From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 3/5] sctp: add spp_ipv6_flowlabel and spp_dscp
 for sctp_paddrparams
Date: Mon, 25 Jun 2018 16:31:26 +0900 (KST)
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From: Xin Long <lucien.xin@gmail.com>
Date: Mon, 25 Jun 2018 10:14:35 +0800

>  struct sctp_paddrparams {
> @@ -773,6 +775,8 @@ struct sctp_paddrparams {
>  	__u32			spp_pathmtu;
>  	__u32			spp_sackdelay;
>  	__u32			spp_flags;
> +	__u32			spp_ipv6_flowlabel;
> +	__u8			spp_dscp;
>  } __attribute__((packed, aligned(4)));

I don't think you can change the size of this structure like this.

This check in sctp_setsockopt_peer_addr_params():

	if (optlen != sizeof(struct sctp_paddrparams))
		return -EINVAL;

is going to trigger in old kernels when executing programs
built against the new struct definition.