On 1/28/2020 1:35 PM, Stefan Metzmacher wrote: > Hi Pavel, > >>> That's good in order to make the behavior consistent again and prevents >>> potential random security problems. >> >> BTW, there also can be problems with registered resources. E.g. for >> buffers io_uring can get_user_pages() of one process, and then use the >> pages from another process by passing a buffer index. This is not as >> bad, however. > > Yes, but that can only happen by intention, right? > And not randomly depending on the cache state. If the > application has confidential data in the registered buffers, files > then it should not share the ring fd with untrusted processes. Indeed, that's why it's a mild problem. Though, that's better to be said explicitly, so users know the pitfall. Worth putting into the manual, I think. -- Pavel Begunkov
