From: Xin Long <lucien.xin@xxxxxxxxx> [ Upstream commit bde1b56f898ca8112912d7b36e55e1543b3be0cf ] Without NAPI_GRO_CB(skb)->is_flist initialized, when the dev doesn't support NETIF_F_GRO_FRAGLIST, is_flist can still be set and fraglist will be used in udp_gro_receive(). So fix it by initializing is_flist with 0 in udp_gro_receive. Fixes: 9fd1ff5d2ac7 ("udp: Support UDP fraglist GRO/GSO.") Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> Acked-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/ipv4/udp_offload.c | 1 + 1 file changed, 1 insertion(+) --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -453,6 +453,7 @@ struct sk_buff *udp_gro_receive(struct l unsigned int off = skb_gro_offset(skb); int flush = 1; + NAPI_GRO_CB(skb)->is_flist = 0; if (skb->dev->features & NETIF_F_GRO_FRAGLIST) NAPI_GRO_CB(skb)->is_flist = sk ? !udp_sk(sk)->gro_enabled: 1;