Dynamic loading: Fill pages with halts only when they are needed

src/native_client/tests/dynamic_code_loading/nacl.scons

 # -*- python -*-
 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 Import('env')
 
 # The test works with PNaCl-ARM but not with PNaCl-x86, because the
 # assembler #defines __arm__ rather than __i386__ or __x86_64__ even
 # when we are targetting x86.
@@ skipping 66 matching lines @@
 
 prog_env.ComponentProgram('dyncode_disabled_test.nexe',
                           ['dyncode_disabled_test.c'],
                           EXTRA_LIBS=['nacl_dyncode'])
 
 prog_env.ComponentProgram('debug_mode_test.nexe',
                           ['debug_mode_test.c',
                            template_obj],
                           EXTRA_LIBS=['nacl_dyncode'])
 
+prog_env.ComponentProgram('dyncode_demand_alloc_test.nexe',
+                          ['dyncode_demand_alloc_test.c'],
+                          EXTRA_LIBS=['nacl_dyncode'])
+
 tests = [
     prog_env.CommandSelLdrTestNacl(
         'dynamic_load_test.out',
         command=[dynamic_load_test_nexe],
         # We need to set this because the test needs to behave
         # differently in the plugin, but the plugin does not provide a
         # way to distinguish itself.  TODO(mseaborn): Fix that.
         # See http://code.google.com/p/nativeclient/issues/detail?id=889
         sel_ldr_flags=['-E', 'NACL_SRPC_STANDALONE=1'],
         ),
     prog_env.CommandSelLdrTestNacl(
         'write_to_dyncode.out',
         command=[prog_env.File('write_to_dyncode.nexe')],
         exit_status='untrusted_segfault',
         stdout_golden=prog_env.File('write_to_dyncode.stdout'),
         ),
     prog_env.CommandSelLdrTestNacl(
         'dyncode_disabled_test.out',
         command=[prog_env.File('dyncode_disabled_test.nexe')],
         osenv='NACL_DISABLE_DYNAMIC_LOADING=1',
         ),
     prog_env.CommandSelLdrTestNacl(
         'debug_mode_test.out',
         # NOTE: the data we are loading does not pass the validator
         sel_ldr_flags=["-c"],
         command=[prog_env.File('debug_mode_test.nexe')],
         ),
+    # This tests, from untrusted code, that dyncode pages are
+    # inaccessible before they are allocated.
+    prog_env.CommandSelLdrTestNacl(
+        'dyncode_demand_alloc_test.out',
+        command=[prog_env.File('dyncode_demand_alloc_test.nexe')],
+        exit_status='untrusted_segfault',
+        stdout_golden=prog_env.File('dyncode_demand_alloc_test.stdout'),
+        ),
   ]
 if not prog_env.Bit('target_arm'):
   tests.append(prog_env.CommandSelLdrTestNacl(
        'dynamic_modify_test.out',
        command=[dynamic_modify_test_nexe],
        sel_ldr_flags=['-E', 'NACL_SRPC_STANDALONE=1']))
 
 # TODO(kcc): non-standard linking options confuse Valgrind debug info reader.
 # See http://code.google.com/p/nativeclient/issues/detail?id=1606
 is_broken = prog_env.IsRunningUnderValgrind()
 prog_env.AddNodeToTestSuite(tests,
                             ['small_tests', 'sel_ldr_tests'],
                             'run_dynamic_load_test',
                             is_broken=is_broken)