tests/exception_tests.c

   1 #include <darwintest.h>
   2 #include <pthread/private.h>
   3 #include <sys/sysctl.h>
   4 #include "exc_helpers.h"
   5
   6 T_GLOBAL_META(
   7         T_META_NAMESPACE("xnu.ipc"),
   8         T_META_RUN_CONCURRENTLY(true));
   9
  10 static size_t
  11 exc_immovable_handler(
  12         mach_port_t task,
  13         mach_port_t thread,
  14         __unused exception_type_t type,
  15         __unused mach_exception_data_t codes)
  16 {
  17         T_EXPECT_EQ(task, mach_task_self(), "Received immovable task port");
  18         T_EXPECT_EQ(thread, pthread_mach_thread_np(pthread_main_thread_np()),
  19             "Received immovable thread port");
  20         T_END;
  21 }
  22
  23 T_DECL(exc_immovable, "Test that exceptions receive immovable ports")
  24 {
  25         mach_port_t exc_port = create_exception_port(EXC_MASK_BAD_ACCESS);
  26         uint32_t opts = 0;
  27         size_t size = sizeof(&opts);
  28         mach_port_t mp;
  29         kern_return_t kr;
  30
  31         T_LOG("Check if task_exc_guard exception has been enabled\n");
  32         int ret = sysctlbyname("kern.ipc_control_port_options", &opts, &size, NULL, 0);
  33         T_EXPECT_POSIX_SUCCESS(ret, "sysctlbyname(kern.ipc_control_port_options)");
  34
  35         if ((opts & 0x30) == 0) {
  36                 T_SKIP("immovable rights aren't enabled");
  37         }
  38
  39         kr = task_get_special_port(mach_task_self(), TASK_KERNEL_PORT, &mp);
  40         T_EXPECT_MACH_SUCCESS(kr, "task_get_special_port");
  41         T_EXPECT_NE(mp, mach_task_self(), "should receive movable port");
  42
  43         /*
  44          * do not deallocate the port we received on purpose to check
  45          * that the exception will not coalesce with the movable port
  46          * we have in our space now
  47          */
  48
  49         run_exception_handler(exc_port, exc_immovable_handler);
  50         *(void *volatile*)0 = 0;
  51 }