4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sabrina Dubroca <sd@xxxxxxxxxxxxxxx> [ Upstream commit 1cc5954f44150bb70cac07c3cc5df7cf0dfb61ec ] 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 <sd@xxxxxxxxxxxxxxx> Reviewed-by: Xin Long <lucien.xin@xxxxxxxxx> Acked-by: William Tu <u9012063@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/ip_gre.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -796,8 +796,14 @@ static void ipgre_link_update(struct net 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); } }