Is there any mechanism that limits the memory usage of processes via memfd(2)?
Without memfd(2), there are ulimits -- you can use RLIMIT_AS to limit the address space size, and the number of file descriptors a process can create to store data in pipe buffers is limited, and the amount of data that can be stored in files is limited by file system sizes (on tmpfs, with `-o -s1G', for instance). But with memfd(2) it looks like, despite these limits, a process can write arbitrarily much data into it, and have random access to read any of it back later in small chunks with pread(2). The process could voluntarily prevent the memfd from increasing with F_SEAL_WRITE, but that can't be imposed from the outside, if I understand correctly. So is there a way to limit the memory use of memfd? Maybe the memfd should contribute toward RLIMIT_AS somehow, or something like that?