Cross-program map writes via iterator check bypass

Authorization bypass in the Linux kernel allows local users to write data in another BPF program's exclusive map through an iterator. bpf_iter_attach_map binds a bpf_map_elem iterator directly to its target map, bypassing check_map_prog_compatibility, and exposes each value as writable. Reaching the path requires high local privileges and an exclusive map; the bounded consequence is cross-program map data disclosure and modification.