[cfi] Test cross-dso CFI on Android.

[eugenis]

compiler-rt/test/lit.common.cfg

214

This could be a bit excessive...
It would add ~13 new features, and we currently only use one (android-26). AFAIK, lit does not allow numeric comparisons in UNSUPPORTED and REQUIRES headers.

[pcc]

compiler-rt/test/lit.common.cfg

214

I'd prefer to make this define only android-26 if the version is >=26, as that should make life easier for someone who is trying to figure out where android-26 is coming from. If we need more versions, we could perhaps figure something else out.

[eugenis]

remove extra features

[pcc]

compiler-rt/test/cfi/lit.cfg

43

Is this substitution being used?

compiler-rt/test/lit.common.cfg

215

Remove semicolon

[eugenis]

removed a semicolon

[eugenis]

removed an unused substitution

[pcc]

LGTM

compiler-rt/test/cfi/cross-dso/lit.local.cfg

 def getRoot(config):
   if not config.parent:
     return config
   return getRoot(config.parent)
 
 root = getRoot(config)
 
-if root.host_os not in ['Linux'] or config.android:
+if root.host_os not in ['Linux']:
+  config.unsupported = True
+
+# Android O (API level 26) has support for cross-dso cfi in libdl.so.
+if config.android and 'android-26' not in config.available_features:
   config.unsupported = True

compiler-rt/test/cfi/cross-dso/shadow_is_read_only.cpp

 // RUN: %clangxx_cfi_dso -std=c++11 -g -DSHARED_LIB %s -fPIC -shared -o %t-cfi-so.so
 // RUN: %clangxx -std=c++11 -g -DSHARED_LIB %s -fPIC -shared -o %t-nocfi-so.so
 // RUN: %clangxx_cfi_dso -std=c++11 -g %s -o %t
 
 // RUN: %expect_crash %t start 2>&1 | FileCheck %s
 // RUN: %expect_crash %t mmap 2>&1 | FileCheck %s
 // RUN: %expect_crash %t dlopen %t-cfi-so.so 2>&1 | FileCheck %s
 // RUN: %expect_crash %t dlclose %t-cfi-so.so 2>&1 | FileCheck %s
 // RUN: %expect_crash %t dlopen %t-nocfi-so.so 2>&1 | FileCheck %s
 // RUN: %expect_crash %t dlclose %t-nocfi-so.so 2>&1 | FileCheck %s
 
 // Tests that shadow is read-only most of the time.
 // REQUIRES: cxxabi
 
+// Uses private API that is not available on Android.
+// UNSUPPORTED: android
+
 #include <assert.h>
 #include <dlfcn.h>
 #include <stdio.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/mman.h>
 

compiler-rt/test/cfi/cross-dso/stats.cpp

 // RUN: %clangxx_cfi_dso -DSHARED_LIB -fPIC -g -fsanitize-stats -shared -o %t.so %s
 // RUN: %clangxx_cfi_dso -g -fsanitize-stats -o %t %s %t.so
 // RUN: env SANITIZER_STATS_PATH=%t.stats %t
 // RUN: sanstats %t.stats | FileCheck %s
 
 // CFI-icall is not implemented in thinlto mode => ".cfi" suffixes are missing
 // in sanstats output.
 
+// FIXME: %t.stats must be transferred from device to host for this to work on Android.
+// XFAIL: android
+
 struct ABase {};
 
 struct A : ABase {
   virtual void vf() {}
   void nvf() {}
 };
 
 extern "C" void vcall(A *a);

compiler-rt/test/cfi/cross-dso/util/cfi_stubs.h

+// This is a hack to access CFI interface that Android has in libdl.so on
+// device, but not in the NDK.
+#include <dlfcn.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+typedef void (*cfi_slowpath_ty)(uint64_t, void *);
+typedef void (*cfi_slowpath_diag_ty)(uint64_t, void *, void *);
+
+static cfi_slowpath_ty cfi_slowpath;
+static cfi_slowpath_diag_ty cfi_slowpath_diag;
+
+__attribute__((constructor(0), no_sanitize("cfi"))) static void init() {
+  cfi_slowpath = (cfi_slowpath_ty)dlsym(RTLD_NEXT, "__cfi_slowpath");
+  cfi_slowpath_diag =
+      (cfi_slowpath_diag_ty)dlsym(RTLD_NEXT, "__cfi_slowpath_diag");
+  if (!cfi_slowpath || !cfi_slowpath_diag) abort();
+}
+
+extern "C" {
+__attribute__((visibility("hidden"), no_sanitize("cfi"))) void __cfi_slowpath(
+    uint64_t Type, void *Addr) {
+  cfi_slowpath(Type, Addr);
+}
+
+__attribute__((visibility("hidden"), no_sanitize("cfi"))) void
+__cfi_slowpath_diag(uint64_t Type, void *Addr, void *Diag) {
+  cfi_slowpath_diag(Type, Addr, Diag);
+}
+}

compiler-rt/test/cfi/lit.cfg

if config.cfi_lit_test_mode == "Devirt":
     config.substitutions.append((r"%expect_crash_unless_devirt ", ""))
   else:
     config.substitutions.append((r"%expect_crash_unless_devirt ", config.expect_crash))
 
   cxx = ' '.join(config.cxx_mode_flags) + ' '
   diag = '-fno-sanitize-trap=cfi -fsanitize-recover=cfi '
   non_dso = '-fvisibility=hidden '
   dso = '-fsanitize-cfi-cross-dso -fvisibility=default '
+  if config.android:
+    dso += '-include ' + config.test_source_root + '/cross-dso/util/cfi_stubs.h '
   config.substitutions.append((r"%clang_cfi ", clang_cfi + non_dso))
   config.substitutions.append((r"%clangxx_cfi ", clang_cfi + cxx + non_dso))
   config.substitutions.append((r"%clang_cfi_diag ", clang_cfi + non_dso + diag))
   config.substitutions.append((r"%clangxx_cfi_diag ", clang_cfi + cxx + non_dso + diag))
   config.substitutions.append((r"%clangxx_cfi_dso ", clang_cfi + cxx + dso))
   config.substitutions.append((r"%clangxx_cfi_dso_diag ", clang_cfi + cxx + dso + diag))
 else:
   config.unsupported = True
 
+default_ubsan_opts_str = ':'.join(config.default_sanitizer_opts)
+if default_ubsan_opts_str:
+  config.environment['UBSAN_OPTIONS'] = default_ubsan_opts_str
+  default_ubsan_opts_str += ':'
+# Substitution to setup UBSAN_OPTIONS in portable way.
+config.substitutions.append(('%env_ubsan_opts=',
+                             'env UBSAN_OPTIONS=' + default_ubsan_opts_str))
+
 if lit_config.params.get('check_supported', None) and config.unsupported:
   raise BaseException("Tests unsupported")

compiler-rt/test/lit.common.cfg

if output_re:
         config.available_features.add('x86_64h')
   except:
     pass
 
   config.substitutions.append( ("%macos_min_target_10_11", "-mmacosx-version-min=10.11") )
 else:
   config.substitutions.append( ("%macos_min_target_10_11", "") )
 
+if config.android:
+  adb = os.environ.get('ADB', 'adb')
+  try:
+    android_api_level_str = subprocess.check_output([adb, "shell", "getprop", "ro.build.version.sdk"]).rstrip()
+  except (subprocess.CalledProcessError, OSError):
+    lit_config.fatal("Failed to read ro.build.version.sdk (using '%s' as adb)" % adb)
+  try:
+    android_api_level = int(android_api_level_str)
+  except ValueError:
+    lit_config.fatal("Failed to read ro.build.version.sdk (using '%s' as adb): got '%s'" % (adb, android_api_level_str))
+  if android_api_level >= 26:
+    config.available_features.add('android-26')
+
 sancovcc_path = os.path.join(config.llvm_tools_dir, "sancov")
 if os.path.exists(sancovcc_path):
   config.available_features.add("has_sancovcc")
   config.substitutions.append( ("%sancovcc ", sancovcc_path) )
 
 def is_darwin_lto_supported():
   return os.path.exists(os.path.join(config.llvm_shlib_dir, 'libLTO.dylib'))