Exemplo n.º 1
0
/* Returns 1 if Data Execution Prevention is present and working */
static int AttemptToExecuteData()
{
  int result;
  char *thunk_buffer = g_malloc(64);
  nacl_void_thunk thunk;

  /* d'b: small fixes */
  if(thunk_buffer == NULL) return 0;
  thunk = GenerateThunk(thunk_buffer, 64);
  setup_signals();

  if(0 == sigsetjmp(try_state, 1))
  {
    thunk();
    result = 0;
  }
  else
  {
    result = 1;
  }

  restore_signals();
  g_free(thunk_buffer);
  return result;
}
Exemplo n.º 2
0
int main(int argc, char *argv[])
{
    int sockfd,r=0;

    if (argc != 3) {
        fprintf(stderr,"usage: %s server_hostname_or_ip port\n",argv[0]);
        return 1;
    }

    if(init_signals()==-1) {
        return 1;
    }

    sockfd=connect_to(argv[1],argv[2]);
    if(sockfd==INVALID_SOCKET) {
        return 1;
    }

    if(get_file(sockfd)==-1) {
        r=1;
    }

    if(close(sockfd)==-1) {
        perror("close");
        r=1;
    }

    if(restore_signals()==-1) {
        r=1;
    }

    return r;
}
Exemplo n.º 3
0
int initialize_signals()
{
    struct sigaction sa;

    for (size_t i = 0; i < sizeof(signals_used)/sizeof(signals_used[0]); i++)
    {
        if (!sd_is_handler_registered(signals_used[i].port_sig) &&
                signals_used[i].signal != SIGSEGV) // Sigsegv is needed for port_memaccess
            continue;

        sigemptyset(&sa.sa_mask);
        sa.sa_flags = signals_used[i].flags;
        sa.sa_sigaction = &general_signal_handler;

        if (0 != sigaction(signals_used[i].signal, &sa, &old_actions[i]))
        {
            restore_signals();
            return -1;
        }

        signals_used[i].set_up = true;
    }

    for (size_t j = 0; j < sizeof(signals_other)/sizeof(signals_other[0]); j++)
    {
        old_handlers[j] = signal(signals_other[j].signal, signals_other[j].handler);
        if (old_handlers[j] == SIG_ERR)
        {
            restore_signals();
            return -1;
        }
        signals_other[j].set_up = true;
    }

    // Prepare gdb crash handler
    if (!init_gdb_crash_handler())
    {
        restore_signals();
        return -1;
    }

    return 0;

} //initialize_signals
Exemplo n.º 4
0
int
thr_sigsetmask(int how, const sigset_t *set, sigset_t *oset)
{
	ulwp_t *self = curthread;
	sigset_t saveset;

	if (set == NULL) {
		enter_critical(self);
		if (oset != NULL)
			*oset = self->ul_sigmask;
		exit_critical(self);
	} else {
		switch (how) {
		case SIG_BLOCK:
		case SIG_UNBLOCK:
		case SIG_SETMASK:
			break;
		default:
			return (EINVAL);
		}

		/*
		 * The assignments to self->ul_sigmask must be protected from
		 * signals.  The nuances of this code are subtle.  Be careful.
		 */
		block_all_signals(self);
		if (oset != NULL)
			saveset = self->ul_sigmask;
		switch (how) {
		case SIG_BLOCK:
			self->ul_sigmask.__sigbits[0] |= set->__sigbits[0];
			self->ul_sigmask.__sigbits[1] |= set->__sigbits[1];
			self->ul_sigmask.__sigbits[2] |= set->__sigbits[2];
			self->ul_sigmask.__sigbits[3] |= set->__sigbits[3];
			break;
		case SIG_UNBLOCK:
			self->ul_sigmask.__sigbits[0] &= ~set->__sigbits[0];
			self->ul_sigmask.__sigbits[1] &= ~set->__sigbits[1];
			self->ul_sigmask.__sigbits[2] &= ~set->__sigbits[2];
			self->ul_sigmask.__sigbits[3] &= ~set->__sigbits[3];
			break;
		case SIG_SETMASK:
			self->ul_sigmask.__sigbits[0] = set->__sigbits[0];
			self->ul_sigmask.__sigbits[1] = set->__sigbits[1];
			self->ul_sigmask.__sigbits[2] = set->__sigbits[2];
			self->ul_sigmask.__sigbits[3] = set->__sigbits[3];
			break;
		}
		delete_reserved_signals(&self->ul_sigmask);
		if (oset != NULL)
			*oset = saveset;
		restore_signals(self);
	}

	return (0);
}
Exemplo n.º 5
0
/*
 * Threads restoration via sigreturn. Note it's locked
 * routine and calls for unlock at the end.
 */
long __export_restore_thread(struct thread_restore_args *args)
{
	struct rt_sigframe *rt_sigframe;
	k_rtsigset_t to_block;
	unsigned long new_sp;
	int my_pid = sys_gettid();
	int ret;

	if (my_pid != args->pid) {
		pr_err("Thread pid mismatch %d/%d\n", my_pid, args->pid);
		goto core_restore_end;
	}

	/* All signals must be handled by thread leader */
	ksigfillset(&to_block);
	ret = sys_sigprocmask(SIG_SETMASK, &to_block, NULL, sizeof(k_rtsigset_t));
	if (ret) {
		pr_err("Unable to block signals %d", ret);
		goto core_restore_end;
	}

	rt_sigframe = (void *)args->mem_zone.rt_sigframe;

	if (restore_thread_common(rt_sigframe, args))
		goto core_restore_end;

	ret = restore_creds(&args->ta->creds);
	if (ret)
		goto core_restore_end;

	ret = restore_dumpable_flag(&args->ta->mm);
	if (ret)
		goto core_restore_end;

	pr_info("%ld: Restored\n", sys_gettid());

	restore_finish_stage(CR_STATE_RESTORE);

	if (restore_signals(args->siginfo, args->siginfo_nr, false))
		goto core_restore_end;

	restore_finish_stage(CR_STATE_RESTORE_SIGCHLD);
	restore_pdeath_sig(args);
	restore_finish_stage(CR_STATE_RESTORE_CREDS);
	futex_dec_and_wake(&thread_inprogress);

	new_sp = (long)rt_sigframe + SIGFRAME_OFFSET;
	rst_sigreturn(new_sp);

core_restore_end:
	pr_err("Restorer abnormal termination for %ld\n", sys_getpid());
	futex_abort_and_wake(&task_entries->nr_in_progress);
	sys_exit_group(1);
	return -1;
}
Exemplo n.º 6
0
VALUE furnsh(int argc, VALUE *argv, VALUE self) {
  sigset_t old_mask = block_signals();

  furnsh_c(StringValuePtr(argv[0]));

  restore_signals(old_mask);
  
  if(spice_error(SHORT)) return Qfalse;

  return Qtrue;
}
Exemplo n.º 7
0
static VALUE unload(VALUE self, VALUE kernel) {
  sigset_t old_mask = block_signals();

  unload_c(StringValuePtr(kernel));
  
  restore_signals(old_mask);
  
  if(spice_error(SPICE_ERROR_SHORT)) return Qfalse;

  return Qtrue;
}
Exemplo n.º 8
0
/** Initializes all ncurses' related stuff (windows, colors...).
 *  There's no need to call 'engine_exit' */
bool engine_init()
{
    /* signals during initialization */
    block_signals();

    engine_screen_init(80, 24);
    engine_windows_init();
    engine_keymap(NULL);

    restore_signals();
    register_signal_handler();
    return true;
}
Exemplo n.º 9
0
void
xmutex_unlock(struct xmutex * lock, sigset_t sigset)
{
	TRACE(MUTEX, "thread %d:%d is unlocking %p\n",
			sys_getpid(), sys_gettid(), lock);
	/* atomic_dec(&lock->val) != 1 */
	if (!atomic_dec_and_test(&lock->val)) {
		atomic_set(&lock->val, 0);
		futex_wake(&lock->val, 1);
	}
	restore_signals(sigset);
	TRACE(MUTEX, "thread %d:%d unlocked %p\n",
			sys_getpid(), sys_gettid(), lock);
}
Exemplo n.º 10
0
/*
 * Returns 1 if Data Execution Prevention is present and working.
 */
int NaClAttemptToExecuteData() {
  int result;
  char *thunk_buffer = malloc(64);
  nacl_void_thunk thunk = NaClGenerateThunk(thunk_buffer, 64);

  setup_signals();

  if (0 == sigsetjmp(try_state, 1)) {
    thunk();
    result = 0;
  } else {
    result = 1;
  }

  restore_signals();
  return result;
}
Exemplo n.º 11
0
/*
 * Threads restoration via sigreturn. Note it's locked
 * routine and calls for unlock at the end.
 */
long __export_restore_thread(struct thread_restore_args *args)
{
	struct rt_sigframe *rt_sigframe;
	unsigned long new_sp;
	int my_pid = sys_gettid();
	int ret;

	if (my_pid != args->pid) {
		pr_err("Thread pid mismatch %d/%d\n", my_pid, args->pid);
		goto core_restore_end;
	}

	rt_sigframe = (void *)args->mem_zone.rt_sigframe + 8;

	if (restore_thread_common(rt_sigframe, args))
		goto core_restore_end;

	mutex_unlock(&args->ta->rst_lock);

	ret = restore_creds(&args->ta->creds);
	if (ret)
		goto core_restore_end;

	pr_info("%ld: Restored\n", sys_gettid());

	restore_finish_stage(CR_STATE_RESTORE);

	if (restore_signals(args->siginfo, args->siginfo_nr, false))
		goto core_restore_end;

	restore_finish_stage(CR_STATE_RESTORE_SIGCHLD);
	restore_finish_stage(CR_STATE_RESTORE_CREDS);
	futex_dec_and_wake(&thread_inprogress);

	new_sp = (long)rt_sigframe + SIGFRAME_OFFSET;
	ARCH_RT_SIGRETURN(new_sp);

core_restore_end:
	pr_err("Restorer abnormal termination for %ld\n", sys_getpid());
	futex_abort_and_wake(&task_entries->nr_in_progress);
	sys_exit_group(1);
	return -1;
}
Exemplo n.º 12
0
int NaClAttemptToExecuteDataAtAddr(char *thunk_buffer, size_t size) {
  int result;
  MachExceptionHandlerData saved_handlers;
  nacl_void_thunk thunk = NaClGenerateThunk(thunk_buffer, size);

  setup_signals();
  DisableMachExceptionHandler(&saved_handlers);

  if (0 == sigsetjmp(try_state, 1)) {
    thunk();
    result = 0;
  } else {
    result = 1;
  }

  EnableMachExceptionHandler(&saved_handlers);
  restore_signals();

  return result;
}
Exemplo n.º 13
0
int main(int argc, char* argv[])
{
    // parse options
    addpd::options options(argc, argv);

    // create server
    server s(options.port(), options.multicast());

    // run server in background thread
    sigset_t sigmask = block_signals();
    boost::thread t(boost::bind(&server::run, &s));
    restore_signals(sigmask);

    // wait for signal to terminate
    wait_for_signal();

    // stop the server
    s.stop();
    t.join();

    return 0;
}
Exemplo n.º 14
0
void shell_out(void){
  char *comspec;
#ifndef __TURBOC__
  char key;
  int val;
  char *str;
#endif /* __TURBOC__ */
  save_screen();
  clear_screen();
  puts("[Entering DOS shell, type exit to return to game.]");
  msdos_noraw();
  ignore_signals();
  if((comspec=getenv("COMSPEC")) ==NULL ||
    spawnl(P_WAIT,comspec,comspec,(char *)NULL)<0){
    puts("Sorry, there seems to be a problem with shell_out()");
    printf("comspec = %s\n",comspec);
    flush();
    puts("Hit a key to continue");
    while(!kbhit())
      ;
  }
  restore_signals();
  restore_screen();
}
Exemplo n.º 15
0
void julia_init(char *imageFile)
{
    (void)uv_default_loop();
    restore_signals(); //XXX: this needs to be early in load process
    jl_page_size = sysconf(_SC_PAGESIZE);
    jl_find_stack_bottom();
    jl_dl_handle = jl_load_dynamic_library(NULL);

#if defined(__linux__)
    int ncores = jl_cpu_cores();
    if (ncores > 1) {
        cpu_set_t cpumask;
        CPU_ZERO(&cpumask);
        for(int i=0; i < ncores; i++) {
            CPU_SET(i, &cpumask);
        }
        sched_setaffinity(0, sizeof(cpu_set_t), &cpumask);
    }
#endif

#ifdef JL_GC_MARKSWEEP
    jl_gc_init();
    jl_gc_disable();
#endif
    jl_init_frontend();
    jl_init_types();
    jl_init_tasks(jl_stack_lo, jl_stack_hi-jl_stack_lo);
    jl_init_codegen();
    jl_an_empty_cell = (jl_value_t*)jl_alloc_cell_1d(0);

    jl_init_serializer();

    if (!imageFile) {
        jl_main_module = jl_new_module(jl_symbol("Main"));
        jl_main_module->parent = jl_main_module;
        jl_core_module = jl_new_module(jl_symbol("Core"));
        jl_core_module->parent = jl_main_module;
        jl_set_const(jl_main_module, jl_symbol("Core"),
                     (jl_value_t*)jl_core_module);
        jl_module_using(jl_main_module, jl_core_module);
        jl_current_module = jl_core_module;
        jl_init_intrinsic_functions();
        jl_init_primitives();
        jl_load("boot.jl");
        jl_get_builtin_hooks();
        jl_boot_file_loaded = 1;
        jl_init_box_caches();
    }

    if (imageFile) {
        JL_TRY {
            jl_restore_system_image(imageFile);
        }
        JL_CATCH {
            JL_PRINTF(JL_STDERR, "error during init:\n");
            jl_show(jl_stderr_obj(), jl_exception_in_transit);
            JL_PRINTF(JL_STDOUT, "\n");
            jl_exit(1);
        }
    }

    // set module field of primitive types
    int i;
    void **table = jl_core_module->bindings.table;
    for(i=1; i < jl_core_module->bindings.size; i+=2) {
        if (table[i] != HT_NOTFOUND) {
            jl_binding_t *b = (jl_binding_t*)table[i];
            if (b->value && jl_is_some_tag_type(b->value)) {
                jl_tag_type_t *tt = (jl_tag_type_t*)b->value;
                tt->name->module = jl_core_module;
            }
        }
    }

    // the Main module is the one which is always open, and set as the
    // current module for bare (non-module-wrapped) toplevel expressions.
    // it does "using Base" if Base is available.
    if (jl_base_module != NULL)
        jl_module_using(jl_main_module, jl_base_module);
    jl_current_module = jl_main_module;

#ifndef __WIN32__
    struct sigaction actf;
    memset(&actf, 0, sizeof(struct sigaction));
    sigemptyset(&actf.sa_mask);
    actf.sa_handler = fpe_handler;
    actf.sa_flags = 0;
    if (sigaction(SIGFPE, &actf, NULL) < 0) {
        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
        jl_exit(1);
    }

    stack_t ss;
    ss.ss_flags = 0;
    ss.ss_size = SIGSTKSZ;
    ss.ss_sp = malloc(ss.ss_size);
    if (sigaltstack(&ss, NULL) < 0) {
        JL_PRINTF(JL_STDERR, "sigaltstack: %s\n", strerror(errno));
        jl_exit(1);
    }

    struct sigaction act;
    memset(&act, 0, sizeof(struct sigaction));
    sigemptyset(&act.sa_mask);
    act.sa_sigaction = segv_handler;
    act.sa_flags = SA_ONSTACK | SA_SIGINFO;
    if (sigaction(SIGSEGV, &act, NULL) < 0) {
        JL_PRINTF(JL_STDERR, "sigaction: %s\n", strerror(errno));
        jl_exit(1);
    }
#endif

    atexit(jl_atexit_hook);

#ifdef JL_GC_MARKSWEEP
    jl_gc_enable();
#endif
}
Exemplo n.º 16
0
/*
 * The main routine to restore task via sigreturn.
 * This one is very special, we never return there
 * but use sigreturn facility to restore core registers
 * and jump execution to some predefined ip read from
 * core file.
 */
long __export_restore_task(struct task_restore_core_args *args)
{
	long ret = -1;
	VmaEntry *vma_entry;
	u64 va;
	unsigned long premmapped_end = args->premmapped_addr + args->premmapped_len;

	struct rt_sigframe *rt_sigframe;
	unsigned long new_sp;
	pid_t my_pid = sys_getpid();
	rt_sigaction_t act;

	task_entries = args->task_entries;

	ksigfillset(&act.rt_sa_mask);
	act.rt_sa_handler = sigchld_handler;
	act.rt_sa_flags = SA_SIGINFO | SA_RESTORER | SA_RESTART;
	act.rt_sa_restorer = cr_restore_rt;
	sys_sigaction(SIGCHLD, &act, NULL, sizeof(k_rtsigset_t));

	log_set_fd(args->logfd);
	log_set_loglevel(args->loglevel);

	cap_last_cap = args->cap_last_cap;

	pr_info("Switched to the restorer %d\n", my_pid);

	for (vma_entry = args->self_vmas; vma_entry->start != 0; vma_entry++) {
		unsigned long addr = vma_entry->start;
		unsigned long len;

		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		pr_debug("Examine %"PRIx64"-%"PRIx64"\n", vma_entry->start, vma_entry->end);

		if (addr < args->premmapped_addr) {
			if (vma_entry->end >= args->premmapped_addr)
				len = args->premmapped_addr - addr;
			else
				len = vma_entry->end - vma_entry->start;
			if (sys_munmap((void *) addr, len)) {
				pr_err("munmap fail for %lx - %lx\n", addr, addr + len);
				goto core_restore_end;
			}
		}

		if (vma_entry->end >= TASK_SIZE)
			continue;

		if (vma_entry->end > premmapped_end) {
			if (vma_entry->start < premmapped_end)
				addr = premmapped_end;
			len = vma_entry->end - addr;
			if (sys_munmap((void *) addr, len)) {
				pr_err("munmap fail for %lx - %lx\n", addr, addr + len);
				goto core_restore_end;
			}
		}
	}

	sys_munmap(args->self_vmas,
			((void *)(vma_entry + 1) - ((void *)args->self_vmas)));

	/* Shift private vma-s to the left */
	for (vma_entry = args->tgt_vmas; vma_entry->start != 0; vma_entry++) {
		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (!vma_priv(vma_entry))
			continue;

		if (vma_entry->end >= TASK_SIZE)
			continue;

		if (vma_entry->start > vma_entry->shmid)
			break;

		if (vma_remap(vma_premmaped_start(vma_entry),
				vma_entry->start, vma_entry_len(vma_entry)))
			goto core_restore_end;
	}

	/* Shift private vma-s to the right */
	for (vma_entry = args->tgt_vmas + args->nr_vmas -1;
				vma_entry >= args->tgt_vmas; vma_entry--) {
		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (!vma_priv(vma_entry))
			continue;

		if (vma_entry->start > TASK_SIZE)
			continue;

		if (vma_entry->start < vma_entry->shmid)
			break;

		if (vma_remap(vma_premmaped_start(vma_entry),
				vma_entry->start, vma_entry_len(vma_entry)))
			goto core_restore_end;
	}

	/*
	 * OK, lets try to map new one.
	 */
	for (vma_entry = args->tgt_vmas; vma_entry->start != 0; vma_entry++) {
		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (vma_priv(vma_entry))
			continue;

		va = restore_mapping(vma_entry);

		if (va != vma_entry->start) {
			pr_err("Can't restore %"PRIx64" mapping with %"PRIx64"\n", vma_entry->start, va);
			goto core_restore_end;
		}
	}

	/*
	 * Walk though all VMAs again to drop PROT_WRITE
	 * if it was not there.
	 */
	for (vma_entry = args->tgt_vmas; vma_entry->start != 0; vma_entry++) {
		if (!(vma_entry_is(vma_entry, VMA_AREA_REGULAR)))
			continue;

		if (vma_entry_is(vma_entry, VMA_ANON_SHARED)) {
			struct shmem_info *entry;

			entry = find_shmem(args->shmems,
						  vma_entry->shmid);
			if (entry && entry->pid == my_pid &&
			    entry->start == vma_entry->start)
				futex_set_and_wake(&entry->lock, 1);
		}

		if (vma_entry->prot & PROT_WRITE)
			continue;

		sys_mprotect(decode_pointer(vma_entry->start),
			     vma_entry_len(vma_entry),
			     vma_entry->prot);
	}

	/*
	 * Finally restore madivse() bits
	 */
	for (vma_entry = args->tgt_vmas; vma_entry->start != 0; vma_entry++) {
		unsigned long i;

		if (!vma_entry->has_madv || !vma_entry->madv)
			continue;
		for (i = 0; i < sizeof(vma_entry->madv) * 8; i++) {
			if (vma_entry->madv & (1ul << i)) {
				ret = sys_madvise(vma_entry->start,
						  vma_entry_len(vma_entry),
						  i);
				if (ret) {
					pr_err("madvise(%"PRIx64", %"PRIu64", %ld) "
					       "failed with %ld\n",
						vma_entry->start,
						vma_entry_len(vma_entry),
						i, ret);
					goto core_restore_end;
				}
			}
		}
	}

	sys_munmap(args->tgt_vmas,
			((void *)(vma_entry + 1) - ((void *)args->tgt_vmas)));

	ret = sys_munmap(args->shmems, SHMEMS_SIZE);
	if (ret < 0) {
		pr_err("Can't unmap shmem %ld\n", ret);
		goto core_restore_end;
	}

	/*
	 * Tune up the task fields.
	 */
	ret |= sys_prctl_safe(PR_SET_NAME, (long)args->comm, 0, 0);

	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_CODE,	(long)args->mm.mm_start_code, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_CODE,	(long)args->mm.mm_end_code, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_DATA,	(long)args->mm.mm_start_data, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_DATA,	(long)args->mm.mm_end_data, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_STACK,	(long)args->mm.mm_start_stack, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_BRK,	(long)args->mm.mm_start_brk, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_BRK,		(long)args->mm.mm_brk, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_START,	(long)args->mm.mm_arg_start, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_END,	(long)args->mm.mm_arg_end, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_START,	(long)args->mm.mm_env_start, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_END,	(long)args->mm.mm_env_end, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_AUXV,	(long)args->mm_saved_auxv, args->mm_saved_auxv_size);
	if (ret)
		goto core_restore_end;

	/*
	 * Because of requirements applied from kernel side
	 * we need to restore /proc/pid/exe symlink late,
	 * after old existing VMAs are superseded with
	 * new ones from image file.
	 */
	ret = restore_self_exe_late(args);
	if (ret)
		goto core_restore_end;

	/*
	 * We need to prepare a valid sigframe here, so
	 * after sigreturn the kernel will pick up the
	 * registers from the frame, set them up and
	 * finally pass execution to the new IP.
	 */
	rt_sigframe = (void *)args->t->mem_zone.rt_sigframe + 8;

	if (restore_thread_common(rt_sigframe, args->t))
		goto core_restore_end;

	/*
	 * Threads restoration. This requires some more comments. This
	 * restorer routine and thread restorer routine has the following
	 * memory map, prepared by a caller code.
	 *
	 * | <-- low addresses                                          high addresses --> |
	 * +-------------------------------------------------------+-----------------------+
	 * | this proc body | own stack | heap | rt_sigframe space | thread restore zone   |
	 * +-------------------------------------------------------+-----------------------+
	 *
	 * where each thread restore zone is the following
	 *
	 * | <-- low addresses                                     high addresses --> |
	 * +--------------------------------------------------------------------------+
	 * | thread restore proc | thread1 stack | thread1 heap | thread1 rt_sigframe |
	 * +--------------------------------------------------------------------------+
	 */

	if (args->nr_threads > 1) {
		struct thread_restore_args *thread_args = args->thread_args;
		long clone_flags = CLONE_VM | CLONE_FILES | CLONE_SIGHAND	|
				   CLONE_THREAD | CLONE_SYSVSEM;
		long last_pid_len;
		long parent_tid;
		int i, fd;

		fd = sys_open(LAST_PID_PATH, O_RDWR, LAST_PID_PERM);
		if (fd < 0) {
			pr_err("Can't open last_pid %d\n", fd);
			goto core_restore_end;
		}

		ret = sys_flock(fd, LOCK_EX);
		if (ret) {
			pr_err("Can't lock last_pid %d\n", fd);
			goto core_restore_end;
		}

		for (i = 0; i < args->nr_threads; i++) {
			char last_pid_buf[16], *s;

			/* skip self */
			if (thread_args[i].pid == args->t->pid)
				continue;

			mutex_lock(&args->rst_lock);

			new_sp =
				RESTORE_ALIGN_STACK((long)thread_args[i].mem_zone.stack,
						    sizeof(thread_args[i].mem_zone.stack));

			last_pid_len = vprint_num(last_pid_buf, sizeof(last_pid_buf), thread_args[i].pid - 1, &s);
			ret = sys_write(fd, s, last_pid_len);
			if (ret < 0) {
				pr_err("Can't set last_pid %ld/%s\n", ret, last_pid_buf);
				goto core_restore_end;
			}

			/*
			 * To achieve functionality like libc's clone()
			 * we need a pure assembly here, because clone()'ed
			 * thread will run with own stack and we must not
			 * have any additional instructions... oh, dear...
			 */

			RUN_CLONE_RESTORE_FN(ret, clone_flags, new_sp, parent_tid, thread_args, args->clone_restore_fn);
		}

		ret = sys_flock(fd, LOCK_UN);
		if (ret) {
			pr_err("Can't unlock last_pid %ld\n", ret);
			goto core_restore_end;
		}

		sys_close(fd);
	}

	restore_rlims(args);

	pr_info("%ld: Restored\n", sys_getpid());

	futex_set(&zombies_inprogress, args->nr_zombies);

	restore_finish_stage(CR_STATE_RESTORE);

	futex_wait_while_gt(&zombies_inprogress, 0);

	sys_sigaction(SIGCHLD, &args->sigchld_act, NULL, sizeof(k_rtsigset_t));

	ret = restore_signals(args->siginfo, args->siginfo_nr, true);
	if (ret)
		goto core_restore_end;

	ret = restore_signals(args->t->siginfo, args->t->siginfo_nr, false);
	if (ret)
		goto core_restore_end;

	restore_finish_stage(CR_STATE_RESTORE_SIGCHLD);

	if (args->siginfo_size) {
		ret = sys_munmap(args->siginfo, args->siginfo_size);
		if (ret < 0) {
			pr_err("Can't unmap signals %ld\n", ret);
			goto core_restore_failed;
		}
	}

	rst_tcp_socks_all(args->rst_tcp_socks, args->rst_tcp_socks_size);

	/* 
	 * Writing to last-pid is CAP_SYS_ADMIN protected,
	 * turning off TCP repair is CAP_SYS_NED_ADMIN protected,
	 * thus restore* creds _after_ all of the above.
	 */

	ret = restore_creds(&args->creds);

	futex_set_and_wake(&thread_inprogress, args->nr_threads);

	restore_finish_stage(CR_STATE_RESTORE_CREDS);

	if (ret)
		BUG();

	/* Wait until children stop to use args->task_entries */
	futex_wait_while_gt(&thread_inprogress, 1);

	log_set_fd(-1);

	/*
	 * The code that prepared the itimers makes shure the
	 * code below doesn't fail due to bad timing values.
	 */

#define itimer_armed(args, i)				\
		(args->itimers[i].it_interval.tv_sec ||	\
		 args->itimers[i].it_interval.tv_usec)

	if (itimer_armed(args, 0))
		sys_setitimer(ITIMER_REAL, &args->itimers[0], NULL);
	if (itimer_armed(args, 1))
		sys_setitimer(ITIMER_VIRTUAL, &args->itimers[1], NULL);
	if (itimer_armed(args, 2))
		sys_setitimer(ITIMER_PROF, &args->itimers[2], NULL);

	ret = sys_munmap(args->task_entries, TASK_ENTRIES_SIZE);
	if (ret < 0) {
		ret = ((long)__LINE__ << 16) | ((-ret) & 0xffff);
		goto core_restore_failed;
	}

	/*
	 * Sigframe stack.
	 */
	new_sp = (long)rt_sigframe + SIGFRAME_OFFSET;

	/*
	 * Prepare the stack and call for sigreturn,
	 * pure assembly since we don't need any additional
	 * code insns from gcc.
	 */
	ARCH_RT_SIGRETURN(new_sp);

core_restore_end:
	futex_abort_and_wake(&task_entries->nr_in_progress);
	pr_err("Restorer fail %ld\n", sys_getpid());
	sys_exit_group(1);
	return -1;

core_restore_failed:
	ARCH_FAIL_CORE_RESTORE;

	return ret;
}
Exemplo n.º 17
0
/*
 * The main routine to restore task via sigreturn.
 * This one is very special, we never return there
 * but use sigreturn facility to restore core registers
 * and jump execution to some predefined ip read from
 * core file.
 */
long __export_restore_task(struct task_restore_args *args)
{
	long ret = -1;
	int i;
	VmaEntry *vma_entry;
	unsigned long va;

	struct rt_sigframe *rt_sigframe;
	unsigned long new_sp;
	k_rtsigset_t to_block;
	pid_t my_pid = sys_getpid();
	rt_sigaction_t act;

	bootstrap_start = args->bootstrap_start;
	bootstrap_len	= args->bootstrap_len;

#ifdef CONFIG_VDSO
	vdso_rt_size	= args->vdso_rt_size;
#endif

	task_entries = args->task_entries;
	helpers = args->helpers;
	n_helpers = args->n_helpers;
	*args->breakpoint = rst_sigreturn;

	ksigfillset(&act.rt_sa_mask);
	act.rt_sa_handler = sigchld_handler;
	act.rt_sa_flags = SA_SIGINFO | SA_RESTORER | SA_RESTART;
	act.rt_sa_restorer = cr_restore_rt;
	sys_sigaction(SIGCHLD, &act, NULL, sizeof(k_rtsigset_t));

	log_set_fd(args->logfd);
	log_set_loglevel(args->loglevel);

	cap_last_cap = args->cap_last_cap;

	pr_info("Switched to the restorer %d\n", my_pid);

#ifdef CONFIG_VDSO
	if (vdso_do_park(&args->vdso_sym_rt, args->vdso_rt_parked_at, vdso_rt_size))
		goto core_restore_end;
#endif

	if (unmap_old_vmas((void *)args->premmapped_addr, args->premmapped_len,
				bootstrap_start, bootstrap_len))
		goto core_restore_end;

	/* Shift private vma-s to the left */
	for (i = 0; i < args->nr_vmas; i++) {
		vma_entry = args->tgt_vmas + i;

		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (!vma_priv(vma_entry))
			continue;

		if (vma_entry->end >= TASK_SIZE)
			continue;

		if (vma_entry->start > vma_entry->shmid)
			break;

		if (vma_remap(vma_premmaped_start(vma_entry),
				vma_entry->start, vma_entry_len(vma_entry)))
			goto core_restore_end;
	}

	/* Shift private vma-s to the right */
	for (i = args->nr_vmas - 1; i >= 0; i--) {
		vma_entry = args->tgt_vmas + i;

		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (!vma_priv(vma_entry))
			continue;

		if (vma_entry->start > TASK_SIZE)
			continue;

		if (vma_entry->start < vma_entry->shmid)
			break;

		if (vma_remap(vma_premmaped_start(vma_entry),
				vma_entry->start, vma_entry_len(vma_entry)))
			goto core_restore_end;
	}

	/*
	 * OK, lets try to map new one.
	 */
	for (i = 0; i < args->nr_vmas; i++) {
		vma_entry = args->tgt_vmas + i;

		if (!vma_entry_is(vma_entry, VMA_AREA_REGULAR))
			continue;

		if (vma_priv(vma_entry))
			continue;

		va = restore_mapping(vma_entry);

		if (va != vma_entry->start) {
			pr_err("Can't restore %"PRIx64" mapping with %lx\n", vma_entry->start, va);
			goto core_restore_end;
		}
	}

#ifdef CONFIG_VDSO
	/*
	 * Proxify vDSO.
	 */
	for (i = 0; i < args->nr_vmas; i++) {
		if (vma_entry_is(&args->tgt_vmas[i], VMA_AREA_VDSO) ||
		    vma_entry_is(&args->tgt_vmas[i], VMA_AREA_VVAR)) {
			if (vdso_proxify("dumpee", &args->vdso_sym_rt,
					 args->vdso_rt_parked_at,
					 i, args->tgt_vmas, args->nr_vmas))
				goto core_restore_end;
			break;
		}
	}
#endif

	/*
	 * Walk though all VMAs again to drop PROT_WRITE
	 * if it was not there.
	 */
	for (i = 0; i < args->nr_vmas; i++) {
		vma_entry = args->tgt_vmas + i;

		if (!(vma_entry_is(vma_entry, VMA_AREA_REGULAR)))
			continue;

		if (vma_entry_is(vma_entry, VMA_ANON_SHARED)) {
			struct shmem_info *entry;

			entry = find_shmem(args->shmems, args->nr_shmems,
						  vma_entry->shmid);
			if (entry && entry->pid == my_pid &&
			    entry->start == vma_entry->start)
				futex_set_and_wake(&entry->lock, 1);
		}

		if (vma_entry->prot & PROT_WRITE)
			continue;

		sys_mprotect(decode_pointer(vma_entry->start),
			     vma_entry_len(vma_entry),
			     vma_entry->prot);
	}

	/*
	 * Finally restore madivse() bits
	 */
	for (i = 0; i < args->nr_vmas; i++) {
		unsigned long m;

		vma_entry = args->tgt_vmas + i;
		if (!vma_entry->has_madv || !vma_entry->madv)
			continue;

		for (m = 0; m < sizeof(vma_entry->madv) * 8; m++) {
			if (vma_entry->madv & (1ul << m)) {
				ret = sys_madvise(vma_entry->start,
						  vma_entry_len(vma_entry),
						  m);
				if (ret) {
					pr_err("madvise(%"PRIx64", %"PRIu64", %ld) "
					       "failed with %ld\n",
						vma_entry->start,
						vma_entry_len(vma_entry),
						m, ret);
					goto core_restore_end;
				}
			}
		}
	}

	ret = 0;

	/*
	 * Tune up the task fields.
	 */
	ret |= sys_prctl_safe(PR_SET_NAME, (long)args->comm, 0, 0);

	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_CODE,	(long)args->mm.mm_start_code, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_CODE,	(long)args->mm.mm_end_code, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_DATA,	(long)args->mm.mm_start_data, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_END_DATA,	(long)args->mm.mm_end_data, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_STACK,	(long)args->mm.mm_start_stack, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_START_BRK,	(long)args->mm.mm_start_brk, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_BRK,		(long)args->mm.mm_brk, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_START,	(long)args->mm.mm_arg_start, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ARG_END,	(long)args->mm.mm_arg_end, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_START,	(long)args->mm.mm_env_start, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_ENV_END,	(long)args->mm.mm_env_end, 0);
	ret |= sys_prctl_safe(PR_SET_MM, PR_SET_MM_AUXV,	(long)args->mm_saved_auxv, args->mm_saved_auxv_size);
	if (ret)
		goto core_restore_end;

	/*
	 * Because of requirements applied from kernel side
	 * we need to restore /proc/pid/exe symlink late,
	 * after old existing VMAs are superseded with
	 * new ones from image file.
	 */
	ret = restore_self_exe_late(args);
	if (ret)
		goto core_restore_end;

	/*
	 * We need to prepare a valid sigframe here, so
	 * after sigreturn the kernel will pick up the
	 * registers from the frame, set them up and
	 * finally pass execution to the new IP.
	 */
	rt_sigframe = (void *)args->t->mem_zone.rt_sigframe;

	if (restore_thread_common(rt_sigframe, args->t))
		goto core_restore_end;

	/*
	 * Threads restoration. This requires some more comments. This
	 * restorer routine and thread restorer routine has the following
	 * memory map, prepared by a caller code.
	 *
	 * | <-- low addresses                                          high addresses --> |
	 * +-------------------------------------------------------+-----------------------+
	 * | this proc body | own stack | rt_sigframe space | thread restore zone   |
	 * +-------------------------------------------------------+-----------------------+
	 *
	 * where each thread restore zone is the following
	 *
	 * | <-- low addresses                                     high addresses --> |
	 * +--------------------------------------------------------------------------+
	 * | thread restore proc | thread1 stack | thread1 rt_sigframe |
	 * +--------------------------------------------------------------------------+
	 */

	if (args->nr_threads > 1) {
		struct thread_restore_args *thread_args = args->thread_args;
		long clone_flags = CLONE_VM | CLONE_FILES | CLONE_SIGHAND	|
				   CLONE_THREAD | CLONE_SYSVSEM;
		long last_pid_len;
		long parent_tid;
		int i, fd;

		fd = args->fd_last_pid;
		ret = sys_flock(fd, LOCK_EX);
		if (ret) {
			pr_err("Can't lock last_pid %d\n", fd);
			goto core_restore_end;
		}

		for (i = 0; i < args->nr_threads; i++) {
			char last_pid_buf[16], *s;

			/* skip self */
			if (thread_args[i].pid == args->t->pid)
				continue;

			new_sp = restorer_stack(thread_args + i);
			last_pid_len = vprint_num(last_pid_buf, sizeof(last_pid_buf), thread_args[i].pid - 1, &s);
			sys_lseek(fd, 0, SEEK_SET);
			ret = sys_write(fd, s, last_pid_len);
			if (ret < 0) {
				pr_err("Can't set last_pid %ld/%s\n", ret, last_pid_buf);
				goto core_restore_end;
			}

			/*
			 * To achieve functionality like libc's clone()
			 * we need a pure assembly here, because clone()'ed
			 * thread will run with own stack and we must not
			 * have any additional instructions... oh, dear...
			 */

			RUN_CLONE_RESTORE_FN(ret, clone_flags, new_sp, parent_tid, thread_args, args->clone_restore_fn);
		}

		ret = sys_flock(fd, LOCK_UN);
		if (ret) {
			pr_err("Can't unlock last_pid %ld\n", ret);
			goto core_restore_end;
		}

	}

	sys_close(args->fd_last_pid);

	restore_rlims(args);

	ret = create_posix_timers(args);
	if (ret < 0) {
		pr_err("Can't restore posix timers %ld\n", ret);
		goto core_restore_end;
	}

	ret = timerfd_arm(args);
	if (ret < 0) {
		pr_err("Can't restore timerfd %ld\n", ret);
		goto core_restore_end;
	}

	pr_info("%ld: Restored\n", sys_getpid());

	futex_set(&zombies_inprogress, args->nr_zombies);

	restore_finish_stage(CR_STATE_RESTORE);

	futex_wait_while_gt(&zombies_inprogress, 0);

	if (wait_helpers(args) < 0)
		goto core_restore_end;

	ksigfillset(&to_block);
	ret = sys_sigprocmask(SIG_SETMASK, &to_block, NULL, sizeof(k_rtsigset_t));
	if (ret) {
		pr_err("Unable to block signals %ld", ret);
		goto core_restore_end;
	}

	sys_sigaction(SIGCHLD, &args->sigchld_act, NULL, sizeof(k_rtsigset_t));

	ret = restore_signals(args->siginfo, args->siginfo_nr, true);
	if (ret)
		goto core_restore_end;

	ret = restore_signals(args->t->siginfo, args->t->siginfo_nr, false);
	if (ret)
		goto core_restore_end;

	restore_finish_stage(CR_STATE_RESTORE_SIGCHLD);

	rst_tcp_socks_all(args);

	/*
	 * Writing to last-pid is CAP_SYS_ADMIN protected,
	 * turning off TCP repair is CAP_SYS_NED_ADMIN protected,
	 * thus restore* creds _after_ all of the above.
	 */

	ret = restore_creds(&args->creds);
	ret = ret || restore_dumpable_flag(&args->mm);
	ret = ret || restore_pdeath_sig(args->t);

	futex_set_and_wake(&thread_inprogress, args->nr_threads);

	restore_finish_stage(CR_STATE_RESTORE_CREDS);

	if (ret)
		BUG();

	/* Wait until children stop to use args->task_entries */
	futex_wait_while_gt(&thread_inprogress, 1);

	log_set_fd(-1);

	/*
	 * The code that prepared the itimers makes shure the
	 * code below doesn't fail due to bad timing values.
	 */

#define itimer_armed(args, i)				\
		(args->itimers[i].it_interval.tv_sec ||	\
		 args->itimers[i].it_interval.tv_usec)

	if (itimer_armed(args, 0))
		sys_setitimer(ITIMER_REAL, &args->itimers[0], NULL);
	if (itimer_armed(args, 1))
		sys_setitimer(ITIMER_VIRTUAL, &args->itimers[1], NULL);
	if (itimer_armed(args, 2))
		sys_setitimer(ITIMER_PROF, &args->itimers[2], NULL);

	restore_posix_timers(args);

	sys_munmap(args->rst_mem, args->rst_mem_size);

	/*
	 * Sigframe stack.
	 */
	new_sp = (long)rt_sigframe + SIGFRAME_OFFSET;

	/*
	 * Prepare the stack and call for sigreturn,
	 * pure assembly since we don't need any additional
	 * code insns from gcc.
	 */
	rst_sigreturn(new_sp);

core_restore_end:
	futex_abort_and_wake(&task_entries->nr_in_progress);
	pr_err("Restorer fail %ld\n", sys_getpid());
	sys_exit_group(1);
	return -1;
}
Exemplo n.º 18
0
int shutdown_signals()
{
    cleanup_gdb_crash_handler();
    restore_signals();
    return 0;
} //shutdown_signals