This is a note to let you know that I've just added the patch titled ipvs: Fix checksumming on GSO of SCTP packets to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ipvs-fix-checksumming-on-gso-of-sctp-packets.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit be7c2be59337debd2f811c16b1f2111737129fcb Author: Ismael Luceno <iluceno@xxxxxxx> Date: Sun Apr 21 16:22:32 2024 +0200 ipvs: Fix checksumming on GSO of SCTP packets [ Upstream commit e10d3ba4d434ed172914617ed8d74bd411421193 ] It was observed in the wild that pairs of consecutive packets would leave the IPVS with the same wrong checksum, and the issue only went away when disabling GSO. IPVS needs to avoid computing the SCTP checksum when using GSO. Fixes: 90017accff61 ("sctp: Add GSO support") Co-developed-by: Firo Yang <firo.yang@xxxxxxxx> Signed-off-by: Ismael Luceno <iluceno@xxxxxxx> Tested-by: Andreas Taschner <andreas.taschner@xxxxxxxx> Acked-by: Julian Anastasov <ja@xxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c index b0cd7d08f2a7a..18e2e489d0e51 100644 --- a/net/netfilter/ipvs/ip_vs_proto_sctp.c +++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c @@ -123,7 +123,8 @@ sctp_snat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp, if (sctph->source != cp->vport || payload_csum || skb->ip_summed == CHECKSUM_PARTIAL) { sctph->source = cp->vport; - sctp_nat_csum(skb, sctph, sctphoff); + if (!skb_is_gso(skb) || !skb_is_gso_sctp(skb)) + sctp_nat_csum(skb, sctph, sctphoff); } else { skb->ip_summed = CHECKSUM_UNNECESSARY; } @@ -171,7 +172,8 @@ sctp_dnat_handler(struct sk_buff *skb, struct ip_vs_protocol *pp, (skb->ip_summed == CHECKSUM_PARTIAL && !(skb_dst(skb)->dev->features & NETIF_F_SCTP_CRC))) { sctph->dest = cp->dport; - sctp_nat_csum(skb, sctph, sctphoff); + if (!skb_is_gso(skb) || !skb_is_gso_sctp(skb)) + sctp_nat_csum(skb, sctph, sctphoff); } else if (skb->ip_summed != CHECKSUM_PARTIAL) { skb->ip_summed = CHECKSUM_UNNECESSARY; }