Merge #18565: tests: Add fuzzing harnesses for classes/functions in policy/fees.h, checkqueue.h and cuckoocache.h. Add fuzzing coverage.

283bd72156959f420f13acc7a34e513ca3446025 tests: Add coverage of {,Incremental}DynamicUsage(const std::set<X, Y>& s) to existing fuzzer (practicalswift)
bf76000493082da05bf7258a5038e16fa76cd143 tests: Add fuzzing harness for classes/functions in cuckoocache.h (practicalswift)
57890b2555ca347373109052f6789c23f46bc594 tests: Add fuzzing harness for classes/functions in checkqueue.h (practicalswift)
2df5701e902effa93834d9520690cbaca7e504f3 tests: Add coverage of GetVirtualTransactionSize(...) to existing fuzzer (practicalswift)
7b9a2dc86426926038b2f49d3d4ce4cb64dcd14b tests: Add fuzzing harness for AdditionOverflow(...) (practicalswift)
44fb2a596b4a1aa70253c4145c35be6de68da22a tests: Add fuzzing harness for FeeFilterRounder (practicalswift)

Pull request description:

  Includes:

  ```
  tests: Add fuzzing harness for FeeFilterRounder
  tests: Add fuzzing harness for classes/functions in checkqueue.h
  tests: Add fuzzing harness for classes/functions in cuckoocache.h
  tests: Add coverage of {,Incremental}DynamicUsage(const std::set<X, Y>& s) to existing fuzzer
  tests: Add coverage of GetVirtualTransactionSize(...) to existing fuzzer
  tests: Add fuzzing harness for AdditionOverflow(...)
  ```

  See [`doc/fuzzing.md`](https://github.com/bitcoin/bitcoin/blob/master/doc/fuzzing.md) for information on how to fuzz Bitcoin Core.

ACKs for top commit:
  MarcoFalke:
    ACK 283bd72156959f420f13acc7a34e513ca3446025

Tree-SHA512: 2361edfb5c47741b22d9fb996836c5250c5a26bc5e956039ea6a0c55ba2d36c78f241d66f85bc02f5b85b9b83d5fde56a5c4702b9d1b7ac4a9a3ae391ca79eaa

1 files changed, 65 insertions, 0 deletions

diff --git a/src/test/fuzz/checkqueue.cpp b/src/test/fuzz/checkqueue.cpp
new file mode 100644
index 0000000000..2ed097b827
--- /dev/null
+++ b/src/test/fuzz/checkqueue.cpp
@@ -0,0 +1,65 @@
+// Copyright (c) 2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <checkqueue.h>
+#include <optional.h>
+#include <test/fuzz/FuzzedDataProvider.h>
+#include <test/fuzz/fuzz.h>
+#include <test/fuzz/util.h>
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+namespace {
+struct DumbCheck {
+    const bool result = false;
+
+    DumbCheck() = default;
+
+    explicit DumbCheck(const bool _result) : result(_result)
+    {
+    }
+
+    bool operator()() const
+    {
+        return result;
+    }
+
+    void swap(DumbCheck& x)
+    {
+    }
+};
+} // namespace
+
+void test_one_input(const std::vector<uint8_t>& buffer)
+{
+    FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
+
+    const unsigned int batch_size = fuzzed_data_provider.ConsumeIntegralInRange<unsigned int>(0, 1024);
+    CCheckQueue<DumbCheck> check_queue_1{batch_size};
+    CCheckQueue<DumbCheck> check_queue_2{batch_size};
+    std::vector<DumbCheck> checks_1;
+    std::vector<DumbCheck> checks_2;
+    const int size = fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 1024);
+    for (int i = 0; i < size; ++i) {
+        const bool result = fuzzed_data_provider.ConsumeBool();
+        checks_1.emplace_back(result);
+        checks_2.emplace_back(result);
+    }
+    if (fuzzed_data_provider.ConsumeBool()) {
+        check_queue_1.Add(checks_1);
+    }
+    if (fuzzed_data_provider.ConsumeBool()) {
+        (void)check_queue_1.Wait();
+    }
+
+    CCheckQueueControl<DumbCheck> check_queue_control{&check_queue_2};
+    if (fuzzed_data_provider.ConsumeBool()) {
+        check_queue_control.Add(checks_2);
+    }
+    if (fuzzed_data_provider.ConsumeBool()) {
+        (void)check_queue_control.Wait();
+    }
+}