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Message-ID: <68862d82fe886c8c7e3992bb9b892a14f6225bf7.camel@sipsolutions.net>
Subject: Re: [PATCH net] genetlink: reject use of nlmsg_flags for new
 commands
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Jakub Kicinski <kuba@kernel.org>, davem@davemloft.net
Cc:     netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com,
        Florent Fourcot <florent.fourcot@wifirst.fr>,
        Nikolay Aleksandrov <razor@blackwall.org>,
        Nicolas Dichtel <nicolas.dichtel@6wind.com>,
        Pablo Neira Ayuso <pablo@netfilter.org>,
        Florian Westphal <fw@strlen.de>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Jacob Keller <jacob.e.keller@intel.com>,
        Guillaume Nault <gnault@redhat.com>,
        Hangbin Liu <liuhangbin@gmail.com>
Date:   Wed, 28 Sep 2022 21:20:43 +0200
In-Reply-To: <20220928183515.1063481-1-kuba@kernel.org>
References: <20220928183515.1063481-1-kuba@kernel.org>
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On Wed, 2022-09-28 at 11:35 -0700, Jakub Kicinski wrote:
> Commit 9c5d03d36251 ("genetlink: start to validate reserved header bytes"=
)
> introduced extra validation for genetlink headers. We had to gate it
> to only apply to new commands, to maintain bug-wards compatibility.
> Use this opportunity (before the new checks make it to Linus's tree)
> to add more conditions.
>=20
> Validate that Generic Netlink families do not use nlmsg_flags outside
> of the well-understood set.

Makes sense.

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>

Thanks for doing this :)

johannes