From c194cf93c164ed1c71142485ee0f70f9f2d1fe35 Mon Sep 17 00:00:00 2001
From: Alexander Duyck <aduyck@mirantis.com>
Date: Wed, 9 Mar 2016 09:24:23 -0800
Subject: gro: Defer clearing of flush bit in tunnel paths

This patch updates the GRO handlers for GRE, VXLAN, GENEVE, and FOU so that
we do not clear the flush bit until after we have called the next level GRO
handler.  Previously this was being cleared before parsing through the list
of frames, however this resulted in several paths where either the bit
needed to be reset but wasn't as in the case of FOU, or cases where it was
being set as in GENEVE.  By just deferring the clearing of the bit until
after the next level protocol has been parsed we can avoid any unnecessary
bit twiddling and avoid bugs.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 33185b9..192631a 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -463,8 +463,6 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 			goto out;
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -481,14 +479,13 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 
 	rcu_read_lock();
 	ptype = gro_find_receive_by_type(type);
-	if (!ptype) {
-		flush = 1;
+	if (!ptype)
 		goto out_unlock;
-	}
 
 	skb_gro_pull(skb, gh_len);
 	skb_gro_postpull_rcsum(skb, gh, gh_len);
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 8eda76f..800106a7 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -591,8 +591,6 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -606,6 +604,7 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 	}
 
 	pp = eth_gro_receive(head, skb);
+	flush = 0;
 
 out:
 	skb_gro_remcsum_cleanup(skb, &grc);
diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index 88dab0c..7804842 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -319,8 +319,6 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, hdrlen);
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct guehdr *guehdr2;
 
@@ -352,6 +350,7 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 		goto out_unlock;
 
 	pp = ops->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index 47f4c54..540866d 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -175,8 +175,6 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 					     null_compute_pseudo);
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct gre_base_hdr *greh2;
 
@@ -213,6 +211,7 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 	skb_gro_postpull_rcsum(skb, greh, grehlen);
 
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();
-- 
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