diff --git a/src/test/fuzz/util.h b/src/test/fuzz/util.h
index d5c6e758f..068f9a7ae 100644
--- a/src/test/fuzz/util.h
+++ b/src/test/fuzz/util.h
@@ -1,490 +1,490 @@
 // Copyright (c) 2009-2019 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #ifndef BITCOIN_TEST_FUZZ_UTIL_H
 #define BITCOIN_TEST_FUZZ_UTIL_H
 
 #include <amount.h>
 #include <arith_uint256.h>
 #include <attributes.h>
 #include <chainparamsbase.h>
 #include <coins.h>
 #include <netbase.h>
 #include <script/script.h>
 #include <script/standard.h>
 #include <serialize.h>
 #include <streams.h>
 #include <uint256.h>
 #include <version.h>
 
 #include <test/fuzz/FuzzedDataProvider.h>
 #include <test/fuzz/fuzz.h>
 #include <test/util/setup_common.h>
 
 #include <algorithm>
 #include <cstdint>
 #include <cstdio>
 #include <string>
 #include <vector>
 
 namespace fuzzer {
 // FIXME find a better way to avoid duplicating the MAX_MONEY definition
 constexpr int64_t MAX_MONEY_AS_INT = int64_t(21000000) * int64_t(100000000);
 } // end namespace fuzzer
 
 using namespace fuzzer;
 
 NODISCARD inline std::vector<uint8_t>
 ConsumeRandomLengthByteVector(FuzzedDataProvider &fuzzed_data_provider,
                               const size_t max_length = 4096) noexcept {
     const std::string s =
         fuzzed_data_provider.ConsumeRandomLengthString(max_length);
     return {s.begin(), s.end()};
 }
 
 NODISCARD inline CDataStream
 ConsumeDataStream(FuzzedDataProvider &fuzzed_data_provider,
                   const size_t max_length = 4096) noexcept {
     return {ConsumeRandomLengthByteVector(fuzzed_data_provider, max_length),
             SER_NETWORK, INIT_PROTO_VERSION};
 }
 
 NODISCARD inline std::vector<std::string>
 ConsumeRandomLengthStringVector(FuzzedDataProvider &fuzzed_data_provider,
                                 const size_t max_vector_size = 16,
                                 const size_t max_string_length = 16) noexcept {
     const size_t n_elements =
         fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, max_vector_size);
     std::vector<std::string> r;
     for (size_t i = 0; i < n_elements; ++i) {
         r.push_back(
             fuzzed_data_provider.ConsumeRandomLengthString(max_string_length));
     }
     return r;
 }
 
 template <typename T>
 NODISCARD inline std::vector<T>
 ConsumeRandomLengthIntegralVector(FuzzedDataProvider &fuzzed_data_provider,
                                   const size_t max_vector_size = 16) noexcept {
     const size_t n_elements =
         fuzzed_data_provider.ConsumeIntegralInRange<size_t>(0, max_vector_size);
     std::vector<T> r;
     for (size_t i = 0; i < n_elements; ++i) {
         r.push_back(fuzzed_data_provider.ConsumeIntegral<T>());
     }
     return r;
 }
 
 template <typename T>
 NODISCARD inline std::optional<T>
 ConsumeDeserializable(FuzzedDataProvider &fuzzed_data_provider,
                       const size_t max_length = 4096) noexcept {
     const std::vector<uint8_t> buffer =
         ConsumeRandomLengthByteVector(fuzzed_data_provider, max_length);
     CDataStream ds{buffer, SER_NETWORK, INIT_PROTO_VERSION};
     T obj;
     try {
         ds >> obj;
     } catch (const std::ios_base::failure &) {
         return std::nullopt;
     }
     return obj;
 }
 
 NODISCARD inline opcodetype
 ConsumeOpcodeType(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return static_cast<opcodetype>(
         fuzzed_data_provider.ConsumeIntegralInRange<uint32_t>(0, MAX_OPCODE));
 }
 
 NODISCARD inline Amount
 ConsumeMoney(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return fuzzed_data_provider.ConsumeIntegralInRange<int64_t>(
                0, MAX_MONEY_AS_INT) *
            SATOSHI;
 }
 
 NODISCARD inline CScript
 ConsumeScript(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     const std::vector<uint8_t> b =
         ConsumeRandomLengthByteVector(fuzzed_data_provider);
     return {b.begin(), b.end()};
 }
 
 NODISCARD inline CScriptNum
 ConsumeScriptNum(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return CScriptNum{fuzzed_data_provider.ConsumeIntegral<int64_t>()};
 }
 
 NODISCARD inline uint160
 ConsumeUInt160(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     const std::vector<uint8_t> v160 =
         fuzzed_data_provider.ConsumeBytes<uint8_t>(160 / 8);
     if (v160.size() != 160 / 8) {
         return {};
     }
     return uint160{v160};
 }
 
 NODISCARD inline uint256
 ConsumeUInt256(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     const std::vector<uint8_t> v256 =
         fuzzed_data_provider.ConsumeBytes<uint8_t>(256 / 8);
     if (v256.size() != 256 / 8) {
         return {};
     }
     return uint256{v256};
 }
 
 NODISCARD inline arith_uint256
 ConsumeArithUInt256(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return UintToArith256(ConsumeUInt256(fuzzed_data_provider));
 }
 
 NODISCARD inline CTxDestination
 ConsumeTxDestination(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     CTxDestination tx_destination;
     switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 3)) {
         case 0: {
             tx_destination = CNoDestination{};
             break;
         }
         case 1: {
             tx_destination = PKHash{ConsumeUInt160(fuzzed_data_provider)};
             break;
         }
         case 2: {
             tx_destination = ScriptHash{ConsumeUInt160(fuzzed_data_provider)};
             break;
         }
     }
     return tx_destination;
 }
 
 template <typename T>
 NODISCARD bool MultiplicationOverflow(const T i, const T j) noexcept {
     static_assert(std::is_integral<T>::value, "Integral required.");
     if (std::numeric_limits<T>::is_signed) {
         if (i > 0) {
             if (j > 0) {
                 return i > (std::numeric_limits<T>::max() / j);
             } else {
                 return j < (std::numeric_limits<T>::min() / i);
             }
         } else {
             if (j > 0) {
                 return i < (std::numeric_limits<T>::min() / j);
             } else {
                 return i != 0 && (j < (std::numeric_limits<T>::max() / i));
             }
         }
     } else {
         return j != 0 && i > std::numeric_limits<T>::max() / j;
     }
 }
 
 template <class T>
 NODISCARD bool AdditionOverflow(const T i, const T j) noexcept {
     static_assert(std::is_integral<T>::value, "Integral required.");
     if (std::numeric_limits<T>::is_signed) {
         return (i > 0 && j > std::numeric_limits<T>::max() - i) ||
                (i < 0 && j < std::numeric_limits<T>::min() - i);
     }
     return std::numeric_limits<T>::max() - i < j;
 }
 
 NODISCARD inline bool
 ContainsSpentInput(const CTransaction &tx,
                    const CCoinsViewCache &inputs) noexcept {
     for (const CTxIn &tx_in : tx.vin) {
         const Coin &coin = inputs.AccessCoin(tx_in.prevout);
         if (coin.IsSpent()) {
             return true;
         }
     }
     return false;
 }
 
 /**
  * Returns a byte vector of specified size regardless of the number of remaining
  * bytes available from the fuzzer. Pads with zero value bytes if needed to
  * achieve the specified size.
  */
 NODISCARD inline std::vector<uint8_t>
 ConsumeFixedLengthByteVector(FuzzedDataProvider &fuzzed_data_provider,
                              const size_t length) noexcept {
     std::vector<uint8_t> result(length);
     const std::vector<uint8_t> random_bytes =
         fuzzed_data_provider.ConsumeBytes<uint8_t>(length);
     if (!random_bytes.empty()) {
         std::memcpy(result.data(), random_bytes.data(), random_bytes.size());
     }
     return result;
 }
 
 CNetAddr ConsumeNetAddr(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     const Network network = fuzzed_data_provider.PickValueInArray(
         {Network::NET_IPV4, Network::NET_IPV6, Network::NET_INTERNAL,
          Network::NET_ONION});
     CNetAddr net_addr;
     if (network == Network::NET_IPV4) {
         const in_addr v4_addr = {
             .s_addr = fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
         net_addr = CNetAddr{v4_addr};
     } else if (network == Network::NET_IPV6) {
         if (fuzzed_data_provider.remaining_bytes() >= 16) {
             in6_addr v6_addr = {};
             memcpy(v6_addr.s6_addr,
                    fuzzed_data_provider.ConsumeBytes<uint8_t>(16).data(), 16);
             net_addr = CNetAddr{
                 v6_addr, fuzzed_data_provider.ConsumeIntegral<uint32_t>()};
         }
     } else if (network == Network::NET_INTERNAL) {
         net_addr.SetInternal(fuzzed_data_provider.ConsumeBytesAsString(32));
     } else if (network == Network::NET_ONION) {
         net_addr.SetSpecial(fuzzed_data_provider.ConsumeBytesAsString(32));
     }
     return net_addr;
 }
 
 CSubNet ConsumeSubNet(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return {ConsumeNetAddr(fuzzed_data_provider),
             fuzzed_data_provider.ConsumeIntegral<int32_t>()};
 }
 
 void InitializeFuzzingContext(
     const std::string &chain_name = CBaseChainParams::REGTEST) {
     static const BasicTestingSetup basic_testing_setup{chain_name,
                                                        {"-nodebuglogfile"}};
 }
 
 class FuzzedFileProvider {
     FuzzedDataProvider &m_fuzzed_data_provider;
     int64_t m_offset = 0;
 
 public:
     FuzzedFileProvider(FuzzedDataProvider &fuzzed_data_provider)
         : m_fuzzed_data_provider{fuzzed_data_provider} {}
 
     FILE *open() {
         if (m_fuzzed_data_provider.ConsumeBool()) {
             return nullptr;
         }
         std::string mode;
         switch (m_fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 5)) {
             case 0: {
                 mode = "r";
                 break;
             }
             case 1: {
                 mode = "r+";
                 break;
             }
             case 2: {
                 mode = "w";
                 break;
             }
             case 3: {
                 mode = "w+";
                 break;
             }
             case 4: {
                 mode = "a";
                 break;
             }
             case 5: {
                 mode = "a+";
                 break;
             }
         }
 #ifdef _GNU_SOURCE
         const cookie_io_functions_t io_hooks = {
             FuzzedFileProvider::read,
             FuzzedFileProvider::write,
             FuzzedFileProvider::seek,
             FuzzedFileProvider::close,
         };
         return fopencookie(this, mode.c_str(), io_hooks);
 #else
         (void)mode;
         return nullptr;
 #endif
     }
 
     static ssize_t read(void *cookie, char *buf, size_t size) {
         FuzzedFileProvider *fuzzed_file = (FuzzedFileProvider *)cookie;
         if (buf == nullptr || size == 0 ||
             fuzzed_file->m_fuzzed_data_provider.ConsumeBool()) {
             return fuzzed_file->m_fuzzed_data_provider.ConsumeBool() ? 0 : -1;
         }
         const std::vector<uint8_t> random_bytes =
             fuzzed_file->m_fuzzed_data_provider.ConsumeBytes<uint8_t>(size);
         if (random_bytes.empty()) {
             return 0;
         }
         std::memcpy(buf, random_bytes.data(), random_bytes.size());
-        if (AdditionOverflow((uint64_t)fuzzed_file->m_offset,
-                             random_bytes.size())) {
+        if (AdditionOverflow(fuzzed_file->m_offset,
+                             int64_t(random_bytes.size()))) {
             return fuzzed_file->m_fuzzed_data_provider.ConsumeBool() ? 0 : -1;
         }
         fuzzed_file->m_offset += random_bytes.size();
         return random_bytes.size();
     }
 
     static ssize_t write(void *cookie, const char *buf, size_t size) {
         FuzzedFileProvider *fuzzed_file = (FuzzedFileProvider *)cookie;
         const ssize_t n =
             fuzzed_file->m_fuzzed_data_provider.ConsumeIntegralInRange<ssize_t>(
                 0, size);
-        if (AdditionOverflow(fuzzed_file->m_offset, n)) {
+        if (AdditionOverflow(fuzzed_file->m_offset, int64_t(n))) {
             return fuzzed_file->m_fuzzed_data_provider.ConsumeBool() ? 0 : -1;
         }
         fuzzed_file->m_offset += n;
         return n;
     }
 
     static int seek(void *cookie, int64_t *offset, int whence) {
         // SEEK_END not implemented yet.
         assert(whence == SEEK_SET || whence == SEEK_CUR);
         FuzzedFileProvider *fuzzed_file = (FuzzedFileProvider *)cookie;
         int64_t new_offset = 0;
         if (whence == SEEK_SET) {
             new_offset = *offset;
         } else if (whence == SEEK_CUR) {
             if (AdditionOverflow(fuzzed_file->m_offset, *offset)) {
                 return -1;
             }
             new_offset = fuzzed_file->m_offset + *offset;
         }
         if (new_offset < 0) {
             return -1;
         }
         fuzzed_file->m_offset = new_offset;
         *offset = new_offset;
         return fuzzed_file->m_fuzzed_data_provider.ConsumeIntegralInRange<int>(
             -1, 0);
     }
 
     static int close(void *cookie) {
         FuzzedFileProvider *fuzzed_file = (FuzzedFileProvider *)cookie;
         return fuzzed_file->m_fuzzed_data_provider.ConsumeIntegralInRange<int>(
             -1, 0);
     }
 };
 
 NODISCARD inline FuzzedFileProvider
 ConsumeFile(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return {fuzzed_data_provider};
 }
 
 class FuzzedAutoFileProvider {
     FuzzedDataProvider &m_fuzzed_data_provider;
     FuzzedFileProvider m_fuzzed_file_provider;
 
 public:
     FuzzedAutoFileProvider(FuzzedDataProvider &fuzzed_data_provider)
         : m_fuzzed_data_provider{fuzzed_data_provider},
           m_fuzzed_file_provider{fuzzed_data_provider} {}
 
     CAutoFile open() {
         return {m_fuzzed_file_provider.open(),
                 m_fuzzed_data_provider.ConsumeIntegral<int>(),
                 m_fuzzed_data_provider.ConsumeIntegral<int>()};
     }
 };
 
 NODISCARD inline FuzzedAutoFileProvider
 ConsumeAutoFile(FuzzedDataProvider &fuzzed_data_provider) noexcept {
     return {fuzzed_data_provider};
 }
 
 #define WRITE_TO_STREAM_CASE(id, type, consume)                                \
     case id: {                                                                 \
         type o = consume;                                                      \
         stream << o;                                                           \
         break;                                                                 \
     }
 template <typename Stream>
 void WriteToStream(FuzzedDataProvider &fuzzed_data_provider,
                    Stream &stream) noexcept {
     while (fuzzed_data_provider.ConsumeBool()) {
         try {
             switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 13)) {
                 WRITE_TO_STREAM_CASE(0, bool,
                                      fuzzed_data_provider.ConsumeBool())
                 WRITE_TO_STREAM_CASE(
                     1, char, fuzzed_data_provider.ConsumeIntegral<char>())
                 WRITE_TO_STREAM_CASE(
                     2, int8_t, fuzzed_data_provider.ConsumeIntegral<int8_t>())
                 WRITE_TO_STREAM_CASE(
                     3, uint8_t, fuzzed_data_provider.ConsumeIntegral<uint8_t>())
                 WRITE_TO_STREAM_CASE(
                     4, int16_t, fuzzed_data_provider.ConsumeIntegral<int16_t>())
                 WRITE_TO_STREAM_CASE(
                     5, uint16_t,
                     fuzzed_data_provider.ConsumeIntegral<uint16_t>())
                 WRITE_TO_STREAM_CASE(
                     6, int32_t, fuzzed_data_provider.ConsumeIntegral<int32_t>())
                 WRITE_TO_STREAM_CASE(
                     7, uint32_t,
                     fuzzed_data_provider.ConsumeIntegral<uint32_t>())
                 WRITE_TO_STREAM_CASE(
                     8, int64_t, fuzzed_data_provider.ConsumeIntegral<int64_t>())
                 WRITE_TO_STREAM_CASE(
                     9, uint64_t,
                     fuzzed_data_provider.ConsumeIntegral<uint64_t>())
                 WRITE_TO_STREAM_CASE(
                     10, float,
                     fuzzed_data_provider.ConsumeFloatingPoint<float>())
                 WRITE_TO_STREAM_CASE(
                     11, double,
                     fuzzed_data_provider.ConsumeFloatingPoint<double>())
                 WRITE_TO_STREAM_CASE(
                     12, std::string,
                     fuzzed_data_provider.ConsumeRandomLengthString(32))
                 WRITE_TO_STREAM_CASE(13, std::vector<char>,
                                      ConsumeRandomLengthIntegralVector<char>(
                                          fuzzed_data_provider))
             }
         } catch (const std::ios_base::failure &) {
             break;
         }
     }
 }
 
 #define READ_FROM_STREAM_CASE(id, type)                                        \
     case id: {                                                                 \
         type o;                                                                \
         stream >> o;                                                           \
         break;                                                                 \
     }
 template <typename Stream>
 void ReadFromStream(FuzzedDataProvider &fuzzed_data_provider,
                     Stream &stream) noexcept {
     while (fuzzed_data_provider.ConsumeBool()) {
         try {
             switch (fuzzed_data_provider.ConsumeIntegralInRange<int>(0, 13)) {
                 READ_FROM_STREAM_CASE(0, bool)
                 READ_FROM_STREAM_CASE(1, char)
                 READ_FROM_STREAM_CASE(2, int8_t)
                 READ_FROM_STREAM_CASE(3, uint8_t)
                 READ_FROM_STREAM_CASE(4, int16_t)
                 READ_FROM_STREAM_CASE(5, uint16_t)
                 READ_FROM_STREAM_CASE(6, int32_t)
                 READ_FROM_STREAM_CASE(7, uint32_t)
                 READ_FROM_STREAM_CASE(8, int64_t)
                 READ_FROM_STREAM_CASE(9, uint64_t)
                 READ_FROM_STREAM_CASE(10, float)
                 READ_FROM_STREAM_CASE(11, double)
                 READ_FROM_STREAM_CASE(12, std::string)
                 READ_FROM_STREAM_CASE(13, std::vector<char>)
             }
         } catch (const std::ios_base::failure &) {
             break;
         }
     }
 }
 
 #endif // BITCOIN_TEST_FUZZ_UTIL_H