1    :  // Copyright 2012 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  
  15    :  #include "syzygy/agent/asan/asan_shadow.h"
  16    :  
  17    :  #include "base/rand_util.h"
  18    :  #include "gtest/gtest.h"
  19    :  #include "syzygy/common/align.h"
  20    :  
  21    :  namespace agent {
  22    :  namespace asan {
  23    :  
  24    :  namespace {
  25    :  
  26    :  // A derived class to expose protected members for unit-testing.
  27    :  class TestShadow : public Shadow {
  28    :   public:
  29    :    using Shadow::Reset;
  30    :    using Shadow::kShadowSize;
  31    :    using Shadow::shadow_;
  32    :  };
  33    :  
  34    :  }  // namespace
  35    :  
  36  E :  TEST(ShadowTest, PoisonUnpoisonAccess) {
  37    :    // Reset the shadow memory.
  38  E :    TestShadow::Reset();
  39  E :    for (size_t i = 0; i < 100; ++i) {
  40    :      // Use a random 8-byte aligned end address.
  41  E :      const size_t size = base::RandInt(1, 16384);
  42    :      const uint8* end_addr =
  43  E :          reinterpret_cast<const uint8*>(base::RandInt(65536, 10*1024*1024) * 8);
  44  E :      const uint8* start_addr = end_addr - size;
  45    :  
  46  E :      for (size_t i = 0; i < size; ++i) {
  47  E :        EXPECT_TRUE(Shadow::IsAccessible(start_addr + i));
  48  E :      }
  49    :  
  50  E :      Shadow::Poison(start_addr, size, Shadow::kHeapNonAccessibleByteMask);
  51  E :      for (size_t i = 0; i < size; ++i)
  52  E :        EXPECT_FALSE(Shadow::IsAccessible(start_addr + i));
  53  E :      EXPECT_TRUE(Shadow::IsAccessible(start_addr - 1));
  54  E :      EXPECT_TRUE(Shadow::IsAccessible(start_addr + size));
  55    :  
  56  E :      const size_t aligned_size = common::AlignUp(size, 8);
  57  E :      const uint8* aligned_start_addr = end_addr - aligned_size;
  58  E :      Shadow::Unpoison(aligned_start_addr, aligned_size);
  59  E :      for (size_t i = 0; i < size; ++i) {
  60  E :        EXPECT_TRUE(Shadow::IsAccessible(start_addr + i));
  61  E :      }
  62  E :    }
  63  E :  }
  64    :  
  65  E :  TEST(ShadowTest, SetUpAndTearDown) {
  66    :    // Reset the shadow memory.
  67  E :    TestShadow::Reset();
  68    :  
  69    :    // Don't check all the shadow bytes otherwise this test will take too much
  70    :    // time.
  71  E :    const size_t kShadowLookupInterval = 25;
  72    :  
  73  E :    intptr_t shadow_array_start = reinterpret_cast<intptr_t>(TestShadow::shadow_);
  74  E :    size_t shadow_start = shadow_array_start >> 3;
  75  E :    size_t shadow_end = shadow_start + (TestShadow::kShadowSize >> 3);
  76    :  
  77  E :    Shadow::SetUp();
  78  E :    for (size_t i = shadow_start; i < shadow_end; i += kShadowLookupInterval) {
  79  E :      ASSERT_EQ(Shadow::kAsanMemoryByte, TestShadow::shadow_[i]);
  80  E :    }
  81  E :    Shadow::TearDown();
  82  E :    for (size_t i = shadow_start; i < shadow_end; i += kShadowLookupInterval) {
  83  E :      ASSERT_EQ(Shadow::kHeapAddressableByte, TestShadow::shadow_[i]);
  84  E :    }
  85  E :  }
  86    :  
  87    :  }  // namespace asan
  88    :  }  // namespace agent