Subject: [net-next PATCH v2 3/8] udp: Do not pass MSS as parameter to GSO segmentation

From: Alexander Duyck <[email-masked]>
Date: Fri, 04 May 2018 11:29:52 -0700

From: Alexander Duyck <[email-masked]>

There is no point in passing MSS as a parameter for for the GSO
segmentation call as it is already available via the shared info for the
skb itself.

Signed-off-by: Alexander Duyck <[email-masked]>
---

v2: New break-out patch based on one patch from earlier series

 include/net/udp.h      |    2 +-
 net/ipv4/udp_offload.c |    6 ++++--
 net/ipv6/udp_offload.c |    2 +-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/include/net/udp.h b/include/net/udp.h
index 05990746810e..8bd83b044ecd 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -176,7 +176,7 @@ struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb,
 
 struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
 				  netdev_features_t features,
-				  unsigned int mss, __sum16 check);
+				  __sum16 check);
 
 static inline struct udphdr *udp_gro_udphdr(struct sk_buff *skb)
 {
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 8303fff42940..f21b63adcbbc 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -189,14 +189,16 @@ struct sk_buff *skb_udp_tunnel_segment(struct sk_buff *skb,
 
 struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
 				  netdev_features_t features,
-				  unsigned int mss, __sum16 check)
+				  __sum16 check)
 {
 	struct sk_buff *seg, *segs = ERR_PTR(-EINVAL);
 	struct sock *sk = gso_skb->sk;
 	unsigned int sum_truesize = 0;
 	unsigned int hdrlen;
 	struct udphdr *uh;
+	unsigned int mss;
 
+	mss = skb_shinfo(gso_skb)->gso_size;
 	if (gso_skb->len <= sizeof(*uh) + mss)
 		goto out;
 
@@ -247,7 +249,7 @@ static struct sk_buff *__udp4_gso_segment(struct sk_buff *gso_skb,
 	if (!can_checksum_protocol(features, htons(ETH_P_IP)))
 		return ERR_PTR(-EIO);
 
-	return __udp_gso_segment(gso_skb, features, mss,
+	return __udp_gso_segment(gso_skb, features,
 				 udp_v4_check(sizeof(struct udphdr) + mss,
 					      iph->saddr, iph->daddr, 0));
 }
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index f7b85b1e6b3e..dea03ec09715 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -26,7 +26,7 @@ static struct sk_buff *__udp6_gso_segment(struct sk_buff *gso_skb,
 	if (!can_checksum_protocol(features, htons(ETH_P_IPV6)))
 		return ERR_PTR(-EIO);
 
-	return __udp_gso_segment(gso_skb, features, mss,
+	return __udp_gso_segment(gso_skb, features,
 				 udp_v6_check(sizeof(struct udphdr) + mss,
 					      &ip6h->saddr, &ip6h->daddr, 0));
 }