Merged earlier this year for Linux 7.1 was extended attributes on sockets support as a feature sought after by the likes of GNOME and systemd for helping with Varlink IPC usage and other purposes.
A limitation though of the functionality has been no efficient means for a BPF program to read those user extended attribute labels back.
But with Linux 7.3 that's being addressed with the new bpf_sock_read_xattr() kernel function...