1 files changed, 110 insertions, 0 deletions
diff --git a/libartbase/base/safe_copy_test.cc b/libartbase/base/safe_copy_test.cc
new file mode 100644
index 0000000000..a9ec9528a1
--- /dev/null
+++ b/libartbase/base/safe_copy_test.cc
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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 "safe_copy.h"
+
+#include "common_runtime_test.h"
+
+#include <errno.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/user.h>
+
+#include "globals.h"
+
+namespace art {
+
+#if defined(__linux__)
+
+TEST(SafeCopyTest, smoke) {
+  DCHECK_EQ(kPageSize, static_cast<decltype(kPageSize)>(PAGE_SIZE));
+
+  // Map four pages, mark the second one as PROT_NONE, unmap the last one.
+  void* map = mmap(nullptr, kPageSize * 4, PROT_READ | PROT_WRITE,
+                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  ASSERT_NE(MAP_FAILED, map);
+  char* page1 = static_cast<char*>(map);
+  char* page2 = page1 + kPageSize;
+  char* page3 = page2 + kPageSize;
+  char* page4 = page3 + kPageSize;
+  ASSERT_EQ(0, mprotect(page1 + kPageSize, kPageSize, PROT_NONE));
+  ASSERT_EQ(0, munmap(page4, kPageSize));
+
+  page1[0] = 'a';
+  page1[kPageSize - 1] = 'z';
+
+  page3[0] = 'b';
+  page3[kPageSize - 1] = 'y';
+
+  char buf[kPageSize];
+
+  // Completely valid read.
+  memset(buf, 0xCC, sizeof(buf));
+  EXPECT_EQ(static_cast<ssize_t>(kPageSize), SafeCopy(buf, page1, kPageSize)) << strerror(errno);
+  EXPECT_EQ(0, memcmp(buf, page1, kPageSize));
+
+  // Reading into a guard page.
+  memset(buf, 0xCC, sizeof(buf));
+  EXPECT_EQ(static_cast<ssize_t>(kPageSize - 1), SafeCopy(buf, page1 + 1, kPageSize));
+  EXPECT_EQ(0, memcmp(buf, page1 + 1, kPageSize - 1));
+
+  // Reading from a guard page into a real page.
+  memset(buf, 0xCC, sizeof(buf));
+  EXPECT_EQ(0, SafeCopy(buf, page2 + kPageSize - 1, kPageSize));
+
+  // Reading off of the end of a mapping.
+  memset(buf, 0xCC, sizeof(buf));
+  EXPECT_EQ(static_cast<ssize_t>(kPageSize), SafeCopy(buf, page3, kPageSize * 2));
+  EXPECT_EQ(0, memcmp(buf, page3, kPageSize));
+
+  // Completely invalid.
+  EXPECT_EQ(0, SafeCopy(buf, page1 + kPageSize, kPageSize));
+
+  // Clean up.
+  ASSERT_EQ(0, munmap(map, kPageSize * 3));
+}
+
+TEST(SafeCopyTest, alignment) {
+  DCHECK_EQ(kPageSize, static_cast<decltype(kPageSize)>(PAGE_SIZE));
+
+  // Copy the middle of a mapping to the end of another one.
+  void* src_map = mmap(nullptr, kPageSize * 3, PROT_READ | PROT_WRITE,
+                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  ASSERT_NE(MAP_FAILED, src_map);
+
+  // Add a guard page to make sure we don't write past the end of the mapping.
+  void* dst_map = mmap(nullptr, kPageSize * 4, PROT_READ | PROT_WRITE,
+                       MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  ASSERT_NE(MAP_FAILED, dst_map);
+
+  char* src = static_cast<char*>(src_map);
+  char* dst = static_cast<char*>(dst_map);
+  ASSERT_EQ(0, mprotect(dst + 3 * kPageSize, kPageSize, PROT_NONE));
+
+  src[512] = 'a';
+  src[kPageSize * 3 - 512 - 1] = 'z';
+
+  EXPECT_EQ(static_cast<ssize_t>(kPageSize * 3 - 1024),
+            SafeCopy(dst + 1024, src + 512, kPageSize * 3 - 1024));
+  EXPECT_EQ(0, memcmp(dst + 1024, src + 512, kPageSize * 3 - 1024));
+
+  ASSERT_EQ(0, munmap(src_map, kPageSize * 3));
+  ASSERT_EQ(0, munmap(dst_map, kPageSize * 4));
+}
+
+#endif  // defined(__linux__)
+
+}  // namespace art