From: Haiyang Zhang Date: Fri, 22 Feb 2019 18:25:03 +0000 (+0000) Subject: hv_netvsc: Fix IP header checksum for coalesced packets X-Git-Tag: v4.19.28~44 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d61918a5e401bc1911d761a7f0c5c760ea1cac4b;p=platform%2Fkernel%2Flinux-rpi.git hv_netvsc: Fix IP header checksum for coalesced packets [ Upstream commit bf48648d650db1146b75b9bd358502431e86cf4f ] Incoming packets may have IP header checksum verified by the host. They may not have IP header checksum computed after coalescing. This patch re-compute the checksum when necessary, otherwise the packets may be dropped, because Linux network stack always checks it. Signed-off-by: Haiyang Zhang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index c9e2a98..c832040 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -743,6 +743,14 @@ void netvsc_linkstatus_callback(struct net_device *net, schedule_delayed_work(&ndev_ctx->dwork, 0); } +static void netvsc_comp_ipcsum(struct sk_buff *skb) +{ + struct iphdr *iph = (struct iphdr *)skb->data; + + iph->check = 0; + iph->check = ip_fast_csum(iph, iph->ihl); +} + static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net, struct napi_struct *napi, const struct ndis_tcp_ip_checksum_info *csum_info, @@ -766,9 +774,17 @@ static struct sk_buff *netvsc_alloc_recv_skb(struct net_device *net, /* skb is already created with CHECKSUM_NONE */ skb_checksum_none_assert(skb); - /* - * In Linux, the IP checksum is always checked. - * Do L4 checksum offload if enabled and present. + /* Incoming packets may have IP header checksum verified by the host. + * They may not have IP header checksum computed after coalescing. + * We compute it here if the flags are set, because on Linux, the IP + * checksum is always checked. + */ + if (csum_info && csum_info->receive.ip_checksum_value_invalid && + csum_info->receive.ip_checksum_succeeded && + skb->protocol == htons(ETH_P_IP)) + netvsc_comp_ipcsum(skb); + + /* Do L4 checksum offload if enabled and present. */ if (csum_info && (net->features & NETIF_F_RXCSUM)) { if (csum_info->receive.tcp_checksum_succeeded ||