[PATCH v3 1/6] udp: allow header check for dodgy GSO_UDP_L4 packets.

From: Andrew Melnychenko
Date: Wed Sep 07 2022 - 08:51:53 EST


Packets from TAP devices with USO offload converts
to GSO_UDP_L4 & GSO_DODGY sk buffers.
Added changes allow skipping segmentation for DODGY/ROBUST packets.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Andrew Melnychenko <andrew@xxxxxxxxxx>
---
net/ipv4/udp_offload.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 6d1a4bec2614..8e002419b4d5 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -387,7 +387,7 @@ static struct sk_buff *udp4_ufo_fragment(struct sk_buff *skb,
if (!pskb_may_pull(skb, sizeof(struct udphdr)))
goto out;

- if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4 && !skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST))
return __udp_gso_segment(skb, features, false);

mss = skb_shinfo(skb)->gso_size;
--
2.37.2