1 files changed, 144 insertions, 0 deletions
diff --git a/libs/binder/tests/parcel_fuzzer/main.cpp b/libs/binder/tests/parcel_fuzzer/main.cpp
new file mode 100644
index 0000000000..a47b753497
--- /dev/null
+++ b/libs/binder/tests/parcel_fuzzer/main.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright (C) 2019 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.
+ */
+#define FUZZ_LOG_TAG "main"
+
+#include "binder.h"
+#include "binder_ndk.h"
+#include "hwbinder.h"
+#include "util.h"
+
+#include <iostream>
+
+#include <android-base/logging.h>
+#include <binder/RpcSession.h>
+#include <fuzzbinder/random_parcel.h>
+#include <fuzzer/FuzzedDataProvider.h>
+
+#include <cstdlib>
+#include <ctime>
+#include <sys/resource.h>
+#include <sys/time.h>
+
+using android::fillRandomParcel;
+using android::RpcSession;
+using android::sp;
+
+void fillRandomParcel(::android::hardware::Parcel* p, FuzzedDataProvider&& provider) {
+    // TODO: functionality to create random parcels for libhwbinder parcels
+    std::vector<uint8_t> input = provider.ConsumeRemainingBytes<uint8_t>();
+    p->setData(input.data(), input.size());
+}
+static void fillRandomParcel(NdkParcelAdapter* p, FuzzedDataProvider&& provider) {
+    // fill underlying parcel using functions to fill random libbinder parcel
+    fillRandomParcel(p->parcel(), std::move(provider));
+}
+
+template <typename P>
+void doFuzz(const char* backend, const std::vector<ParcelRead<P>>& reads,
+            FuzzedDataProvider&& provider) {
+    // Allow some majority of the bytes to be dedicated to telling us what to
+    // do. The fixed value added here represents that we want to test doing a
+    // lot of 'instructions' even on really short parcels.
+    size_t maxInstructions = 20 + (provider.remaining_bytes() * 2 / 3);
+    // but don't always use that many instructions. We want to allow the fuzzer
+    // to explore large parcels with few instructions if it wants to.
+    std::vector<uint8_t> instructions = provider.ConsumeBytes<uint8_t>(
+            provider.ConsumeIntegralInRange<size_t>(0, maxInstructions));
+
+    P p;
+    if constexpr (std::is_same_v<P, android::Parcel>) {
+        if (provider.ConsumeBool()) {
+            auto session = sp<RpcSession>::make();
+            CHECK(session->addNullDebuggingClient());
+            p.markForRpc(session);
+            fillRandomParcelData(&p, std::move(provider));
+        } else {
+            fillRandomParcel(&p, std::move(provider));
+        }
+    } else {
+        fillRandomParcel(&p, std::move(provider));
+    }
+
+    // since we are only using a byte to index
+    CHECK(reads.size() <= 255) << reads.size();
+
+    FUZZ_LOG() << "backend: " << backend;
+    FUZZ_LOG() << "input: " << hexString(p.data(), p.dataSize());
+    FUZZ_LOG() << "instructions: " << hexString(instructions);
+
+    for (size_t i = 0; i + 1 < instructions.size(); i += 2) {
+        uint8_t a = instructions[i];
+        uint8_t readIdx = a % reads.size();
+
+        uint8_t b = instructions[i + 1];
+
+        FUZZ_LOG() << "Instruction: " << (i / 2) + 1 << "/" << instructions.size() / 2
+                   << " cmd: " << static_cast<size_t>(a) << " (" << static_cast<size_t>(readIdx)
+                   << ") arg: " << static_cast<size_t>(b) << " size: " << p.dataSize()
+                   << " avail: " << p.dataAvail() << " pos: " << p.dataPosition()
+                   << " cap: " << p.dataCapacity();
+
+        reads[readIdx](p, b);
+    }
+}
+
+size_t getHardMemoryLimit() {
+    struct rlimit limit;
+    CHECK(0 == getrlimit(RLIMIT_AS, &limit)) << errno;
+    return limit.rlim_max;
+}
+
+void setMemoryLimit(size_t cur, size_t max) {
+    const struct rlimit kLimit = {
+       .rlim_cur = cur,
+       .rlim_max = max,
+    };
+    CHECK(0 == setrlimit(RLIMIT_AS, &kLimit)) << errno;
+}
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+    static constexpr size_t kMemLimit = 1 * 1024 * 1024;
+    size_t hardLimit = getHardMemoryLimit();
+    setMemoryLimit(std::min(kMemLimit, hardLimit), hardLimit);
+
+    if (size <= 1) return 0;  // no use
+
+    // avoid timeouts, see b/142617274, b/142473153
+    if (size > 50000) return 0;
+
+    FuzzedDataProvider provider = FuzzedDataProvider(data, size);
+
+    const std::function<void(FuzzedDataProvider &&)> fuzzBackend[3] = {
+            [](FuzzedDataProvider&& provider) {
+                doFuzz<::android::hardware::Parcel>("hwbinder", HWBINDER_PARCEL_READ_FUNCTIONS,
+                                                    std::move(provider));
+            },
+            [](FuzzedDataProvider&& provider) {
+                doFuzz<::android::Parcel>("binder", BINDER_PARCEL_READ_FUNCTIONS,
+                                          std::move(provider));
+            },
+            [](FuzzedDataProvider&& provider) {
+                doFuzz<NdkParcelAdapter>("binder_ndk", BINDER_NDK_PARCEL_READ_FUNCTIONS,
+                                         std::move(provider));
+            },
+    };
+
+    provider.PickValueInArray(fuzzBackend)(std::move(provider));
+
+    setMemoryLimit(hardLimit, hardLimit);
+
+    return 0;
+}