SIGSEGV，分段错误。仅在linux上，它适用于windows

Question

我已经坚持了好几个小时，由于某种原因，我只在 Linux 上遇到了分段错误错误。它只发生在长度为 17 个或更多字符的数据包中。我正在使用 Enet 库来发送数据包。任何人都可以帮助我，我不知道我在这里缺少什么......

这是gdb输出的截图 这是服务器端示例：

void GameServer::start()
{
if (!m_isRunning)
    m_isRunning = true;

ENetEvent  event;
//ENetPacket *packet;

while (m_isRunning)
{
    while (enet_host_service(server, &event, 1000) > 0)
    {
        switch (event.type)
        {
        case ENET_EVENT_TYPE_CONNECT:
            std::cout << "A new client connected from ";
            std::cout << event.peer->address.host << " ";
            std::cout << event.peer->address.port << std::endl;

            break;
        case ENET_EVENT_TYPE_DISCONNECT:
            printf("%s disconnected.\n", event.peer->data);
            delete (char*)event.peer->data;
            break;
        case ENET_EVENT_TYPE_RECEIVE:
        {
            std::cout << "A packet of length ";
            std::cout << event.packet->dataLength;
            std::cout << " containing ";
            std::cout << event.packet->data;
            std::cout << " was received from ";
            printf("%s", event.peer->data);
            std::cout << " on channel ";
            std::cout << event.channelID << std::endl;

            // Split the packet data, ex:   packettype:data:data
            std::vector<std::string> tokens;
            std::string data;
            std::istringstream split((const char *)event.packet->data);

            // Process the packet data
            while (std::getline(split, data, ':')) Line 89: Crash here
                tokens.push_back(data);

            if (tokens.size() > 1)
            {

                //pc = player connected so we will broadcast the name to all peers
                if (tokens[0] == "pc")
                {
                    if (tokens.size() == 2)
                    {
                        char* data = new char[tokens[1].length() + 1];
                        strcpy(data, tokens[1].c_str());
                        event.peer->data = (void*)data;
                        for (size_t i = 0; i < server->connectedPeers; i++)
                        {
                            enet_host_broadcast(server, 0, event.packet);
                        }
                    }
                }

                //ma = message all so we are going to broadcast the message to all peers
                else if (tokens[0] == "ma") 
                {
                    if (tokens.size() == 2)
                    {
                        enet_host_broadcast(server, 0, event.packet);
                    }
                }


                /* One could just use enet_host_service() instead. */
                enet_host_flush(server);
            }
            /* Clean up the packet now that we're done using it. */
            enet_packet_destroy(event.packet);
            break;
        }
        case ENET_EVENT_TYPE_NONE:
            break;
        default:
            break;
        }

    }
}

}

这是客户端创建数据包然后发送到服务器的方式。

if (connected) {
        std::cout << "Input: ";
        std::string str = "";
        std::getline(std::cin, str);

        if (str.length() == 0) { continue; }

        packet = enet_packet_create(str.c_str(), str.length() + 1, ENET_PACKET_FLAG_RELIABLE);
        enet_peer_send(peer, 0, packet);

    }

如果代码示例不够，我可以提供更多。

Answer 1

malloc() 中的崩溃通常意味着有人在某个时间更早写入了已分配缓冲区的末尾。该缓冲区溢出破坏了存储在空闲内存中以将空闲块链接在一起的指针。在malloc() 尝试使用这些指针之前，它没有引起问题。然后砰！

发布 event.packet 类型的声明。你确定 data[] 对于你放入的数据足够大吗？