The obvious solution is to block operations over io_uring if the equivalent syscall would have been blocked by seccomp. But I'm not sure if there is some reason that wouldn't work.
Another possibility would be to allow setting restrictions on all io_uring operations for the current and all child processes, although that would be less convenient than using the existing seccomp system.
Another possibility would be to allow setting restrictions on all io_uring operations for the current and all child processes, although that would be less convenient than using the existing seccomp system.