Looks like changes to SCTP events create kernel ABI breakage in applications.

If application is compiled with new header but attempts to run on older kernel, it doesn't work:

Reported here: https://osmocom.org/issues/5366

Looks like bad design assumptions about how setsockopt here:
static int sctp_setsockopt_events(struct sock *sk, __u8 *sn_type,
				  unsigned int optlen)
{
	struct sctp_sock *sp = sctp_sk(sk);
	struct sctp_association *asoc;
	int i;

	if (optlen > sizeof(struct sctp_event_subscribe))
		return -EINVAL;

Because of that the commits that add new events cause code built with the new
header to not run on older kernels.