From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Graf <tgraf@suug.ch>
Subject: Re: [PATCH net-next 0/7] Allow to monitor multicast cache event via
 rtnetlink
Date: Tue, 11 Dec 2012 18:40:13 +0000
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Cc: David Miller <davem@davemloft.net>, David.Laight@ACULAB.COM,
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To: Nicolas Dichtel <nicolas.dichtel@6wind.com>
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On 12/11/12 at 04:03pm, Nicolas Dichtel wrote:
> In fact, it seems not so easy because most users of nlmsg_new() calculate
> the exact needed length, thus if we add an unpredicted attribute,
> the message will be too small.

True, we would either need to fix the calculations by accounting
for an additional 4 bytes for each 64bit arg or just reserve an
additional fixed amount for padding per message in nlmsg_new().