From 9f735b6f8a77d7be7f8b0765dc93587774832cb1 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 5 Jul 2025 17:06:21 +0200 Subject: [PATCH] net: fix segmentation after TCP/UDP fraglist GRO Since "net: gro: use cb instead of skb->network_header", the skb network header is no longer set in the GRO path. This breaks fraglist segmentation, which relies on ip_hdr()/tcp_hdr() to check for address/port changes. Fix this regression by selectively setting the network header for merged segment skbs. Fixes: 186b1ea73ad8 ("net: gro: use cb instead of skb->network_header") Signed-off-by: Felix Fietkau Reviewed-by: Willem de Bruijn Link: https://patch.msgid.link/20250705150622.10699-1-nbd@nbd.name Signed-off-by: Paolo Abeni --- net/ipv4/tcp_offload.c | 1 + net/ipv4/udp_offload.c | 1 + 2 files changed, 2 insertions(+) diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c index d293087b426df..be5c2294610e5 100644 --- a/net/ipv4/tcp_offload.c +++ b/net/ipv4/tcp_offload.c @@ -359,6 +359,7 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb, flush |= skb->ip_summed != p->ip_summed; flush |= skb->csum_level != p->csum_level; flush |= NAPI_GRO_CB(p)->count >= 64; + skb_set_network_header(skb, skb_gro_receive_network_offset(skb)); if (flush || skb_gro_receive_list(p, skb)) mss = 1; diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 85b5aa82d7d74..e0a6bfa95118a 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -767,6 +767,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head, NAPI_GRO_CB(skb)->flush = 1; return NULL; } + skb_set_network_header(skb, skb_gro_receive_network_offset(skb)); ret = skb_gro_receive_list(p, skb); } else { skb_gro_postpull_rcsum(skb, uh, -- 2.47.2