ipvs: allow transmit of GRO aggregated skbs

Attempt at allowing LVS to transmit skbs of greater than MTU length that
have been aggregated by GRO and can thus be deaggregated by GSO.

Cc: Julian Anastasov <ja@ssi.bg>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Simon Horman <horms@verge.net.au>
(cherry picked from commit 8f1b03a4c18e8f3f0801447b62330faa8ed3bb37)
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index 30b3189bd29c9aa982d2bf2e1a5ba9d7e0309cdd..dd7da3c291a9ce971dfb138c874447e9a2235466 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_xmit.c
+++ b/net/netfilter/ipvs/ip_vs_xmit.c
@@ -245,7 +245,8 @@ ip_vs_bypass_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF))) {
+       if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF)) &&
+           !skb_is_gso(skb)) {
                ip_rt_put(rt);
                icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -309,7 +310,7 @@ ip_vs_bypass_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if (skb->len > mtu) {
+       if (skb->len > mtu && !skb_is_gso(skb)) {
                dst_release(&rt->u.dst);
                icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -376,7 +377,7 @@ ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF))) {
+       if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF)) && !skb_is_gso(skb)) {
                ip_rt_put(rt);
                icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
                IP_VS_DBG_RL_PKT(0, pp, skb, 0, "ip_vs_nat_xmit(): frag needed for");
@@ -452,7 +453,7 @@ ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if (skb->len > mtu) {
+       if (skb->len > mtu && !skb_is_gso(skb)) {
                dst_release(&rt->u.dst);
                icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
                IP_VS_DBG_RL_PKT(0, pp, skb, 0,
@@ -561,8 +562,8 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        df |= (old_iph->frag_off & htons(IP_DF));
 
-       if ((old_iph->frag_off & htons(IP_DF))
-           && mtu < ntohs(old_iph->tot_len)) {
+       if ((old_iph->frag_off & htons(IP_DF) &&
+           mtu < ntohs(old_iph->tot_len) && !skb_is_gso(skb))) {
                icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
                ip_rt_put(rt);
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -671,7 +672,7 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
        if (skb_dst(skb))
                skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
 
-       if (mtu < ntohs(old_iph->payload_len) + sizeof(struct ipv6hdr)) {
+       if (mtu < ntohs(old_iph->payload_len) + sizeof(struct ipv6hdr) && !skb_is_gso(skb)) {
                icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
                dst_release(&rt->u.dst);
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -760,7 +761,7 @@ ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if ((iph->frag_off & htons(IP_DF)) && skb->len > mtu) {
+       if ((iph->frag_off & htons(IP_DF)) && skb->len > mtu && !skb_is_gso(skb)) {
                icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
                ip_rt_put(rt);
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -888,7 +889,7 @@ ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if ((skb->len > mtu) && (ip_hdr(skb)->frag_off & htons(IP_DF))) {
+       if ((skb->len > mtu) && (ip_hdr(skb)->frag_off & htons(IP_DF)) && !skb_is_gso(skb)) {
                ip_rt_put(rt);
                icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);
@@ -963,7 +964,7 @@ ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        /* MTU checking */
        mtu = dst_mtu(&rt->u.dst);
-       if (skb->len > mtu) {
+       if (skb->len > mtu && !skb_is_gso(skb)) {
                dst_release(&rt->u.dst);
                icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
                IP_VS_DBG_RL("%s(): frag needed\n", __func__);