1 files changed, 186 insertions, 0 deletions
diff --git a/libs/binder/tests/binderAllocationLimits.cpp b/libs/binder/tests/binderAllocationLimits.cpp
new file mode 100644
index 0000000000..e1f5ed5381
--- /dev/null
+++ b/libs/binder/tests/binderAllocationLimits.cpp
@@ -0,0 +1,186 @@
+/*
+ * Copyright (C) 2020 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 <android-base/logging.h>
+#include <binder/Parcel.h>
+#include <binder/IServiceManager.h>
+#include <gtest/gtest.h>
+#include <utils/CallStack.h>
+
+#include <malloc.h>
+#include <functional>
+#include <vector>
+
+struct DestructionAction {
+    DestructionAction(std::function<void()> f) : mF(std::move(f)) {}
+    ~DestructionAction() { mF(); };
+private:
+    std::function<void()> mF;
+};
+
+// Group of hooks
+struct MallocHooks {
+    decltype(__malloc_hook) malloc_hook;
+    decltype(__realloc_hook) realloc_hook;
+
+    static MallocHooks save() {
+        return {
+            .malloc_hook = __malloc_hook,
+            .realloc_hook = __realloc_hook,
+        };
+    }
+
+    void overwrite() const {
+        __malloc_hook = malloc_hook;
+        __realloc_hook = realloc_hook;
+    }
+};
+
+static const MallocHooks orig_malloc_hooks = MallocHooks::save();
+
+// When malloc is hit, executes lambda.
+namespace LambdaHooks {
+    using AllocationHook = std::function<void(size_t)>;
+    static std::vector<AllocationHook> lambdas = {};
+
+    static void* lambda_realloc_hook(void* ptr, size_t bytes, const void* arg);
+    static void* lambda_malloc_hook(size_t bytes, const void* arg);
+
+    static const MallocHooks lambda_malloc_hooks = {
+        .malloc_hook = lambda_malloc_hook,
+        .realloc_hook = lambda_realloc_hook,
+    };
+
+    static void* lambda_malloc_hook(size_t bytes, const void* arg) {
+        {
+            orig_malloc_hooks.overwrite();
+            lambdas.at(lambdas.size() - 1)(bytes);
+            lambda_malloc_hooks.overwrite();
+        }
+        return orig_malloc_hooks.malloc_hook(bytes, arg);
+    }
+
+    static void* lambda_realloc_hook(void* ptr, size_t bytes, const void* arg) {
+        {
+            orig_malloc_hooks.overwrite();
+            lambdas.at(lambdas.size() - 1)(bytes);
+            lambda_malloc_hooks.overwrite();
+        }
+        return orig_malloc_hooks.realloc_hook(ptr, bytes, arg);
+    }
+
+}
+
+// Action to execute when malloc is hit. Supports nesting. Malloc is not
+// restricted when the allocation hook is being processed.
+__attribute__((warn_unused_result))
+DestructionAction OnMalloc(LambdaHooks::AllocationHook f) {
+    MallocHooks before = MallocHooks::save();
+    LambdaHooks::lambdas.emplace_back(std::move(f));
+    LambdaHooks::lambda_malloc_hooks.overwrite();
+    return DestructionAction([before]() {
+        before.overwrite();
+        LambdaHooks::lambdas.pop_back();
+    });
+}
+
+// exported symbol, to force compiler not to optimize away pointers we set here
+const void* imaginary_use;
+
+TEST(TestTheTest, OnMalloc) {
+    size_t mallocs = 0;
+    {
+        const auto on_malloc = OnMalloc([&](size_t bytes) {
+            mallocs++;
+            EXPECT_EQ(bytes, 40);
+        });
+
+        imaginary_use = new int[10];
+    }
+    EXPECT_EQ(mallocs, 1);
+}
+
+
+__attribute__((warn_unused_result))
+DestructionAction ScopeDisallowMalloc() {
+    return OnMalloc([&](size_t bytes) {
+        ADD_FAILURE() << "Unexpected allocation: " << bytes;
+        using android::CallStack;
+        std::cout << CallStack::stackToString("UNEXPECTED ALLOCATION", CallStack::getCurrent(4 /*ignoreDepth*/).get())
+                  << std::endl;
+    });
+}
+
+using android::IBinder;
+using android::Parcel;
+using android::String16;
+using android::defaultServiceManager;
+using android::sp;
+using android::IServiceManager;
+
+static sp<IBinder> GetRemoteBinder() {
+    // This gets binder representing the service manager
+    // the current IServiceManager API doesn't expose the binder, and
+    // I want to avoid adding usages of the AIDL generated interface it
+    // is using underneath, so to avoid people copying it.
+    sp<IBinder> binder = defaultServiceManager()->checkService(String16("manager"));
+    EXPECT_NE(nullptr, binder);
+    return binder;
+}
+
+TEST(BinderAllocation, ParcelOnStack) {
+    const auto m = ScopeDisallowMalloc();
+    Parcel p;
+    imaginary_use = p.data();
+}
+
+TEST(BinderAllocation, GetServiceManager) {
+    defaultServiceManager(); // first call may alloc
+    const auto m = ScopeDisallowMalloc();
+    defaultServiceManager();
+}
+
+// note, ping does not include interface descriptor
+TEST(BinderAllocation, PingTransaction) {
+    sp<IBinder> a_binder = GetRemoteBinder();
+    const auto m = ScopeDisallowMalloc();
+    a_binder->pingBinder();
+}
+
+TEST(BinderAllocation, SmallTransaction) {
+    String16 empty_descriptor = String16("");
+    sp<IServiceManager> manager = defaultServiceManager();
+
+    size_t mallocs = 0;
+    const auto on_malloc = OnMalloc([&](size_t bytes) {
+        mallocs++;
+        // Parcel should allocate a small amount by default
+        EXPECT_EQ(bytes, 128);
+    });
+    manager->checkService(empty_descriptor);
+
+    EXPECT_EQ(mallocs, 1);
+}
+
+int main(int argc, char** argv) {
+    if (getenv("LIBC_HOOKS_ENABLE") == nullptr) {
+        CHECK(0 == setenv("LIBC_HOOKS_ENABLE", "1", true /*overwrite*/));
+        execv(argv[0], argv);
+        return 1;
+    }
+    ::testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}