[PATCH net v3 1/2] udp_tunnel: Remove redundant udp_tunnel_gro_complete().

The setting of the UDP tunnel GSO type is already performed by
udp[46]_gro_complete().

Signed-off-by: Jarno Rajahalme <redacted>
---
 drivers/net/geneve.c     | 2 --
 drivers/net/vxlan.c      | 2 --
 include/net/udp_tunnel.h | 9 ---------
 net/ipv4/fou.c           | 2 --
 4 files changed, 15 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index bc16889..98f1224 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c

@@ -504,8 +504,6 @@ static int geneve_gro_complete(struct sk_buff *skb, int nhoff,
 	int gh_len;
 	int err = -ENOSYS;
 
-	udp_tunnel_gro_complete(skb, nhoff);
-
 	gh = (struct genevehdr *)(skb->data + nhoff);
 	gh_len = geneve_hlen(gh);
 	type = gh->proto_type;

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 1c0fa36..dd2d032 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c

@@ -616,8 +616,6 @@ out:
 static int vxlan_gro_complete(struct sk_buff *skb, int nhoff,
 			      struct udp_offload *uoff)
 {
-	udp_tunnel_gro_complete(skb, nhoff);
-
 	return eth_gro_complete(skb, nhoff + sizeof(struct vxlanhdr));
 }
 

diff --git a/include/net/udp_tunnel.h b/include/net/udp_tunnel.h
index b831140..a114024 100644
--- a/include/net/udp_tunnel.h
+++ b/include/net/udp_tunnel.h

@@ -106,15 +106,6 @@ static inline struct sk_buff *udp_tunnel_handle_offloads(struct sk_buff *skb,
 	return iptunnel_handle_offloads(skb, type);
 }
 
-static inline void udp_tunnel_gro_complete(struct sk_buff *skb, int nhoff)
-{
-	struct udphdr *uh;
-
-	uh = (struct udphdr *)(skb->data + nhoff - sizeof(struct udphdr));
-	skb_shinfo(skb)->gso_type |= uh->check ?
-				SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
-}
-
 static inline void udp_tunnel_encap_enable(struct socket *sock)
 {
 #if IS_ENABLED(CONFIG_IPV6)

diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index a39068b..305d9ac 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c

@@ -228,8 +228,6 @@ static int fou_gro_complete(struct sk_buff *skb, int nhoff,
 	int err = -ENOSYS;
 	const struct net_offload **offloads;
 
-	udp_tunnel_gro_complete(skb, nhoff);
-
 	rcu_read_lock();
 	offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
 	ops = rcu_dereference(offloads[proto]);

-- 
2.7.4

UDP tunnel segmentation code relies on the inner offsets being set for
an UDP tunnel GSO packet, but the inner *_complete() functions will
set the inner offsets only if 'encapsulation' is set before calling
them.  Currently, udp_gro_complete() sets 'encapsulation' only after
the inner *_complete() functions are done.  This causes the inner
offsets having invalid values after udp_gro_complete() returns, which
in turn will make it impossible to properly segment the packet in case
it needs to be forwarded, which would be visible to the user either as
invalid packets being sent or as packet loss.

This patch fixes this by setting skb's 'encapsulation' in
udp_gro_complete() before calling into the inner complete functions,
and by making each possible UDP tunnel gro_complete() callback set the
inner_mac_header to the beginning of the tunnel payload.

Signed-off-by: Jarno Rajahalme <redacted>
---
v3: Added setting inner_mac_header from all possible callbacks to cover
    cases where there is no inner mac header.

 drivers/net/geneve.c      | 3 +++
 drivers/net/vxlan.c       | 3 +++
 include/linux/netdevice.h | 3 +++
 net/ipv4/fou.c            | 4 ++++
 net/ipv4/udp_offload.c    | 8 +++++---
 5 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 98f1224..7b0a644 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c

@@ -514,6 +514,9 @@ static int geneve_gro_complete(struct sk_buff *skb, int nhoff,
 		err = ptype->callbacks.gro_complete(skb, nhoff + gh_len);
 
 	rcu_read_unlock();
+
+	skb_set_inner_mac_header(skb, nhoff + gh_len);
+
 	return err;
 }
 

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index dd2d032..8ac261a 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c

@@ -616,6 +616,9 @@ out:
 static int vxlan_gro_complete(struct sk_buff *skb, int nhoff,
 			      struct udp_offload *uoff)
 {
+	/* Sets 'skb->inner_mac_header' since we are always called with
+	 * 'skb->encapsulation' set.
+	 */
 	return eth_gro_complete(skb, nhoff + sizeof(struct vxlanhdr));
 }
 

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index b3c46b0..78181a8 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h

@@ -2164,6 +2164,9 @@ struct packet_offload {
 
 struct udp_offload;
 
+/* 'skb->encapsulation' is set before gro_complete() is called.  gro_complete()
+ * must set 'skb->inner_mac_header' to the beginning of tunnel payload.
+ */
 struct udp_offload_callbacks {
 	struct sk_buff		**(*gro_receive)(struct sk_buff **head,
 						 struct sk_buff *skb,

diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index 305d9ac..a6962cc 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c

@@ -236,6 +236,8 @@ static int fou_gro_complete(struct sk_buff *skb, int nhoff,
 
 	err = ops->callbacks.gro_complete(skb, nhoff);
 
+	skb_set_inner_mac_header(skb, nhoff);
+
 out_unlock:
 	rcu_read_unlock();
 

@@ -412,6 +414,8 @@ static int gue_gro_complete(struct sk_buff *skb, int nhoff,
 
 	err = ops->callbacks.gro_complete(skb, nhoff + guehlen);
 
+	skb_set_inner_mac_header(skb, nhoff + guehlen);
+
 out_unlock:
 	rcu_read_unlock();
 	return err;

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 0ed2daf..e330c0e 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c

@@ -399,6 +399,11 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff)
 
 	uh->len = newlen;
 
+	/* Set encapsulation before calling into inner gro_complete() functions
+	 * to make them set up the inner offsets.
+	 */
+	skb->encapsulation = 1;
+
 	rcu_read_lock();
 
 	uo_priv = rcu_dereference(udp_offload_base);

@@ -421,9 +426,6 @@ int udp_gro_complete(struct sk_buff *skb, int nhoff)
 	if (skb->remcsum_offload)
 		skb_shinfo(skb)->gso_type |= SKB_GSO_TUNNEL_REMCSUM;
 
-	skb->encapsulation = 1;
-	skb_set_inner_mac_header(skb, nhoff + sizeof(struct udphdr));
-
 	return err;
 }
 

-- 
2.7.4

From: Jarno Rajahalme <redacted>
Date: Tue,  3 May 2016 16:10:21 -0700

UDP tunnel segmentation code relies on the inner offsets being set for
an UDP tunnel GSO packet, but the inner *_complete() functions will
set the inner offsets only if 'encapsulation' is set before calling
them.  Currently, udp_gro_complete() sets 'encapsulation' only after
the inner *_complete() functions are done.  This causes the inner
offsets having invalid values after udp_gro_complete() returns, which
in turn will make it impossible to properly segment the packet in case
it needs to be forwarded, which would be visible to the user either as
invalid packets being sent or as packet loss.

This patch fixes this by setting skb's 'encapsulation' in
udp_gro_complete() before calling into the inner complete functions,
and by making each possible UDP tunnel gro_complete() callback set the
inner_mac_header to the beginning of the tunnel payload.

Signed-off-by: Jarno Rajahalme <redacted>
---
v3: Added setting inner_mac_header from all possible callbacks to cover
    cases where there is no inner mac header.

Alex and Tom, can you please review this new version since you guys had
so much feedback for v2?

THanks.

On Fri, May 6, 2016 at 12:34 PM, David Miller [off-list ref] wrote:

From: Jarno Rajahalme <redacted>
Date: Tue,  3 May 2016 16:10:21 -0700

quoted

UDP tunnel segmentation code relies on the inner offsets being set for
an UDP tunnel GSO packet, but the inner *_complete() functions will
set the inner offsets only if 'encapsulation' is set before calling
them.  Currently, udp_gro_complete() sets 'encapsulation' only after
the inner *_complete() functions are done.  This causes the inner
offsets having invalid values after udp_gro_complete() returns, which
in turn will make it impossible to properly segment the packet in case
it needs to be forwarded, which would be visible to the user either as
invalid packets being sent or as packet loss.

This patch fixes this by setting skb's 'encapsulation' in
udp_gro_complete() before calling into the inner complete functions,
and by making each possible UDP tunnel gro_complete() callback set the
inner_mac_header to the beginning of the tunnel payload.

Signed-off-by: Jarno Rajahalme <redacted>
---
v3: Added setting inner_mac_header from all possible callbacks to cover
    cases where there is no inner mac header.

Alex and Tom, can you please review this new version since you guys had
so much feedback for v2?

THanks.

I had reviewed it a day or so ago.  It did address the issues I saw
with the original patch, and from what I can tell it is fixing the
original issue reported.

Reviewed-by: Alexander Duyck <redacted>

On Fri, May 6, 2016 at 12:34 PM, David Miller [off-list ref] wrote:

From: Jarno Rajahalme <redacted>
Date: Tue,  3 May 2016 16:10:21 -0700

quoted

UDP tunnel segmentation code relies on the inner offsets being set for
an UDP tunnel GSO packet, but the inner *_complete() functions will
set the inner offsets only if 'encapsulation' is set before calling
them.  Currently, udp_gro_complete() sets 'encapsulation' only after
the inner *_complete() functions are done.  This causes the inner
offsets having invalid values after udp_gro_complete() returns, which
in turn will make it impossible to properly segment the packet in case
it needs to be forwarded, which would be visible to the user either as
invalid packets being sent or as packet loss.

This patch fixes this by setting skb's 'encapsulation' in
udp_gro_complete() before calling into the inner complete functions,
and by making each possible UDP tunnel gro_complete() callback set the
inner_mac_header to the beginning of the tunnel payload.

Signed-off-by: Jarno Rajahalme <redacted>
---
v3: Added setting inner_mac_header from all possible callbacks to cover
    cases where there is no inner mac header.

Alex and Tom, can you please review this new version since you guys had
so much feedback for v2?

I'm okay with the patch.Clarifying exactly what skb->encaspulation
means is future work.

THanks.

From: Jarno Rajahalme <redacted>
Date: Tue,  3 May 2016 16:10:20 -0700

The setting of the UDP tunnel GSO type is already performed by
udp[46]_gro_complete().

Signed-off-by: Jarno Rajahalme <redacted>

Applied.

From: Jarno Rajahalme <redacted>
Date: Tue,  3 May 2016 16:10:21 -0700

UDP tunnel segmentation code relies on the inner offsets being set for
an UDP tunnel GSO packet, but the inner *_complete() functions will
set the inner offsets only if 'encapsulation' is set before calling
them.  Currently, udp_gro_complete() sets 'encapsulation' only after
the inner *_complete() functions are done.  This causes the inner
offsets having invalid values after udp_gro_complete() returns, which
in turn will make it impossible to properly segment the packet in case
it needs to be forwarded, which would be visible to the user either as
invalid packets being sent or as packet loss.

This patch fixes this by setting skb's 'encapsulation' in
udp_gro_complete() before calling into the inner complete functions,
and by making each possible UDP tunnel gro_complete() callback set the
inner_mac_header to the beginning of the tunnel payload.

Signed-off-by: Jarno Rajahalme <redacted>
---
v3: Added setting inner_mac_header from all possible callbacks to cover
    cases where there is no inner mac header.

Applied.