diff options
Diffstat (limited to 'net/ipv4/ip_output.c')
| -rw-r--r-- | net/ipv4/ip_output.c | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 03e7f7310423..105908d841a3 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -239,19 +239,23 @@ static int ip_finish_output_gso(struct net *net, struct sock *sk, struct sk_buff *segs; int ret = 0; - /* common case: fragmentation of segments is not allowed, - * or seglen is <= mtu + /* common case: seglen is <= mtu */ - if (((IPCB(skb)->flags & IPSKB_FRAG_SEGS) == 0) || - skb_gso_validate_mtu(skb, mtu)) + if (skb_gso_validate_mtu(skb, mtu)) return ip_finish_output2(net, sk, skb); - /* Slowpath - GSO segment length is exceeding the dst MTU. + /* Slowpath - GSO segment length exceeds the egress MTU. * - * This can happen in two cases: - * 1) TCP GRO packet, DF bit not set - * 2) skb arrived via virtio-net, we thus get TSO/GSO skbs directly - * from host network stack. + * This can happen in several cases: + * - Forwarding of a TCP GRO skb, when DF flag is not set. + * - Forwarding of an skb that arrived on a virtualization interface + * (virtio-net/vhost/tap) with TSO/GSO size set by other network + * stack. + * - Local GSO skb transmitted on an NETIF_F_TSO tunnel stacked over an + * interface with a smaller MTU. + * - Arriving GRO skb (or GSO skb in a virtualized environment) that is + * bridged to a NETIF_F_TSO tunnel stacked over an interface with an + * insufficent MTU. */ features = netif_skb_features(skb); BUILD_BUG_ON(sizeof(*IPCB(skb)) > SKB_SGO_CB_OFFSET); @@ -1579,7 +1583,8 @@ void ip_send_unicast_reply(struct sock *sk, struct sk_buff *skb, } oif = arg->bound_dev_if; - oif = oif ? : skb->skb_iif; + if (!oif && netif_index_is_l3_master(net, skb->skb_iif)) + oif = skb->skb_iif; flowi4_init_output(&fl4, oif, IP4_REPLY_MARK(net, skb->mark), |