fuzz: Avoid -fsanitize=integer warnings in fuzzing harnesses

Author: practicalswift

src/test/fuzz/crypto_chacha20_poly1305_aead.cpp

@@ -45,18 +45,24 @@ FUZZ_TARGET(crypto_chacha20_poly1305_aead)
                 assert(ok);
             },
             [&] {
+                if (AdditionOverflow(seqnr_payload, static_cast<uint64_t>(1))) {
+                    return;
+                }
                 seqnr_payload += 1;
                 aad_pos += CHACHA20_POLY1305_AEAD_AAD_LEN;
                 if (aad_pos + CHACHA20_POLY1305_AEAD_AAD_LEN > CHACHA20_ROUND_OUTPUT) {
                     aad_pos = 0;
+                    if (AdditionOverflow(seqnr_aad, static_cast<uint64_t>(1))) {
+                        return;
+                    }
                     seqnr_aad += 1;
                 }
             },
             [&] {
-                seqnr_payload = fuzzed_data_provider.ConsumeIntegral<int>();
+                seqnr_payload = fuzzed_data_provider.ConsumeIntegral<uint64_t>();
             },
             [&] {
-                seqnr_aad = fuzzed_data_provider.ConsumeIntegral<int>();
+                seqnr_aad = fuzzed_data_provider.ConsumeIntegral<uint64_t>();
             },
             [&] {
                 is_encrypt = fuzzed_data_provider.ConsumeBool();

src/test/fuzz/pow.cpp

@@ -43,7 +43,10 @@ FUZZ_TARGET_INIT(pow, initialize_pow)
                 current_block.nHeight = current_height;
             }
             if (fuzzed_data_provider.ConsumeBool()) {
-                current_block.nTime = fixed_time + current_height * consensus_params.nPowTargetSpacing;
+                const uint32_t seconds = current_height * consensus_params.nPowTargetSpacing;
+                if (!AdditionOverflow(fixed_time, seconds)) {
+                    current_block.nTime = fixed_time + seconds;
+                }
             }
             if (fuzzed_data_provider.ConsumeBool()) {
                 current_block.nBits = fixed_bits;

src/test/fuzz/script.cpp

@@ -154,13 +154,13 @@ FUZZ_TARGET_INIT(script, initialize_script)
 
     {
         WitnessUnknown witness_unknown_1{};
-        witness_unknown_1.version = fuzzed_data_provider.ConsumeIntegral<int>();
+        witness_unknown_1.version = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
         const std::vector<uint8_t> witness_unknown_program_1 = fuzzed_data_provider.ConsumeBytes<uint8_t>(40);
         witness_unknown_1.length = witness_unknown_program_1.size();
         std::copy(witness_unknown_program_1.begin(), witness_unknown_program_1.end(), witness_unknown_1.program);
 
         WitnessUnknown witness_unknown_2{};
-        witness_unknown_2.version = fuzzed_data_provider.ConsumeIntegral<int>();
+        witness_unknown_2.version = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
         const std::vector<uint8_t> witness_unknown_program_2 = fuzzed_data_provider.ConsumeBytes<uint8_t>(40);
         witness_unknown_2.length = witness_unknown_program_2.size();
         std::copy(witness_unknown_program_2.begin(), witness_unknown_program_2.end(), witness_unknown_2.program);

src/test/fuzz/util.h

@@ -196,7 +196,7 @@ template <typename WeakEnumType, size_t size>
         },
         [&] {
             WitnessUnknown witness_unknown{};
-            witness_unknown.version = fuzzed_data_provider.ConsumeIntegral<int>();
+            witness_unknown.version = fuzzed_data_provider.ConsumeIntegral<uint32_t>();
             const std::vector<uint8_t> witness_unknown_program_1 = fuzzed_data_provider.ConsumeBytes<uint8_t>(40);
             witness_unknown.length = witness_unknown_program_1.size();
             std::copy(witness_unknown_program_1.begin(), witness_unknown_program_1.end(), witness_unknown.program);