Timeout error found in cJSON_Compare

[Yunlongs]

Dear developers,

I found a timeout error in the cJSON_Compare API when fuzzing the cJSON library.

The following is the minimized POC code:

#include <fuzzer/FuzzedDataProvider.h>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include "cjson/cJSON.h"

int main() {
    bool case_sensitive_operations = true;
    bool recurse_duplicate = true;
    uint8_t operation_selector = 5;
    
    // Consume variable-size data for JSON strings and object keys
    std::string initial_json = "{\t\"%q\":{\t\"ky\"\001:{\"e\"\t:{\"ey\"\001:{\"\377\377\":{\"e\":{\"\037\"\001:{\"e\":{\"k\"\001:{\"e\"\t:{\t\"\"\001:{\"\377\377\"\001:{\"y\"\001:{\"seye\"\t:{\t\"ke\"\001:{\"\377k\"\001:{\"ke8\"\001:{\t\"%v\"\t:{\t\"key\"\001:{\"\377\377\377\037\"\001:{\"e\"\t:{\t\"k\"\001:{\"e\"\t:{\t\"k\"\001:{\"\377\377\377\"\001:{\"y\"\t:{\t\"ey\"\001:{\"\377\377\377\037\"\001:{\"e\"\t:{\"k\"\001:{\"e\"\t:{\t\"k\":{}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}}{\".t\000\000\000\377\377\377}";
    
    // Create initial JSON object using cJSON_Parse
    cJSON* root = nullptr;
    if (!initial_json.empty()) {
        root = cJSON_Parse(initial_json.c_str());
    }
    
    // Create a duplicate of the object using cJSON_Duplicate
    cJSON* duplicated_object = cJSON_Duplicate(root, recurse_duplicate ? 1 : 0);
    
    // Compare the original and duplicate objects using cJSON_Compare
    if (duplicated_object != nullptr) {
        cJSON_bool comparison_result = cJSON_Compare(root, duplicated_object, case_sensitive_operations ? 1 : 0);
        (void)comparison_result; // Suppress unused variable warning
    }

cleanup:
    // Clean up all allocated memory
    if (root != nullptr) {
        cJSON_Delete(root);
    }
    if (duplicated_object != nullptr) {
        cJSON_Delete(duplicated_object);
    }
    
    return 0;
}