[PATCH v4 1/6] udp: allow header check for dodgy GSO_UDP_L4 packets.

From: Andrew Melnychenko
Date: Thu Dec 01 2022 - 17:48:58 EST


Allow UDP_L4 for robust packets.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Andrew Melnychenko <andrew@xxxxxxxxxx>
---
net/ipv4/udp_offload.c | 3 ++-
net/ipv6/udp_offload.c | 3 ++-
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index 6d1a4bec2614..f65b1a7a0c26 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -387,7 +387,8 @@ 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;
diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c
index 7720d04ed396..057293293e30 100644
--- a/net/ipv6/udp_offload.c
+++ b/net/ipv6/udp_offload.c
@@ -42,7 +42,8 @@ static struct sk_buff *udp6_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, true);

mss = skb_shinfo(skb)->gso_size;
--
2.38.1