Merge "Support loading libraries to a reserved address."

3 files changed, 192 insertions, 0 deletions

diff --git a/tests/Android.mk b/tests/Android.mk
index 723d7cf..d2bcce8 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -190,6 +190,18 @@ include $(LOCAL_PATH)/Android.build.mk
 endif
 
 # -----------------------------------------------------------------------------
+# Library used by dlext tests.
+# -----------------------------------------------------------------------------
+libdlext_test_src_files := \
+    dlext_test_library.cpp \
+
+module := libdlext_test
+module_tag := optional
+build_type := target
+build_target := SHARED_LIBRARY
+include $(LOCAL_PATH)/Android.build.mk
+
+# -----------------------------------------------------------------------------
 # Tests for the device using bionic's .so. Run with:
 #   adb shell /data/nativetest/bionic-unit-tests/bionic-unit-tests
 # -----------------------------------------------------------------------------
@@ -197,6 +209,7 @@ bionic-unit-tests_whole_static_libraries := \
     libBionicTests \
 
 bionic-unit-tests_src_files := \
+    dlext_test.cpp \
     dlfcn_test.cpp \
 
 bionic-unit-tests_ldflags := \
diff --git a/tests/dlext_test.cpp b/tests/dlext_test.cpp
new file mode 100644
index 0000000..299b408
--- /dev/null
+++ b/tests/dlext_test.cpp
@@ -0,0 +1,136 @@
+/*
+ * Copyright (C) 2014 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 <gtest/gtest.h>
+
+#include <dlfcn.h>
+#include <android/dlext.h>
+#include <sys/mman.h>
+
+
+#define ASSERT_DL_NOTNULL(ptr) \
+    ASSERT_TRUE(ptr != NULL) << "dlerror: " << dlerror()
+
+#define ASSERT_DL_ZERO(i) \
+    ASSERT_EQ(0, i) << "dlerror: " << dlerror()
+
+
+typedef int (*fn)(void);
+#define LIBNAME "libdlext_test.so"
+#define LIBSIZE 1024*1024 // how much address space to reserve for it
+
+
+class DlExtTest : public ::testing::Test {
+protected:
+  virtual void SetUp() {
+    handle_ = NULL;
+    // verify that we don't have the library loaded already
+    ASSERT_EQ(NULL, dlsym(RTLD_DEFAULT, "getRandomNumber"));
+    // call dlerror() to swallow the error, and check it was the one we wanted
+    ASSERT_STREQ("undefined symbol: getRandomNumber", dlerror());
+  }
+
+  virtual void TearDown() {
+    if (handle_ != NULL) {
+      ASSERT_DL_ZERO(dlclose(handle_));
+    }
+  }
+
+  void* handle_;
+};
+
+TEST_F(DlExtTest, ExtInfoNull) {
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, NULL);
+  ASSERT_DL_NOTNULL(handle_);
+  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+  ASSERT_DL_NOTNULL(f);
+  EXPECT_EQ(4, f());
+}
+
+TEST_F(DlExtTest, ExtInfoNoFlags) {
+  android_dlextinfo extinfo;
+  extinfo.flags = 0;
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
+  ASSERT_DL_NOTNULL(handle_);
+  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+  ASSERT_DL_NOTNULL(f);
+  EXPECT_EQ(4, f());
+}
+
+TEST_F(DlExtTest, Reserved) {
+  void* start = mmap(NULL, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
+                     -1, 0);
+  ASSERT_TRUE(start != MAP_FAILED);
+  android_dlextinfo extinfo;
+  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
+  extinfo.reserved_addr = start;
+  extinfo.reserved_size = LIBSIZE;
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
+  ASSERT_DL_NOTNULL(handle_);
+  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+  ASSERT_DL_NOTNULL(f);
+  EXPECT_GE(f, start);
+  EXPECT_LT(reinterpret_cast<void*>(f),
+            reinterpret_cast<char*>(start) + LIBSIZE);
+  EXPECT_EQ(4, f());
+}
+
+TEST_F(DlExtTest, ReservedTooSmall) {
+  void* start = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
+                     -1, 0);
+  ASSERT_TRUE(start != MAP_FAILED);
+  android_dlextinfo extinfo;
+  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
+  extinfo.reserved_addr = start;
+  extinfo.reserved_size = PAGE_SIZE;
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
+  EXPECT_EQ(NULL, handle_);
+}
+
+TEST_F(DlExtTest, ReservedHint) {
+  void* start = mmap(NULL, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
+                     -1, 0);
+  ASSERT_TRUE(start != MAP_FAILED);
+  android_dlextinfo extinfo;
+  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
+  extinfo.reserved_addr = start;
+  extinfo.reserved_size = LIBSIZE;
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
+  ASSERT_DL_NOTNULL(handle_);
+  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+  ASSERT_DL_NOTNULL(f);
+  EXPECT_GE(f, start);
+  EXPECT_LT(reinterpret_cast<void*>(f),
+            reinterpret_cast<char*>(start) + LIBSIZE);
+  EXPECT_EQ(4, f());
+}
+
+TEST_F(DlExtTest, ReservedHintTooSmall) {
+  void* start = mmap(NULL, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
+                     -1, 0);
+  ASSERT_TRUE(start != MAP_FAILED);
+  android_dlextinfo extinfo;
+  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
+  extinfo.reserved_addr = start;
+  extinfo.reserved_size = PAGE_SIZE;
+  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
+  ASSERT_DL_NOTNULL(handle_);
+  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
+  ASSERT_DL_NOTNULL(f);
+  EXPECT_TRUE(f < start || (reinterpret_cast<void*>(f) >=
+                            reinterpret_cast<char*>(start) + PAGE_SIZE));
+  EXPECT_EQ(4, f());
+}
diff --git a/tests/dlext_test_library.cpp b/tests/dlext_test_library.cpp
new file mode 100644
index 0000000..5c04329
--- /dev/null
+++ b/tests/dlext_test_library.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2014 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.
+ */
+
+class A {
+public:
+  virtual int getRandomNumber() {
+    return 4;  // chosen by fair dice roll.
+               // guaranteed to be random.
+  }
+
+  virtual ~A() {}
+};
+
+A a;
+
+// nested macros to make it easy to define a large amount of read-only data
+// which will require relocation.
+#define A_16 &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a, &a,
+#define A_128 A_16 A_16 A_16 A_16 A_16 A_16 A_16 A_16
+#define A_1024 A_128 A_128 A_128 A_128 A_128 A_128 A_128 A_128
+
+extern "C" A* const lots_of_relro[] = {
+  A_1024 A_1024 A_1024 A_1024 A_1024 A_1024 A_1024 A_1024
+};
+
+extern "C" int getRandomNumber() {
+  // access the relro section (twice, in fact, once for the pointer, and once
+  // for the vtable of A) to check it's actually there.
+  return lots_of_relro[0]->getRandomNumber();
+}