[PATCH net-next v3 5/8] vxlan: allow L4 GRO passthrough

[Paolo Abeni]

When passing up an UDP GSO packet with L4 aggregation, there is
no need to segment it at the vxlan level. We can propagate the
packet untouched and let it be segmented later, if needed.

Introduce an helper to allow let the UDP socket to accept any
L4 aggregation and use it in the vxlan driver.

v1 -> v2:
 - updated to use the newly introduced UDP socket 'accept*' fields

Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
 drivers/net/vxlan.c | 1 +
 include/linux/udp.h | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 7665817f3cb61..39ee1300cdd9d 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -3484,6 +3484,7 @@ static struct socket *vxlan_create_sock(struct net *net, 
bool ipv6,
        if (err < 0)
                return ERR_PTR(err);
 
+       udp_allow_gso(sock->sk);
        return sock;
 }
 
diff --git a/include/linux/udp.h b/include/linux/udp.h
index ae58ff3b6b5b8..ae66dadd85434 100644
--- a/include/linux/udp.h
+++ b/include/linux/udp.h
@@ -145,6 +145,12 @@ static inline bool udp_unexpected_gso(struct sock *sk, 
struct sk_buff *skb)
        return false;
 }
 
+static inline void udp_allow_gso(struct sock *sk)
+{
+       udp_sk(sk)->accept_udp_l4 = 1;
+       udp_sk(sk)->accept_udp_fraglist = 1;
+}
+
 #define udp_portaddr_for_each_entry(__sk, list) \
        hlist_for_each_entry(__sk, list, __sk_common.skc_portaddr_node)
 
-- 
2.26.2