From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pablo Neira Ayuso <pablo@netfilter.org>
Subject: Re: [nft PATCH v2 4/4] evaluate: Avoid undefined behaviour in
 concat_subtype_id()
Date: Mon, 5 Sep 2016 19:09:47 +0200
Message-ID: <20160905170947.GC17099@salvia>
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Cc: netfilter-devel@vger.kernel.org
To: Phil Sutter <phil@nwl.cc>
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On Tue, Aug 30, 2016 at 07:39:52PM +0200, Phil Sutter wrote:
> For the left side of a concat expression, dtype is NULL and therefore
> off is 0. In that case the code expects to get a datatype of
> TYPE_INVALID, but this is fragile as the output of concat_subtype_id()
> is undefined for n > 32 / TYPE_BITS.
> 
> To fix this, call datatype_lookup() directly passing the expected
> TYPE_INVALID as argument if off is 0.

Also applied, thanks!