Re: [PATCH] net: mac802154: Fix a condition in the receive path

From: Stefan Schmidt <stefan@datenfreihafen.org>
To: Miquel Raynal <miquel.raynal@bootlin.com>,
	Alexander Aring <alex.aring@gmail.com>,
	linux-wpan@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Eric Dumazet <edumazet@google.com>,
	netdev@vger.kernel.org, David Girault <david.girault@qorvo.com>,
	Romuald Despres <romuald.despres@qorvo.com>,
	Frederic Blain <frederic.blain@qorvo.com>,
	Nicolas Schodet <nico@ni.fr.eu.org>,
	Thomas Petazzoni <thomas.petazzoni@bootlin.com>,
	stable@vger.kernel.org
Subject: Re: [PATCH] net: mac802154: Fix a condition in the receive path
Date: Mon, 29 Aug 2022 10:52:52 +0200	[thread overview]
Message-ID: <57b7d918-1da1-f490-4882-5ed25ea17503@datenfreihafen.org> (raw)
In-Reply-To: <20220826142954.254853-1-miquel.raynal@bootlin.com>

Hello Miquel.

On 26.08.22 16:29, Miquel Raynal wrote:
> Upon reception, a packet must be categorized, either it's destination is
> the host, or it is another host. A packet with no destination addressing
> fields may be valid in two situations:
> - the packet has no source field: only ACKs are built like that, we
>    consider the host as the destination.
> - the packet has a valid source field: it is directed to the PAN
>    coordinator, as for know we don't have this information we consider we
>    are not the PAN coordinator.
> 
> There was likely a copy/paste error made during a previous cleanup
> because the if clause is now containing exactly the same condition as in
> the switch case, which can never be true. In the past the destination
> address was used in the switch and the source address was used in the
> if, which matches what the spec says.
> 
> Cc: stable@vger.kernel.org
> Fixes: ae531b9475f6 ("ieee802154: use ieee802154_addr instead of *_sa variants")
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>   net/mac802154/rx.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/mac802154/rx.c b/net/mac802154/rx.c
> index b8ce84618a55..c439125ef2b9 100644
> --- a/net/mac802154/rx.c
> +++ b/net/mac802154/rx.c
> @@ -44,7 +44,7 @@ ieee802154_subif_frame(struct ieee802154_sub_if_data *sdata,
>   
>   	switch (mac_cb(skb)->dest.mode) {
>   	case IEEE802154_ADDR_NONE:
> -		if (mac_cb(skb)->dest.mode != IEEE802154_ADDR_NONE)
> +		if (hdr->source.mode != IEEE802154_ADDR_NONE)
>   			/* FIXME: check if we are PAN coordinator */
>   			skb->pkt_type = PACKET_OTHERHOST;
>   		else

This patch has been applied to the wpan tree and will be
part of the next pull request to net. Thanks!

regards
Stefan Schmidt