Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 06 May 2020 17:32:34 -0700 (PDT)
Message-Id: <20200506.173234.92268086246049661.davem@davemloft.net>
To:     f.fainelli@gmail.com
Cc:     netdev@vger.kernel.org, allen.pais@oracle.com, andrew@lunn.ch,
        vivien.didelot@gmail.com, kuba@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net] net: dsa: Do not leave DSA master with NULL
 netdev_ops
From:   David Miller <davem@davemloft.net>
In-Reply-To: <20200504201806.27192-1-f.fainelli@gmail.com>
References: <20200504201806.27192-1-f.fainelli@gmail.com>
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Florian Fainelli <f.fainelli@gmail.com>
Date: Mon,  4 May 2020 13:18:06 -0700

> When ndo_get_phys_port_name() for the CPU port was added we introduced
> an early check for when the DSA master network device in
> dsa_master_ndo_setup() already implements ndo_get_phys_port_name(). When
> we perform the teardown operation in dsa_master_ndo_teardown() we would
> not be checking that cpu_dp->orig_ndo_ops was successfully allocated and
> non-NULL initialized.
> 
> With network device drivers such as virtio_net, this leads to a NPD as
> soon as the DSA switch hanging off of it gets torn down because we are
> now assigning the virtio_net device's netdev_ops a NULL pointer.
> 
> Fixes: da7b9e9b00d4 ("net: dsa: Add ndo_get_phys_port_name() for CPU port")
> Reported-by: Allen Pais <allen.pais@oracle.com>
> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Applied and queued up for -stable, thanks Florian.