Use isolated namespaces for app native libs

Linker namespaces provide necessary level
of isolation for application native libraries.

The native libraries will no longer be able to
mistakenly depend on platform private libraries
like /system/lib/libssl.so

This change creates one namespace for each instance
of class-loader and uses it when loading native libraries.

For backwards compatibility with older apps we keep
using default namespace and LD_LIBRARY_PATH if target
sdk version is <= 23. (currently set to 0 for testing)

Bug: http://b/22548808
Change-Id: I64e97af7450fbf7e3740ccddda96bb2f7c52e03b

1 files changed, 16 insertions, 8 deletions

diff --git a/runtime/native/java_lang_Runtime.cc b/runtime/native/java_lang_Runtime.cc
index 856a3e7d01..ff82772171 100644
--- a/runtime/native/java_lang_Runtime.cc
+++ b/runtime/native/java_lang_Runtime.cc
@@ -52,10 +52,10 @@ NO_RETURN static void Runtime_nativeExit(JNIEnv*, jclass, jint status) {
   exit(status);
 }
 
-static void SetLdLibraryPath(JNIEnv* env, jstring javaLdLibraryPathJstr) {
+static void SetLdLibraryPath(JNIEnv* env, jstring javaLdLibraryPath) {
 #ifdef __ANDROID__
-  if (javaLdLibraryPathJstr != nullptr) {
-    ScopedUtfChars ldLibraryPath(env, javaLdLibraryPathJstr);
+  if (javaLdLibraryPath != nullptr) {
+    ScopedUtfChars ldLibraryPath(env, javaLdLibraryPath);
     if (ldLibraryPath.c_str() != nullptr) {
       android_update_LD_LIBRARY_PATH(ldLibraryPath.c_str());
     }
@@ -63,23 +63,31 @@ static void SetLdLibraryPath(JNIEnv* env, jstring javaLdLibraryPathJstr) {
 
 #else
   LOG(WARNING) << "android_update_LD_LIBRARY_PATH not found; .so dependencies will not work!";
-  UNUSED(javaLdLibraryPathJstr, env);
+  UNUSED(javaLdLibraryPath, env);
 #endif
 }
 
 static jstring Runtime_nativeLoad(JNIEnv* env, jclass, jstring javaFilename, jobject javaLoader,
-                                  jstring javaLdLibraryPathJstr) {
+                                  jstring javaLdLibraryPath, jstring javaIsolationPath) {
   ScopedUtfChars filename(env, javaFilename);
   if (filename.c_str() == nullptr) {
     return nullptr;
   }
 
-  SetLdLibraryPath(env, javaLdLibraryPathJstr);
+  int32_t target_sdk_version = Runtime::Current()->GetTargetSdkVersion();
+
+  // Starting with N nativeLoad uses classloader local
+  // linker namespace instead of global LD_LIBRARY_PATH
+  // (23 is Marshmallow)
+  if (target_sdk_version == 0) {
+    SetLdLibraryPath(env, javaLdLibraryPath);
+  }
 
   std::string error_msg;
   {
     JavaVMExt* vm = Runtime::Current()->GetJavaVM();
-    bool success = vm->LoadNativeLibrary(env, filename.c_str(), javaLoader, &error_msg);
+    bool success = vm->LoadNativeLibrary(env, filename.c_str(), javaLoader,
+                                         javaLdLibraryPath, javaIsolationPath, &error_msg);
     if (success) {
       return nullptr;
     }
@@ -107,7 +115,7 @@ static JNINativeMethod gMethods[] = {
   NATIVE_METHOD(Runtime, gc, "()V"),
   NATIVE_METHOD(Runtime, maxMemory, "!()J"),
   NATIVE_METHOD(Runtime, nativeExit, "(I)V"),
-  NATIVE_METHOD(Runtime, nativeLoad, "(Ljava/lang/String;Ljava/lang/ClassLoader;Ljava/lang/String;)Ljava/lang/String;"),
+  NATIVE_METHOD(Runtime, nativeLoad, "(Ljava/lang/String;Ljava/lang/ClassLoader;Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;"),
   NATIVE_METHOD(Runtime, totalMemory, "!()J"),
 };