2017-09-03 12:49:55

by Haishuang Yan

Subject: [PATCH] geneve: Fix setting ttl value in collect metadata mode

If key->tos is zero in collect metadata mode, tos should fallback to
ip{4,6}_dst_hoplimit, same as normal mode.

Signed-off-by: Haishuang Yan <[email protected]>
---
drivers/net/geneve.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index f640407..d52a65f 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
if (geneve->collect_md) {
tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
- ttl = key->ttl;
} else {
tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb);
- ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst);
}
+ ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst);
df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;

err = geneve_build_skb(&rt->dst, skb, info, xnet, sizeof(struct iphdr));
@@ -873,12 +872,11 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
if (geneve->collect_md) {
prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
- ttl = key->ttl;
} else {
prio = ip_tunnel_ecn_encap(ip6_tclass(fl6.flowlabel),
ip_hdr(skb), skb);
- ttl = key->ttl ? : ip6_dst_hoplimit(dst);
}
+ ttl = key->ttl ? : ip6_dst_hoplimit(dst);
err = geneve_build_skb(dst, skb, info, xnet, sizeof(struct ipv6hdr));
if (unlikely(err))
return err;
--
1.8.3.1

2017-09-05 06:47:52

by Pravin Shelar

Subject: Re: [PATCH] geneve: Fix setting ttl value in collect metadata mode

On Sun, Sep 3, 2017 at 5:49 AM, Haishuang Yan
<[email protected]> wrote:
> If key->tos is zero in collect metadata mode, tos should fallback to
> ip{4,6}_dst_hoplimit, same as normal mode.
>
> Signed-off-by: Haishuang Yan <[email protected]>
> ---
> drivers/net/geneve.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
> index f640407..d52a65f 100644
> --- a/drivers/net/geneve.c
> +++ b/drivers/net/geneve.c
> @@ -834,11 +834,10 @@ static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
> sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
> if (geneve->collect_md) {
> tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
> - ttl = key->ttl;
> } else {
> tos = ip_tunnel_ecn_encap(fl4.flowi4_tos, ip_hdr(skb), skb);
> - ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst);
> }
> + ttl = key->ttl ? : ip4_dst_hoplimit(&rt->dst);
In collect md mode, geneve has to set TTL value from tunnel metadata.
That is the API exposed to userspace. is there reason for this change?


> df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
>
> err = geneve_build_skb(&rt->dst, skb, info, xnet, sizeof(struct iphdr));
> @@ -873,12 +872,11 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
> sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
> if (geneve->collect_md) {
> prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
> - ttl = key->ttl;
> } else {
> prio = ip_tunnel_ecn_encap(ip6_tclass(fl6.flowlabel),
> ip_hdr(skb), skb);
> - ttl = key->ttl ? : ip6_dst_hoplimit(dst);
> }
> + ttl = key->ttl ? : ip6_dst_hoplimit(dst);
> err = geneve_build_skb(dst, skb, info, xnet, sizeof(struct ipv6hdr));
> if (unlikely(err))
> return err;
> --
> 1.8.3.1
>
>
>