The virtual machine in the fine-grained information flow tracking is the basis for realization of transparent cloud platform program level control. The information flow control access to sensitive information in the process, because the authority transfer security level and cannot read or write the non sensitive data, the coarse granularity information flow control is difficult to meet the actual demand of diversification, this paper proposes extended DIFC (Distributed Information Flow Control) model, this model avoids component of cloud platform virtual machine because of the higher level of security sensitive data through reading, it sends or modifies the defects of non sensitive data by transfering the authority, and effectively overcomes the defect that the existing information flow control method for the coarse granularity, and the shortcomings which unable to meet the actual demand, this model guarantees the tracking and control of fine-grained information flow within the virtual machine application, and it does not affect the original cloud service operation.