libgui: Add test for OOB slot number in dequeue

Adds a unit test that verifies that a malicious BnGraphicBufferProducer
cannot pass an invalid slot number to a Surface and thus cause the
Surface to segfault (or otherwise access out-of-bounds memory).

Bug: 36991414
Test: The new Malicious* tests pass after applying the security patch
Change-Id: I2083465a496cfcc8e8c3b3bc288f5f6904005ac3

diff --git a/libs/gui/tests/Android.bp b/libs/gui/tests/Android.bp
index 192bfc8..7efdb14 100644 (file)
--- a/libs/gui/tests/Android.bp
+++ b/libs/gui/tests/Android.bp
@@ -14,6 +14,7 @@ cc_test {
         "FillBuffer.cpp",
         "GLTest.cpp",
         "IGraphicBufferProducer_test.cpp",
+        "Malicious.cpp",
         "MultiTextureConsumer_test.cpp",
         "StreamSplitter_test.cpp",
         "SurfaceTextureClient_test.cpp",

diff --git a/libs/gui/tests/Malicious.cpp b/libs/gui/tests/Malicious.cpp
new file mode 100644 (file)
index 0000000..7ecf08c
--- /dev/null
+++ b/libs/gui/tests/Malicious.cpp
@@ -0,0 +1,202 @@
+/*
+ * Copyright 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 <gui/BufferQueue.h>
+#include <gui/IProducerListener.h>
+#include <gui/Surface.h>
+
+#include <android/native_window.h>
+
+#include <gtest/gtest.h>
+
+namespace android {
+namespace test {
+
+class ProxyBQP : public BnGraphicBufferProducer {
+public:
+    ProxyBQP(const sp<IGraphicBufferProducer>& producer) : mProducer(producer) {}
+
+    // Pass through calls to mProducer
+    status_t requestBuffer(int slot, sp<GraphicBuffer>* buf) override {
+        return mProducer->requestBuffer(slot, buf);
+    }
+    status_t setMaxDequeuedBufferCount(int maxDequeuedBuffers) override {
+        return mProducer->setMaxDequeuedBufferCount(maxDequeuedBuffers);
+    }
+    status_t setAsyncMode(bool async) override { return mProducer->setAsyncMode(async); }
+    status_t dequeueBuffer(int* slot, sp<Fence>* fence, uint32_t w, uint32_t h, PixelFormat format,
+                           uint32_t usage, FrameEventHistoryDelta* outTimestamps) override {
+        return mProducer->dequeueBuffer(slot, fence, w, h, format, usage, outTimestamps);
+    }
+    status_t detachBuffer(int slot) override { return mProducer->detachBuffer(slot); }
+    status_t detachNextBuffer(sp<GraphicBuffer>* outBuffer, sp<Fence>* outFence) override {
+        return mProducer->detachNextBuffer(outBuffer, outFence);
+    }
+    status_t attachBuffer(int* outSlot, const sp<GraphicBuffer>& buffer) override {
+        return mProducer->attachBuffer(outSlot, buffer);
+    }
+    status_t queueBuffer(int slot, const QueueBufferInput& input,
+                         QueueBufferOutput* output) override {
+        return mProducer->queueBuffer(slot, input, output);
+    }
+    status_t cancelBuffer(int slot, const sp<Fence>& fence) override {
+        return mProducer->cancelBuffer(slot, fence);
+    }
+    int query(int what, int* value) override { return mProducer->query(what, value); }
+    status_t connect(const sp<IProducerListener>& listener, int api, bool producerControlledByApp,
+                     QueueBufferOutput* output) override {
+        return mProducer->connect(listener, api, producerControlledByApp, output);
+    }
+    status_t disconnect(int api, DisconnectMode mode) override {
+        return mProducer->disconnect(api, mode);
+    }
+    status_t setSidebandStream(const sp<NativeHandle>& stream) override {
+        return mProducer->setSidebandStream(stream);
+    }
+    void allocateBuffers(uint32_t width, uint32_t height, PixelFormat format,
+                         uint32_t usage) override {
+        mProducer->allocateBuffers(width, height, format, usage);
+    }
+    status_t allowAllocation(bool allow) override { return mProducer->allowAllocation(allow); }
+    status_t setGenerationNumber(uint32_t generationNumber) override {
+        return mProducer->setGenerationNumber(generationNumber);
+    }
+    String8 getConsumerName() const override { return mProducer->getConsumerName(); }
+    status_t setSharedBufferMode(bool sharedBufferMode) override {
+        return mProducer->setSharedBufferMode(sharedBufferMode);
+    }
+    status_t setAutoRefresh(bool autoRefresh) override {
+        return mProducer->setAutoRefresh(autoRefresh);
+    }
+    status_t setDequeueTimeout(nsecs_t timeout) override {
+        return mProducer->setDequeueTimeout(timeout);
+    }
+    status_t getLastQueuedBuffer(sp<GraphicBuffer>* outBuffer, sp<Fence>* outFence,
+                                 float outTransformMatrix[16]) override {
+        return mProducer->getLastQueuedBuffer(outBuffer, outFence, outTransformMatrix);
+    }
+    void getFrameTimestamps(FrameEventHistoryDelta*) override {}
+    status_t getUniqueId(uint64_t* outId) const override { return mProducer->getUniqueId(outId); }
+
+protected:
+    sp<IGraphicBufferProducer> mProducer;
+};
+
+class MaliciousBQP : public ProxyBQP {
+public:
+    MaliciousBQP(const sp<IGraphicBufferProducer>& producer) : ProxyBQP(producer) {}
+
+    void beMalicious(int32_t value) { mMaliciousValue = value; }
+
+    void setExpectedSlot(int32_t slot) { mExpectedSlot = slot; }
+
+    // Override dequeueBuffer, optionally corrupting the returned slot number
+    status_t dequeueBuffer(int* buf, sp<Fence>* fence, uint32_t width, uint32_t height,
+                           PixelFormat format, uint32_t usage,
+                           FrameEventHistoryDelta* outTimestamps) override {
+        EXPECT_EQ(BUFFER_NEEDS_REALLOCATION,
+                  mProducer->dequeueBuffer(buf, fence, width, height, format, usage,
+                                           outTimestamps));
+        EXPECT_EQ(mExpectedSlot, *buf);
+        if (mMaliciousValue != 0) {
+            *buf = mMaliciousValue;
+            return NO_ERROR;
+        } else {
+            return BUFFER_NEEDS_REALLOCATION;
+        }
+    }
+
+private:
+    int32_t mMaliciousValue = 0;
+    int32_t mExpectedSlot = 0;
+};
+
+class DummyListener : public BnConsumerListener {
+public:
+    void onFrameAvailable(const BufferItem&) override {}
+    void onBuffersReleased() override {}
+    void onSidebandStreamChanged() override {}
+};
+
+sp<MaliciousBQP> getMaliciousBQP() {
+    sp<IGraphicBufferProducer> producer;
+    sp<IGraphicBufferConsumer> consumer;
+    BufferQueue::createBufferQueue(&producer, &consumer);
+    sp<IConsumerListener> listener = new DummyListener;
+    consumer->consumerConnect(listener, false);
+
+    sp<MaliciousBQP> malicious = new MaliciousBQP(producer);
+    return malicious;
+}
+
+TEST(Malicious, Bug36991414Max) {
+    sp<MaliciousBQP> malicious = getMaliciousBQP();
+    sp<Surface> surface = new Surface(malicious);
+
+    ASSERT_EQ(NO_ERROR, surface->connect(NATIVE_WINDOW_API_CPU, nullptr, false));
+    ANativeWindow_Buffer buffer;
+    ASSERT_EQ(NO_ERROR, surface->lock(&buffer, nullptr));
+    ASSERT_EQ(NO_ERROR, surface->unlockAndPost());
+
+    malicious->setExpectedSlot(1);
+    malicious->beMalicious(std::numeric_limits<int32_t>::max());
+    ASSERT_EQ(FAILED_TRANSACTION, surface->lock(&buffer, nullptr));
+}
+
+TEST(Malicious, Bug36991414Min) {
+    sp<MaliciousBQP> malicious = getMaliciousBQP();
+    sp<Surface> surface = new Surface(malicious);
+
+    ASSERT_EQ(NO_ERROR, surface->connect(NATIVE_WINDOW_API_CPU, nullptr, false));
+    ANativeWindow_Buffer buffer;
+    ASSERT_EQ(NO_ERROR, surface->lock(&buffer, nullptr));
+    ASSERT_EQ(NO_ERROR, surface->unlockAndPost());
+
+    malicious->setExpectedSlot(1);
+    malicious->beMalicious(std::numeric_limits<int32_t>::min());
+    ASSERT_EQ(FAILED_TRANSACTION, surface->lock(&buffer, nullptr));
+}
+
+TEST(Malicious, Bug36991414NegativeOne) {
+    sp<MaliciousBQP> malicious = getMaliciousBQP();
+    sp<Surface> surface = new Surface(malicious);
+
+    ASSERT_EQ(NO_ERROR, surface->connect(NATIVE_WINDOW_API_CPU, nullptr, false));
+    ANativeWindow_Buffer buffer;
+    ASSERT_EQ(NO_ERROR, surface->lock(&buffer, nullptr));
+    ASSERT_EQ(NO_ERROR, surface->unlockAndPost());
+
+    malicious->setExpectedSlot(1);
+    malicious->beMalicious(-1);
+    ASSERT_EQ(FAILED_TRANSACTION, surface->lock(&buffer, nullptr));
+}
+
+TEST(Malicious, Bug36991414NumSlots) {
+    sp<MaliciousBQP> malicious = getMaliciousBQP();
+    sp<Surface> surface = new Surface(malicious);
+
+    ASSERT_EQ(NO_ERROR, surface->connect(NATIVE_WINDOW_API_CPU, nullptr, false));
+    ANativeWindow_Buffer buffer;
+    ASSERT_EQ(NO_ERROR, surface->lock(&buffer, nullptr));
+    ASSERT_EQ(NO_ERROR, surface->unlockAndPost());
+
+    malicious->setExpectedSlot(1);
+    malicious->beMalicious(BufferQueueDefs::NUM_BUFFER_SLOTS);
+    ASSERT_EQ(FAILED_TRANSACTION, surface->lock(&buffer, nullptr));
+}
+
+} // namespace test
+} // namespace android