GRO-GSO path is supposed to be transparent and as such L3 flush checks are relevant to all flows which call skb_gro_receive. This patch uses the same logic and code from tcp_gro_receive but in the relevant flow path in udp_gro_receive_segment. Fixes: 36707061d6ba ("udp: allow forwarding of plain (non-fraglisted) UDP GRO packets") Signed-off-by: Richard Gobert <richardbgobert@xxxxxxxxx> --- net/ipv4/udp_offload.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 3498dd1d0694..1f4e08f43c4b 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -471,6 +471,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head, struct sk_buff *p; unsigned int ulen; int ret = 0; + int flush; /* requires non zero csum, for symmetry with GSO */ if (!uh->check) { @@ -528,7 +529,17 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head, skb_gro_postpull_rcsum(skb, uh, sizeof(struct udphdr)); - ret = skb_gro_receive(p, skb); + flush = NAPI_GRO_CB(p)->flush; + + if (NAPI_GRO_CB(p)->flush_id != 1 || + NAPI_GRO_CB(p)->count != 1 || + !NAPI_GRO_CB(p)->is_atomic) + flush |= NAPI_GRO_CB(p)->flush_id; + else + NAPI_GRO_CB(p)->is_atomic = false; + + if (flush || skb_gro_receive(p, skb)) + ret = 1; } } -- 2.36.1