Preventing unauthorized memory access using a physical address access permissions table

Abstract

A host may use address translation to convert virtual addresses to physical addresses for endpoints, which may then submit memory access requests for physical addresses. The host may record permissions granting entities access to physical addresses in physical address access permissions tables (PAAPTs) responsive to the address translation. The security of address translation services may be increased based at least on verifying memory access requests are authorized using the PAAPTs. For example, an entity identifier included in a request may be used to locate a corresponding PAAPT, and a physical address may be extracted from the request and used to locate an entry indicating whether an entity corresponding to the entity identifier has permission to access the physical address. Where the entity has permission, the system may perform the memory access using the physical address. Otherwise an error or fault code may be provided in response to the request.