On Tue, Apr 10, 2018 at 6:57 PM, Sabrina Dubroca <s...@queasysnail.net> wrote:
> Commit dd9d598c6657 ("ip_gre: add the support for i/o_flags update via
> netlink") added the ability to change o_flags, but missed that the
> GSO/LLTX features are disabled by default, and only enabled some gre
> features are unused. Thus we also need to disable the GSO/LLTX features
> on the device when the TUNNEL_SEQ or TUNNEL_CSUM flags are set.
>
> These two examples should result in the same features being set:
>
> ip link add gre_none type gre local 192.168.0.10 remote 192.168.0.20 ttl
> 255 key 0
>
> ip link set gre_none type gre seq
> ip link add gre_seq type gre local 192.168.0.10 remote 192.168.0.20 ttl
> 255 key 1 seq
>
> Fixes: dd9d598c6657 ("ip_gre: add the support for i/o_flags update via
> netlink")
> Signed-off-by: Sabrina Dubroca <s...@queasysnail.net>
> ---
> net/ipv4/ip_gre.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
> index a8772a978224..9c169bb2444d 100644
> --- a/net/ipv4/ip_gre.c
> +++ b/net/ipv4/ip_gre.c
> @@ -781,8 +781,14 @@ static void ipgre_link_update(struct net_device *dev,
> bool set_mtu)
> tunnel->encap.type == TUNNEL_ENCAP_NONE) {
> dev->features |= NETIF_F_GSO_SOFTWARE;
> dev->hw_features |= NETIF_F_GSO_SOFTWARE;
> + } else {
> + dev->features &= ~NETIF_F_GSO_SOFTWARE;
> + dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
> }
> dev->features |= NETIF_F_LLTX;
> + } else {
> + dev->hw_features &= ~NETIF_F_GSO_SOFTWARE;
> + dev->features &= ~(NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE);
> }
> }
>
> --
> 2.16.2
>
Reviewed-by: Xin Long <lucien....@gmail.com>
