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Date:   Wed, 21 Aug 2019 13:13:58 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Christian Ehrhardt <christian.ehrhardt@canonical.com>
Cc:     netfilter-devel@vger.kernel.org
Subject: Re: [RFC 1/1] nft: abort cache creation if mnl_genid_get fails
Message-ID: <20190821111358.GB13057@breakpoint.cc>
References: <20190821075611.30918-1-christian.ehrhardt@canonical.com>
 <20190821075611.30918-2-christian.ehrhardt@canonical.com>
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Christian Ehrhardt <christian.ehrhardt@canonical.com> wrote:
> mnl_genid_get can fail and in this case not update the genid which leads
> to a busy loop that never recovers.
> 
> To avoid that check the return value and abort __nft_build_cache
> if mnl_genid_get fails.

mnl_genid_get() aborts in case there is an error from mnl_talk in
iptables.git master branch.

See
commit e5cab728c40be88c541f68e4601d39178c36111f
nft: exit in case we can't fetch current genid

So I don't think this change is needed.

In the reported case this happened when calling iptables with
non-root user.