From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH net-next 1/3] ip: discard IPv4 datagrams with
 overlapping segments.
Date: Thu, 2 Aug 2018 15:54:46 -0700
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        <20180802224600.43070-2-posk@google.com>
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Cc: David Miller <davem@davemloft.net>, netdev@vger.kernel.org,
        Eric Dumazet <edumazet@google.com>,
        Florian Westphal <fw@strlen.de>
To: Peter Oskolkov <posk@google.com>
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On Thu,  2 Aug 2018 22:45:58 +0000
Peter Oskolkov <posk@google.com> wrote:

> diff --git a/include/uapi/linux/snmp.h b/include/uapi/linux/snmp.h
> index e5ebc83827ab..da1a144f1a51 100644
> --- a/include/uapi/linux/snmp.h
> +++ b/include/uapi/linux/snmp.h
> @@ -40,6 +40,7 @@ enum
>  	IPSTATS_MIB_REASMREQDS,			/* ReasmReqds */
>  	IPSTATS_MIB_REASMOKS,			/* ReasmOKs */
>  	IPSTATS_MIB_REASMFAILS,			/* ReasmFails */
> +	IPSTATS_MIB_REASM_OVERLAPS,		/* ReasmOverlaps */
>  	IPSTATS_MIB_FRAGOKS,			/* FragOKs */
>  	IPSTATS_MIB_FRAGFAILS,			/* FragFails */
>  	IPSTATS_MIB_FRAGCREATES,		/* FragCreates */

Inserting new entries in the middle of an enum means the numeric
values will change. Isn't this going to break userspace ABI?