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Date:   Sat, 20 Aug 2022 18:26:57 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Cc:     syzkaller@googlegroups.com, george.kennedy@oracle.com,
        vegard.nossum@oracle.com, john.p.donnelly@oracle.com,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Jozsef Kadlecsik <kadlec@netfilter.org>,
        Roopa Prabhu <roopa@nvidia.com>,
        Nikolay Aleksandrov <razor@blackwall.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
        bridge@lists.linux-foundation.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] netfilter: ebtables: fix a NULL pointer dereference in
 ebt_do_table()
Message-ID: <YwELUWJw1qTatIiI@strlen.de>
References: <20220820070331.48817-1-harshit.m.mogalapalli@oracle.com>
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Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> wrote:
> In ebt_do_table() function dereferencing 'private->hook_entry[hook]'
> can lead to NULL pointer dereference. So add a check to prevent that.

This looks incorrect, i.e. paperimg over the problem.

If hook_entry[hook] is NULL, how did this make it to the eval loop?

I guess ebtables lacks a sanity check on incoming ruleset?