| Message ID | 20240425162842.23900-1-iluceno@suse.de (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v3] ipvs: Fix checksumming on GSO of SCTP packets | expand |
Hello, On Thu, 25 Apr 2024, Ismael Luceno wrote: > 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", 2016-06-02) > Co-developed-by: Firo Yang <firo.yang@suse.com> > Signed-off-by: Ismael Luceno <iluceno@suse.de> > Tested-by: Andreas Taschner <andreas.taschner@suse.com> > CC: Michal Kubeček <mkubecek@suse.com> > CC: Simon Horman <horms@verge.net.au> > CC: Julian Anastasov <ja@ssi.bg> > CC: lvs-devel@vger.kernel.org > CC: netfilter-devel@vger.kernel.org > CC: netdev@vger.kernel.org > CC: coreteam@netfilter.org > --- > > Notes: > Changes since v2: > * Use only skb_is_gso, no need to check for GSO type v2 is already applied. I acked it because sctp_gso_segment() checks for skb_is_gso_sctp(). If v3 is just an optimization better to live with v2? Is it possible to see skb_is_gso() but not skb_is_gso_sctp() while working with SCTP packet? > Changes since v1: > * Added skb_is_gso before skb_is_gso_sctp. > * Added "Fixes" tag. > > net/netfilter/ipvs/ip_vs_proto_sctp.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c > index a0921adc31a9..83e452916403 100644 > --- a/net/netfilter/ipvs/ip_vs_proto_sctp.c > +++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c > @@ -126,7 +126,8 @@ 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)) > + sctp_nat_csum(skb, sctph, sctphoff); > } else { > skb->ip_summed = CHECKSUM_UNNECESSARY; > } > @@ -174,7 +175,8 @@ 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)) > + sctp_nat_csum(skb, sctph, sctphoff); > } else if (skb->ip_summed != CHECKSUM_PARTIAL) { > skb->ip_summed = CHECKSUM_UNNECESSARY; > } > -- > 2.43.0 Regards -- Julian Anastasov <ja@ssi.bg>
On Thu, 25 Apr 2024 18:28:40 +0200 Ismael Luceno wrote: > Changes since v2: > * Use only skb_is_gso, no need to check for GSO type v2 is already in the tree, if the change is important you need to send an incremental fix.
Hi, On Thu, Apr 25, 2024 at 06:28:40PM +0200, Ismael Luceno wrote: > 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. This patch went already upstream. It was no clear to me that a v3 was needed. You will have to post a follow up.
diff --git a/net/netfilter/ipvs/ip_vs_proto_sctp.c b/net/netfilter/ipvs/ip_vs_proto_sctp.c index a0921adc31a9..83e452916403 100644 --- a/net/netfilter/ipvs/ip_vs_proto_sctp.c +++ b/net/netfilter/ipvs/ip_vs_proto_sctp.c @@ -126,7 +126,8 @@ 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)) + sctp_nat_csum(skb, sctph, sctphoff); } else { skb->ip_summed = CHECKSUM_UNNECESSARY; } @@ -174,7 +175,8 @@ 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)) + sctp_nat_csum(skb, sctph, sctphoff); } else if (skb->ip_summed != CHECKSUM_PARTIAL) { skb->ip_summed = CHECKSUM_UNNECESSARY; }
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", 2016-06-02) Co-developed-by: Firo Yang <firo.yang@suse.com> Signed-off-by: Ismael Luceno <iluceno@suse.de> Tested-by: Andreas Taschner <andreas.taschner@suse.com> CC: Michal Kubeček <mkubecek@suse.com> CC: Simon Horman <horms@verge.net.au> CC: Julian Anastasov <ja@ssi.bg> CC: lvs-devel@vger.kernel.org CC: netfilter-devel@vger.kernel.org CC: netdev@vger.kernel.org CC: coreteam@netfilter.org --- Notes: Changes since v2: * Use only skb_is_gso, no need to check for GSO type Changes since v1: * Added skb_is_gso before skb_is_gso_sctp. * Added "Fixes" tag. net/netfilter/ipvs/ip_vs_proto_sctp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)