Commit 3189a290 authored Dec 05, 2016 by Davide Caratti Committed by Pablo Neira Ayuso Dec 07, 2016

netfilter: nat: skip checksum on offload SCTP packets

SCTP GSO and hardware can do CRC32c computation after netfilter processing,
so we can avoid calling sctp_compute_checksum() on skb if skb->ip_summed
is equal to CHECKSUM_PARTIAL. Moreover, set skb->ip_summed to CHECKSUM_NONE
when the NAT code computes the CRC, to prevent offloaders from computing
it again (on ixgbe this resulted in a transmission with wrong L4 checksum).

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

parent 3b760dcb

net/netfilter/nf_nat_proto_sctp.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -47,7 +47,10 @@ sctp_manip_pkt(struct sk_buff *skb,
		hdr->dest = tuple->dst.u.sctp.port;
		}

		if (skb->ip_summed != CHECKSUM_PARTIAL) {
		hdr->checksum = sctp_compute_cksum(skb, hdroff);
		skb->ip_summed = CHECKSUM_NONE;
		}

		return true;
		}