Re: [PATCH] net: geneve: modify IP header check in geneve6_xmit_skb

[Eric Dumazet <edumazet@google.com>]

On Thu, Apr 22, 2021 at 1:11 AM Phillip Potter <phil@philpotter.co.uk> wrote:
>
> Modify the check in geneve6_xmit_skb to use the size of a struct iphdr
> rather than struct ipv6hdr. This fixes two kernel selftest failures
> introduced by commit 6628ddfec758
> ("net: geneve: check skb is large enough for IPv4/IPv6 header"), without
> diminishing the fix provided by that commit.
>
> Reported-by: kernel test robot <oliver.sang@intel.com>
> Signed-off-by: Phillip Potter <phil@philpotter.co.uk>

SGTM, but _please_ add a Fixes: tag, since stable teams now depend on this,
more than human parsing the changelog.

Fixes: 6628ddfec758 ("net: geneve: check skb is large enough for
IPv4/IPv6 header")

> ---
>  drivers/net/geneve.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
> index 42f31c681846..a57a5e6f614f 100644
> --- a/drivers/net/geneve.c
> +++ b/drivers/net/geneve.c
> @@ -988,7 +988,7 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
>         __be16 sport;
>         int err;
>
> -       if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
> +       if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
>                 return -EINVAL;
>
>         sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
> --
> 2.30.2
>