While diving into BPF internals, I discovered certain types of attacks that can be used to mess with the internals of security solutions relying on BPF for prevention and detection. Specifically, an attacker could silently disable the delivery and execution of BPF programs, by stealing a file descriptor and completely
The goal of this post is to provide an in-depth discussion of BPF ring buffers, covering their internals, including memory allocation, user-space mapping, locking mechanisms, and efficient data sharing with user-land processes. This article is quite detailed, and I understand that some of you may not want to spend minutes
Writing performant, portable, and correct parallel programs in multiprocessor systems or SMP, where each processor may load and store to a single shared address space, is not trivial. Programmers must be aware of the underlying memory semantics, i.e. the system optimizations performed by the clever beast hardware or cpu.