Programmable Blockchain brings a new type of decentralized applications (Dapps) that facilitate transfer of assets across users without a third party. The popularity of Ethereum Dapps brings themselves great security risks: they have been under various kinds of attacks from cybercriminals to gain profit. As the back-end of Dapps, smart contracts have been exploited their programming errors to steal cryptocurrency or tokens. Multiple approaches have been proposed to detect unsafe contracts. This paper presents a Blockchain Safe Browsing (BSB) platform to effectively disseminate smart contract detection results to contract users, and vulnerable contract owners. Based on those results, contract blacklist can be generated to provide user warning service, which is used to warn users before making transactions with unsafe contracts. Meanwhile, a contract owner notify mechanism is developed to help contract owners study the vulnerability details of their contract so that they can patch the vulnerabilities in time. Among the mechanism, the researchers will gain profits from shared data, which in turn inspire them keep uploading their research results. Moreover, as the most valuable asset for the researchers, vulnerability exploit details will be encrypted before uploading, and can only be decrypted by contract owners, which prevent the details being leaked and utilized by cybercriminals. Extensive evaluations using real datasets (with 2,880 unsafe contracts) demonstrate that our prototype can function as intended without sacrificing user experience, and warn users at the millisecond level.