[net PATCH 0/2] Fix outer UDP checksums for IPv6 VXLAN tunnels

[net PATCH 0/2] Fix outer UDP checksums for IPv6 VXLAN tunnels

[alexander.duyck]

In testing against an older kernel I found a couple issues in the IPv6
VXLAN tunnel checksum logic for the outer UDP checksum.

First the default transitioned from using an outer checksum to not using
one.  Second, sometime after that the checksum inputs were changed
resulting the checksum not being correct if it were computed.

These two issues prevented a ping from the newer kernel to the older one.
With these two changes applied I verified I was able to send traffic over
the VXLAN tunnel to a link partner on an older kernel.

The boolean flip fix can be submitted for 3.17 stable as well since the
patch that introduced the issue was included in that kernel.

---

Alexander Duyck (2):
      ip6_udp_tunnel: Fix checksum calculation
      vxlan: Fix boolean flip in VXLAN_F_UDP_ZERO_CSUM6_[TX|RX]


 drivers/net/vxlan.c       |    4 ++--
 net/ipv6/ip6_udp_tunnel.c |    4 +---
 2 files changed, 3 insertions(+), 5 deletions(-)

-- 

[net PATCH 1/2] ip6_udp_tunnel: Fix checksum calculation

[alexander.duyck]

From: Alexander Duyck <alexander.h.duyck@redhat.com>

The UDP checksum calculation for VXLAN tunnels is currently using the
socket addresses instead of the actual packet source and destination
addresses.  As a result the checksum calculated is incorrect in some
cases.

Also uh->check was being set twice, first it was set to 0, and then it is
set again in udp6_set_csum.  This change removes the redundant assignment
to 0.

Fixes: acbf74a7 ("vxlan: Refactor vxlan driver to make use of the common UDP tunnel functions.")

Cc: Andy Zhou <azhou@nicira.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
---
 net/ipv6/ip6_udp_tunnel.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/net/ipv6/ip6_udp_tunnel.c b/net/ipv6/ip6_udp_tunnel.c
index b04ed72..8db6c98 100644
--- a/net/ipv6/ip6_udp_tunnel.c
+++ b/net/ipv6/ip6_udp_tunnel.c
@@ -79,15 +79,13 @@ int udp_tunnel6_xmit_skb(struct socket *sock, struct dst_entry *dst,
 	uh->source = src_port;
 
 	uh->len = htons(skb->len);
-	uh->check = 0;
 
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED
 			    | IPSKB_REROUTED);
 	skb_dst_set(skb, dst);
 
-	udp6_set_csum(udp_get_no_check6_tx(sk), skb, &inet6_sk(sk)->saddr,
-		      &sk->sk_v6_daddr, skb->len);
+	udp6_set_csum(udp_get_no_check6_tx(sk), skb, saddr, daddr, skb->len);
 
 	__skb_push(skb, sizeof(*ip6h));
 	skb_reset_network_header(skb);

[net PATCH 2/2] vxlan: Fix boolean flip in VXLAN_F_UDP_ZERO_CSUM6_[TX|RX]

[alexander.duyck]

From: Alexander Duyck <alexander.h.duyck@redhat.com>

In "vxlan: Call udp_sock_create" there was a logic error that resulted in
the default for IPv6 VXLAN tunnels going from using checksums to not using
checksums.  Since there is currently no support in iproute2 for setting
these values it means that a kernel after the change cannot talk over a IPv6
VXLAN tunnel to a kernel prior the change.

Fixes: 3ee64f3 ("vxlan: Call udp_sock_create")

Cc: Tom Herbert <therbert@google.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
---
 drivers/net/vxlan.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index e1e335c..be4649a 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -2306,9 +2306,9 @@ static struct socket *vxlan_create_sock(struct net *net, bool ipv6,
 	if (ipv6) {
 		udp_conf.family = AF_INET6;
 		udp_conf.use_udp6_tx_checksums =
-		    !!(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
+		    !(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
 		udp_conf.use_udp6_rx_checksums =
-		    !!(flags & VXLAN_F_UDP_ZERO_CSUM6_RX);
+		    !(flags & VXLAN_F_UDP_ZERO_CSUM6_RX);
 	} else {
 		udp_conf.family = AF_INET;
 		udp_conf.local_ip.s_addr = INADDR_ANY;

Re: [net PATCH 2/2] vxlan: Fix boolean flip in VXLAN_F_UDP_ZERO_CSUM6_[TX|RX]

[Tom Herbert]

On Mon, Nov 24, 2014 at 8:08 PM,  <alexander.duyck@gmail.com> wrote:
> From: Alexander Duyck <alexander.h.duyck@redhat.com>
>
> In "vxlan: Call udp_sock_create" there was a logic error that resulted in
> the default for IPv6 VXLAN tunnels going from using checksums to not using
> checksums.  Since there is currently no support in iproute2 for setting
> these values it means that a kernel after the change cannot talk over a IPv6
> VXLAN tunnel to a kernel prior the change.
>
> Fixes: 3ee64f3 ("vxlan: Call udp_sock_create")
>
> Cc: Tom Herbert <therbert@google.com>
> Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
> ---
>  drivers/net/vxlan.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
> index e1e335c..be4649a 100644
> --- a/drivers/net/vxlan.c
> +++ b/drivers/net/vxlan.c
> @@ -2306,9 +2306,9 @@ static struct socket *vxlan_create_sock(struct net *net, bool ipv6,
>         if (ipv6) {
>                 udp_conf.family = AF_INET6;
>                 udp_conf.use_udp6_tx_checksums =
> -                   !!(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
> +                   !(flags & VXLAN_F_UDP_ZERO_CSUM6_TX);
>                 udp_conf.use_udp6_rx_checksums =
> -                   !!(flags & VXLAN_F_UDP_ZERO_CSUM6_RX);
> +                   !(flags & VXLAN_F_UDP_ZERO_CSUM6_RX);
>         } else {
>                 udp_conf.family = AF_INET;
>                 udp_conf.local_ip.s_addr = INADDR_ANY;
>

Acked-by: Tom Herbert <therbert@google.com>

Re: [net PATCH 0/2] Fix outer UDP checksums for IPv6 VXLAN tunnels

[David Miller]

From: alexander.duyck@gmail.com
Date: Mon, 24 Nov 2014 20:08:25 -0800

> In testing against an older kernel I found a couple issues in the IPv6
> VXLAN tunnel checksum logic for the outer UDP checksum.
> 
> First the default transitioned from using an outer checksum to not using
> one.  Second, sometime after that the checksum inputs were changed
> resulting the checksum not being correct if it were computed.
> 
> These two issues prevented a ping from the newer kernel to the older one.
> With these two changes applied I verified I was able to send traffic over
> the VXLAN tunnel to a link partner on an older kernel.
> 
> The boolean flip fix can be submitted for 3.17 stable as well since the
> patch that introduced the issue was included in that kernel.

Series applied and queued up for -stable, thanks.