netdev - Re: [PATCH net-next] net: virtio: use eth_hw_addr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 27 Oct 2021 03:23:17 -0400
From:   "Michael S. Tsirkin" <mst@...hat.com>
To:     Jakub Kicinski <kuba@...nel.org>
Cc:     davem@...emloft.net, netdev@...r.kernel.org, jasowang@...hat.com,
        virtualization@...ts.linux-foundation.org
Subject: Re: [PATCH net-next] net: virtio: use eth_hw_addr_set()

On Tue, Oct 26, 2021 at 10:56:34AM -0700, Jakub Kicinski wrote:
> Commit 406f42fa0d3c ("net-next: When a bond have a massive amount
> of VLANs...") introduced a rbtree for faster Ethernet address look
> up. To maintain netdev->dev_addr in this tree we need to make all
> the writes to it go through appropriate helpers.
> 
> Signed-off-by: Jakub Kicinski <kuba@...nel.org>

Acked-by: Michael S. Tsirkin <mst@...hat.com>

> ---
> CC: mst@...hat.com
> CC: jasowang@...hat.com
> CC: virtualization@...ts.linux-foundation.org
> ---
>  drivers/net/virtio_net.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index c501b5974aee..b7f35aff8e82 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -3177,12 +3177,16 @@ static int virtnet_probe(struct virtio_device *vdev)
>  	dev->max_mtu = MAX_MTU;
>  
>  	/* Configuration may specify what MAC to use.  Otherwise random. */
> -	if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC))
> +	if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
> +		u8 addr[MAX_ADDR_LEN];
> +
>  		virtio_cread_bytes(vdev,
>  				   offsetof(struct virtio_net_config, mac),
> -				   dev->dev_addr, dev->addr_len);
> -	else
> +				   addr, dev->addr_len);

Maybe BUG_ON(dev->addr_len > sizeof addr);

here just to make sure we don't overflow addr silently?


> +		dev_addr_set(dev, addr);
> +	} else {
>  		eth_hw_addr_random(dev);
> +	}
>  
>  	/* Set up our device-specific information */
>  	vi = netdev_priv(dev);
> -- 
> 2.31.1