udpv4: Handle large incoming UDP/IPv4 packets and support software UFO.
- validate and forward GSO UDP/IPv4 packets from untrusted sources.
- do software UFO if the outgoing device doesn't support UFO.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 566ea6c..197d024 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1187,6 +1187,7 @@
int proto;
int ihl;
int id;
+ unsigned int offset = 0;
if (!(features & NETIF_F_V4_CSUM))
features &= ~NETIF_F_SG;
@@ -1229,7 +1230,14 @@
skb = segs;
do {
iph = ip_hdr(skb);
- iph->id = htons(id++);
+ if (proto == IPPROTO_UDP) {
+ iph->id = htons(id);
+ iph->frag_off = htons(offset >> 3);
+ if (skb->next != NULL)
+ iph->frag_off |= htons(IP_MF);
+ offset += (skb->len - skb->mac_len - iph->ihl * 4);
+ } else
+ iph->id = htons(id++);
iph->tot_len = htons(skb->len - skb->mac_len);
iph->check = 0;
iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
@@ -1425,6 +1433,8 @@
static struct net_protocol udp_protocol = {
.handler = udp_rcv,
.err_handler = udp_err,
+ .gso_send_check = udp4_ufo_send_check,
+ .gso_segment = udp4_ufo_fragment,
.no_policy = 1,
.netns_ok = 1,
};