  76 /*
  77  * setup exception handling port for EXC_CORPSE_NOTIFY.
  78  * runs mach_msg_server once for receiving exception messages from kernel.
  79  */
  80 static void *
  81 exc_handler(void * arg)
  82 {
  83 #pragma unused(arg)
  84         kern_return_t kret;
  85         mach_port_t exception_port;
  86
  87         kret = mach_port_allocate(mach_task_self(), MACH_PORT_RIGHT_RECEIVE, &exception_port);
  88         if (kret != KERN_SUCCESS) {
  89                 T_FAIL("mach_port_allocate: %s (%d)", mach_error_string(kret), kret);
  90         }
  91
  92         kret = mach_port_insert_right(mach_task_self(), exception_port, exception_port, MACH_MSG_TYPE_MAKE_SEND);
  93         if (kret != KERN_SUCCESS) {
  94                 T_FAIL("mach_port_insert_right: %s (%d)", mach_error_string(kret), kret);
  95         }
  96
  97         kret = task_set_exception_ports(mach_task_self(), EXC_MASK_CRASH | EXC_MASK_CORPSE_NOTIFY, exception_port,
  98             (exception_behavior_t)(EXCEPTION_DEFAULT | MACH_EXCEPTION_CODES), 0);
  99         if (kret != KERN_SUCCESS) {
 100                 T_FAIL("task_set_exception_ports: %s (%d)", mach_error_string(kret), kret);
 101         }
 102
 103         dispatch_semaphore_signal(sync_sema);
 104
 105         kret = mach_msg_server(mach_exc_server, MACH_MSG_SIZE_RELIABLE, exception_port, 0);
 106         if (kret != KERN_SUCCESS) {
 107                 T_FAIL("mach_msg_server: %s (%d)", mach_error_string(kret), kret);
 108         }
 109
 110         return NULL;
 111 }
 112
 113 static void*
 114 dummy_thread(void *arg)
 115 {
 116 #pragma unused(arg)
 117         while (1) {
 118                 sleep(60);
 119         }
 120 }
 121
 122 #define THREAD_LIMIT 2
 123
 124 T_HELPER_DECL(exc_resource_helper, "exc_resource helper")
 125 {
 126         pthread_t tid;
 127         for (int i = 0; i < THREAD_LIMIT; i++) {
 128                 T_QUIET;
 129                 T_EXPECT_POSIX_SUCCESS(pthread_create(&tid, NULL, dummy_thread, NULL), "pthread_create");
 130         }
 131         while (1) {
 132                 sleep(60);
 133         }
 134 }
 135
 136 static void
 137 check_exc_resource_threads_enabled()
 138 {
 139         int err;
 140         int enabled;
 141         size_t enabled_size = sizeof(enabled);
 142         err = sysctlbyname("kern.exc_resource_threads_enabled", &enabled, &enabled_size, NULL, 0);
 143
 144         if (err || !enabled) {
 145                 T_SKIP("EXC_RESOURCE RESOURCE_TYPE_THREADS not enabled on this system");
 146         }
 147 }
 148
 149 T_DECL(exc_resource_threads, "Ensures that a process with a thread_limit set will receive an exc_resource when it crosses its thread limit",
 150     T_META_ASROOT(true),
 151     T_META_CHECK_LEAKS(false))
 152 {
 153         pthread_t handle_thread;
 154
 155         check_exc_resource_threads_enabled();
 156
 157         sync_sema = dispatch_semaphore_create(0);
 158
 159         T_ASSERT_POSIX_ZERO(pthread_create(&handle_thread, NULL, exc_handler, NULL), "pthread_create");
 160         dispatch_semaphore_wait(sync_sema, DISPATCH_TIME_FOREVER);
 161
 162         pid_t helper_pid;
 163         char path[PATH_MAX];
 164         uint32_t path_size = sizeof(path);
 165
 166         T_ASSERT_POSIX_ZERO(_NSGetExecutablePath(path, &path_size), "_NSGetExecutablePath");
 167
 168         char *args[] = { path, "-n", "exc_resource_helper", NULL };
 169
 170         posix_spawnattr_t attr;
 171         T_ASSERT_POSIX_ZERO(posix_spawnattr_init(&attr), "posix_spawnattr_init");
 172
 173         T_EXPECT_POSIX_ZERO(posix_spawnattr_set_threadlimit_ext(&attr, THREAD_LIMIT), "posix_spawnattr_set_threadlimit_ext");
 174
 175         T_EXPECT_POSIX_ZERO(posix_spawn(&helper_pid, args[0], NULL, &attr, args, NULL), "posix_spawn");
 176
 177         T_ASSERT_POSIX_ZERO(posix_spawnattr_destroy(&attr), "posix_spawnattr_destroy");
 178
 179         dispatch_semaphore_wait(sync_sema, DISPATCH_TIME_FOREVER);
 180 }