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Message-ID: <f687fe6f-3330-a9c5-4760-f753638c7b03@mcst.ru>
Date:   Wed, 21 Jun 2023 13:49:28 +0300
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From:   "Igor A. Artemiev" <Igor.A.Artemiev@mcst.ru>
Subject: Re: [lvc-project] [PATCH] netfilter: ebtables: remove unnecessary
 NULL check
To:     Florian Westphal <fw@strlen.de>
Cc:     Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        "David S . Miller" <davem@davemloft.net>,
        Paolo Abeni <pabeni@redhat.com>,
        Jakub Kicinski <kuba@kernel.org>,
        netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        lvc-project@linuxtesting.org
References: <20230620152549.2109063-1-Igor.A.Artemiev@mcst.ru>
 <20230620163806.GB3799@breakpoint.cc>
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On 6/20/23 19:38, Florian Westphal wrote:
> Igor Artemiev <Igor.A.Artemiev@mcst.ru> wrote:
>> In ebt_do_table() 'private->chainstack' cannot be NULL
>> and the 'cs' pointer is dereferenced below, so it does not make
>> sense to compare 'private->chainstack' with NULL.
> ?  Why do you think that?
>
The 'cs' pointer is dereferenced below without checking, as it is 
assumed to always be initialized with 
'private->chainstack[smp_processor_id()]'.
>> +	cs = private->chainstack[smp_processor_id()];
> Looks like NULL deref to me.  Did you test this?
>
No, I didn't test this.

Thanks,
Igor