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From:   Willem de Bruijn <willemb@google.com>
Date:   Thu, 12 Jan 2023 10:48:24 -0500
Message-ID: <CA+FuTSema7dvUzqh4rg2yX918svdQPEBY9mRMZKPK_Oi8E_Tmg@mail.gmail.com>
Subject: Re: [PATCH net 1/2] net/af_packet: fix tx skb protocol on SOCK_PACKET sockets
To:     =?UTF-8?Q?Herv=C3=A9_Boisse?= <admin@netgeek.ovh>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Tue, Jan 10, 2023 at 2:38 PM Herv=C3=A9 Boisse <admin@netgeek.ovh> wrote=
:
>
> Commit 75c65772c3d1 ("net/packet: Ask driver for protocol if not provided
> by user") introduces packet_parse_headers() to extract protocol for
> SOCK_RAW sockets.
> But, SOCK_PACKET sockets which provide similar behaviour are not consider=
ed
> so far and packets sent by those sockets will have their protocol unset.
>
> Extract the skb protocol value from the packet for SOCK_PACKET sockets, a=
s
> currently done for SOCK_RAW sockets.
>
> Fixes: 75c65772c3d1 ("net/packet: Ask driver for protocol if not provided=
 by user")
> Signed-off-by: Herv=C3=A9 Boisse <admin@netgeek.ovh>

Reviewed-by: Willem de Bruijn <willlemb@google.com>

packet_sendmsg_spkt (SOCK_PACKET) also prepares raw packets and
validates their link layer header length with dev_validate_header
before calling packet_parse_headers. It should be fine to call
dev_parse_protocol.

Technically this adds a feature to packets of type SOCK_PACKET.  I would
not qualify it as a bug fix. And not sure we care about adding new features=
 to
SOCK_PACKET. New applications should use SOCK_RAW.