Cloud storage auditing for shared data refers to the integrity auditing of cloud data shared by a group of users. Since users may join or leave user groups for various reasons, it usually supports user revocation. In most existing cloud storage auditing schemes for shared data, the computation cost of user revocation is linearly correlated to the number of file blocks to be uploaded by the user group, which results in high computation and communication costs. How to reduce the computation and communication overhead caused by user revocation has become a key issue for realizing shared cloud storage auditing. Therefore, this paper proposes an efficient and revocable cloud storage auditing scheme for shared data, which uses the elliptic curve technology to achieve unpaired authentication and the Chinese remainder theorem to attain efficient user revocation. On the basis of ensuring safe user revocation, this scheme greatly reduces communication and computation costs. In addition, it uses identity-based cryptography technology to solve the complex certificate management problem of traditional public key cryptography. The safety analysis and experimental results show that the proposed scheme is both feasible and efficient.