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Date:   Fri, 29 Sep 2023 13:30:43 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Phil Sutter <phil@nwl.cc>, Florian Westphal <fw@strlen.de>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        netfilter-devel@vger.kernel.org
Subject: Re: [nf PATCH v2 8/8] netfilter: nf_tables: Add locking for
 NFT_MSG_GETSETELEM_RESET requests
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Phil Sutter <phil@nwl.cc> wrote:
> On Thu, Sep 28, 2023 at 10:07:51PM +0200, Florian Westphal wrote:
> > I don't really like it though because misbehaving userspace
> > can lock out writers.
> 
> Make them inactive and free only after the dump is done? IIUC,
> nft_active_genmask() will return true again though after the second
> update, right?

Yes, however, in case of update and 'reset dump', we'll set the
NLM_F_DUMP_INTR flag, so userspace would restart the dump.

AFAIU, this means the original values of 'already-reset' counters
are lost given nft will restart the 'reset dump'.

Alternative is make nft not restart if reset-dump was requested,
but in that case the dump can be incomplete.