From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 1/1] netfilter: nf_ct_tcp: pack nf_ct_tcp_flags to
 match user space
Date: Tue, 09 Mar 2010 09:41:16 -0800 (PST)
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From: Jan Engelhardt <jengelh@medozas.de>
Date: Tue, 9 Mar 2010 18:03:02 +0100 (CET)

> On Tuesday 2010-03-09 17:48, Lutz Jaenicke wrote:
> 
>>On some platforms (here: Intel IXP4xx ARM big endian)
>>sizeof(struct nf_ct_tcp_flags) evaluates to 4 bytes while in the user
>>space code 2 bytes is hard coded.
> 
> Why does it evaluate to 4 bytes? That seems to go against all good C 
> practice.

It's just what the ARM ABI does.

We have to do something similar in the IPV6 stack for
the same reason.

struct nd_opt_hdr {
	__u8		nd_opt_type;
	__u8		nd_opt_len;
} __attribute__((__packed__));