RDS stands for Reliable Datagram Sockets, a Linux kernel networking subsystem that provides ordered datagram delivery. It is used for specialized, high-performance communication inside the kernel networking stack, and it can support features such as zerocopy send paths that reduce data copying by pinning user pages.
RDS matters in cyber security because performance features often have complex cleanup logic. If a send fails or resources are released in the wrong order, the kernel can end up with inconsistent accounting or stale state. That kind of bug can become a local privilege escalation issue, letting an unprivileged user abuse a kernel path to gain higher rights. For defenders, the key questions are whether the RDS feature is present, loaded, and needed, and whether the kernel build includes the relevant fixes or backports. In practice, security teams treat RDS like any other optional kernel subsystem: inventory it, patch it, and minimize exposure on systems that do not require it.