netdev - Re: [PATCH net] macvtap: fix network header pointer for VLAN tagged pkts

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:	Mon, 20 Jul 2015 12:42:42 -0400
From:	Vlad Yasevich <vyasevich@...il.com>
To:	Ivan Vecera <ivecera@...hat.com>, netdev@...r.kernel.org
Subject: Re: [PATCH net] macvtap: fix network header pointer for VLAN tagged
 pkts

On 07/20/2015 11:44 AM, Ivan Vecera wrote:
> Network header is set with offset ETH_HLEN but it is not true for VLAN
> (multiple-)tagged and results in checksum issues in lower devices.
> 
> Signed-off-by: Ivan Vecera <ivecera@...hat.com>
> ---
>  drivers/net/macvtap.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
> index 3b933bb..cdcbab4 100644
> --- a/drivers/net/macvtap.c
> +++ b/drivers/net/macvtap.c
> @@ -796,6 +796,12 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m,
>  	skb_reset_mac_header(skb);
>  	skb->protocol = eth_hdr(skb)->h_proto;
>  
> +	if (skb_vlan_tagged(skb)) {
> +		int depth;
> +		skb->protocol = __vlan_get_protocol(skb, skb->protocol, &depth);

I don't think this is right.  This would reset the protocol to the encapsulated
protocol which isn't really the case since you are not really stripping vlan
encapsulations.

-vlad

> +		skb_set_network_header(skb, depth);
> +	}
> +
>  	if (vnet_hdr_len) {
>  		err = macvtap_skb_from_vnet_hdr(q, skb, &vnet_hdr);
>  		if (err)
> 

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html