Disable the signal handlers set by AddressSanitizer.

src/trusted/service_runtime/sel_main_chrome.c

 /*
  * Copyright (c) 2012 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.
  */
 
 #include "native_client/src/trusted/service_runtime/sel_main_chrome.h"
 
 #include "native_client/src/include/portability.h"
 #include "native_client/src/include/portability_io.h"
@@ skipping 15 matching lines @@
 #include "native_client/src/trusted/service_runtime/nacl_globals.h"
 #include "native_client/src/trusted/service_runtime/env_cleanser.h"
 #include "native_client/src/trusted/service_runtime/nacl_app.h"
 #include "native_client/src/trusted/service_runtime/nacl_all_modules.h"
 #include "native_client/src/trusted/service_runtime/nacl_signal.h"
 #include "native_client/src/trusted/service_runtime/osx/mach_exception_handler.h"
 #include "native_client/src/trusted/service_runtime/sel_ldr.h"
 #include "native_client/src/trusted/service_runtime/sel_qualify.h"
 #include "native_client/src/trusted/service_runtime/win/exception_patch/ntdll_patch.h"
 
+#ifdef ADDRESS_SANITIZER

[Mark Seaborn, 2012/04/19 16:16:39]

Can you add a comment to explain what this is for, please?

I suspect we also want a TODO in here to say that when NaCl's signal handler is
enabled by default on Linux, we should replace this.  This is what we'd do:

 * NaCl's signal handler should run first;
 * when NaCl's signal handler notices the crash was in trusted code, it passes
control to the previously-registered ASAN signal handler.

Does that match what you'd expect?

What happens on Mac OS X, though?  Does ASAN still use a signal handler, and how
does it interact with Mac Breakpad's use of Mach exception handling?

+extern __asan_disable_signal_handlers();

[Mark Seaborn, 2012/04/19 16:16:39]

Surely "void __asan_disable_signal_handlers(void);"?  'extern' is redundant on
function prototypes (and IIRC our presubmit scripts reject it?).

Is there not a header file we can #include to get this?

+#endif
+
 static int const kSrpcFd = 5;
 
 struct NaClChromeMainArgs *NaClChromeMainArgsCreate(void) {
   struct NaClChromeMainArgs *args = malloc(sizeof(*args));
   if (args == NULL)
     return NULL;
   args->imc_bootstrap_handle = NACL_INVALID_HANDLE;
   args->irt_fd = -1;
   args->enable_exception_handling = 0;
   args->enable_debug_stub = 0;
@@ skipping 94 matching lines @@
   NaClAddImcHandle(nap, args->imc_bootstrap_handle, export_addr_to);
 
   /*
    * in order to report load error to the browser plugin through the
    * secure command channel, we do not immediate jump to cleanup code
    * on error.  rather, we continue processing (assuming earlier
    * errors do not make it inappropriate) until the secure command
    * channel is set up, and then bail out.
    */
 
+#ifdef ADDRESS_SANITIZER
+  __asan_disable_signal_handlers();

[Mark Seaborn, 2012/04/19 16:16:39]

Can you add a comment to explain what this is for, please?

I suspect we also want a TODO in here to say that when NaCl's signal handler is
enabled by default on Linux, we should replace this.  This is what we'd do:

 * NaCl's signal handler should run first;
 * when NaCl's signal handler notices the crash was in trusted code, it passes
control to the previously-registered ASAN signal handler.

Does that match what you'd expect?

What happens on Mac OS X, though?  Does ASAN still use a signal handler, and how
does it interact with Mac Breakpad's use of Mach exception handling?

+#endif
   /*
    * Ensure this operating system platform is supported.
    */
   skip_qualification = getenv("NACL_DANGEROUS_SKIP_QUALIFICATION_TEST") != NULL;
   if (skip_qualification) {
     fprintf(stderr, "PLATFORM QUALIFICATION DISABLED - "
         "Native Client's sandbox will be unreliable!\n");
   } else {
     errcode = NACL_FI_VAL("pq", NaClErrorCode,
                           NaClRunSelQualificationTests());
@@ skipping 155 matching lines @@
   if (LOAD_OK != errcode) {
     NaClBlockIfCommandChannelExists(nap);
   }
 
  done_ctor:
 
   NaClAllModulesFini();
 
   NaClExit(ret_code);
 }