Accept non-fatal resource exceptions without generating crash reports

util/mach/exception_types_test.cc

+// Copyright 2015 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "util/mach/exception_types.h"
+
+#include <kern/exc_resource.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "base/basictypes.h"
+#include "base/strings/stringprintf.h"
+#include "gtest/gtest.h"
+#include "util/mac/mac_util.h"
+#include "util/mach/mach_extensions.h"
+
+namespace crashpad {
+namespace test {
+namespace {
+
+TEST(ExceptionTypes, ExcCrashRecoverOriginalException) {
+  struct TestData {
+    mach_exception_code_t code_0;
+    exception_type_t exception;
+    mach_exception_code_t original_code_0;
+    int signal;
+  };
+  const TestData kTestData[] = {
+      {0xb100001, EXC_BAD_ACCESS, KERN_INVALID_ADDRESS, SIGSEGV},
+      {0xb100002, EXC_BAD_ACCESS, KERN_PROTECTION_FAILURE, SIGSEGV},
+      {0xa100002, EXC_BAD_ACCESS, KERN_PROTECTION_FAILURE, SIGBUS},
+      {0x4200001, EXC_BAD_INSTRUCTION, 1, SIGILL},
+      {0x8300001, EXC_ARITHMETIC, 1, SIGFPE},
+      {0x5600002, EXC_BREAKPOINT, 2, SIGTRAP},
+      {0x3000000, 0, 0, SIGQUIT},
+      {0x6000000, 0, 0, SIGABRT},
+      {0xc000000, 0, 0, SIGSYS},
+      {0, 0, 0, 0},
+  };
+
+  for (size_t index = 0; index < arraysize(kTestData); ++index) {
+    const TestData& test_data = kTestData[index];
+    SCOPED_TRACE(base::StringPrintf(
+        "index %zu, code_0 0x%llx", index, test_data.code_0));
+
+    mach_exception_code_t original_code_0;
+    int signal;
+    exception_type_t exception = ExcCrashRecoverOriginalException(
+        test_data.code_0, &original_code_0, &signal);
+
+    EXPECT_EQ(test_data.exception, exception);
+    EXPECT_EQ(test_data.original_code_0, original_code_0);
+    EXPECT_EQ(test_data.signal, signal);
+  }
+
+  // Now make sure that ExcCrashRecoverOriginalException() properly ignores
+  // optional arguments.
+  static_assert(arraysize(kTestData) >= 1, "must have something to test");
+  const TestData& test_data = kTestData[0];
+  EXPECT_EQ(
+      test_data.exception,
+      ExcCrashRecoverOriginalException(test_data.code_0, nullptr, nullptr));
+
+  mach_exception_code_t original_code_0;
+  EXPECT_EQ(test_data.exception,
+            ExcCrashRecoverOriginalException(
+                test_data.code_0, &original_code_0, nullptr));
+  EXPECT_EQ(test_data.original_code_0, original_code_0);
+
+  int signal;
+  EXPECT_EQ(
+      test_data.exception,
+      ExcCrashRecoverOriginalException(test_data.code_0, nullptr, &signal));
+  EXPECT_EQ(test_data.signal, signal);
+}
+
+// These macros come from the #ifdef KERNEL section of <kern/exc_resource.h>:
+// 10.10 xnu-2782.1.97/osfmk/kern/exc_resource.h.
+#define EXC_RESOURCE_ENCODE_TYPE(code, type) \
+  ((code) |= ((static_cast<uint64_t>(type) & 0x7ull) << 61))
+#define EXC_RESOURCE_ENCODE_FLAVOR(code, flavor) \
+  ((code) |= ((static_cast<uint64_t>(flavor) & 0x7ull) << 58))
+
+TEST(ExceptionTypes, IsExceptionNonfatalResource) {
+  const pid_t pid = getpid();
+
+  mach_exception_code_t code = 0;
+  EXC_RESOURCE_ENCODE_TYPE(code, RESOURCE_TYPE_CPU);
+  EXC_RESOURCE_ENCODE_FLAVOR(code, FLAVOR_CPU_MONITOR);
+  EXPECT_TRUE(IsExceptionNonfatalResource(EXC_RESOURCE, code, pid));
+
+  if (MacOSXMinorVersion() >= 10) {
+    // FLAVOR_CPU_MONITOR_FATAL was introduced in Mac OS X 10.10.
+    code = 0;
+    EXC_RESOURCE_ENCODE_TYPE(code, RESOURCE_TYPE_CPU);
+    EXC_RESOURCE_ENCODE_FLAVOR(code, FLAVOR_CPU_MONITOR_FATAL);
+    EXPECT_FALSE(IsExceptionNonfatalResource(EXC_RESOURCE, code, pid));
+  }
+
+  // This assumes that WAKEMON_MAKE_FATAL is not set for this process. The
+  // default is for WAKEMON_MAKE_FATAL to not be set, there’s no public API to
+  // enable it, and nothing in this process should have enabled it.
+  code = 0;
+  EXC_RESOURCE_ENCODE_TYPE(code, RESOURCE_TYPE_WAKEUPS);
+  EXC_RESOURCE_ENCODE_FLAVOR(code, FLAVOR_WAKEUPS_MONITOR);
+  EXPECT_TRUE(IsExceptionNonfatalResource(EXC_RESOURCE, code, pid));
+
+  code = 0;
+  EXC_RESOURCE_ENCODE_TYPE(code, RESOURCE_TYPE_MEMORY);
+  EXC_RESOURCE_ENCODE_FLAVOR(code, FLAVOR_HIGH_WATERMARK);
+  EXPECT_TRUE(IsExceptionNonfatalResource(EXC_RESOURCE, code, pid));
+
+  // Non-EXC_RESOURCE exceptions should never be considered nonfatal resource
+  // exceptions, because they aren’t resource exceptions at all.
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_CRASH, 0xb100001, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_CRASH, 0x0b00000, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_CRASH, 0x6000000, pid));
+  EXPECT_FALSE(
+      IsExceptionNonfatalResource(EXC_BAD_ACCESS, KERN_INVALID_ADDRESS, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_BAD_INSTRUCTION, 1, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_ARITHMETIC, 1, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(EXC_BREAKPOINT, 2, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(0, 0, pid));
+  EXPECT_FALSE(IsExceptionNonfatalResource(kMachExceptionSimulated, 0, pid));
+}
+
+}  // namespace
+}  // namespace test
+}  // namespace crashpad