The purpose of commit 703eec1b2422 ("virtio_net: fixing XDP for fully checksummed packets handling") is to record the flags in advance, as their value may be overwritten in the XDP case. However, the flags recorded under big mode are incorrect, because in big mode, the passed buf does not point to the rx buffer, but rather to the page of the submitted buffer. This commit fixes this issue. For the small mode, the commit c11a49d58ad2 ("virtio_net: Fix mismatched buf address when unmapping for small packets") fixed it. Fixes: 703eec1b2422 ("virtio_net: fixing XDP for fully checksummed packets handling") Signed-off-by: Xuan Zhuo Acked-by: Jason Wang --- drivers/net/virtio_net.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 7da5a37917e9..22f7725798e3 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -2620,22 +2620,28 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, return; } - /* 1. Save the flags early, as the XDP program might overwrite them. + /* About the flags below: + * 1. Save the flags early, as the XDP program might overwrite them. * These flags ensure packets marked as VIRTIO_NET_HDR_F_DATA_VALID * stay valid after XDP processing. * 2. XDP doesn't work with partially checksummed packets (refer to * virtnet_xdp_set()), so packets marked as * VIRTIO_NET_HDR_F_NEEDS_CSUM get dropped during XDP processing. */ - flags = ((struct virtio_net_common_hdr *)buf)->hdr.flags; - if (vi->mergeable_rx_bufs) + if (vi->mergeable_rx_bufs) { + flags = ((struct virtio_net_common_hdr *)buf)->hdr.flags; skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit, stats); - else if (vi->big_packets) + } else if (vi->big_packets) { + void *p = page_address((struct page *)buf); + + flags = ((struct virtio_net_common_hdr *)p)->hdr.flags; skb = receive_big(dev, vi, rq, buf, len, stats); - else + } else { + flags = ((struct virtio_net_common_hdr *)buf)->hdr.flags; skb = receive_small(dev, vi, rq, buf, ctx, len, xdp_xmit, stats); + } if (unlikely(!skb)) return; -- 2.32.0.3.g01195cf9f The commit be50da3e9d4a ("net: virtio_net: implement exact header length guest feature") introduces support for the VIRTIO_NET_F_GUEST_HDRLEN feature in virtio-net. This feature requires virtio-net to set hdr_len to the actual header length of the packet when transmitting, the number of bytes from the start of the packet to the beginning of the transport-layer payload. However, in practice, hdr_len was being set using skb_headlen(skb), which is clearly incorrect. This commit fixes that issue. Fixes: be50da3e9d4a ("net: virtio_net: implement exact header length guest feature") Signed-off-by: Xuan Zhuo --- include/linux/virtio_net.h | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index 20e0584db1dd..e059e9c57937 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -217,20 +217,34 @@ static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, if (skb_is_gso(skb)) { struct skb_shared_info *sinfo = skb_shinfo(skb); + u16 hdr_len = 0; + + /* In certain code paths (such as the af_packet.c receive path), + * this function may be called without a transport header. + */ + if (skb_transport_header_was_set(skb)) + hdr_len = skb_transport_offset(skb); - /* This is a hint as to how much should be linear. */ - hdr->hdr_len = __cpu_to_virtio16(little_endian, - skb_headlen(skb)); hdr->gso_size = __cpu_to_virtio16(little_endian, sinfo->gso_size); - if (sinfo->gso_type & SKB_GSO_TCPV4) + if (sinfo->gso_type & SKB_GSO_TCPV4) { hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; - else if (sinfo->gso_type & SKB_GSO_TCPV6) + if (hdr_len) + hdr_len += tcp_hdrlen(skb); + } else if (sinfo->gso_type & SKB_GSO_TCPV6) { hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; - else if (sinfo->gso_type & SKB_GSO_UDP_L4) + if (hdr_len) + hdr_len += tcp_hdrlen(skb); + } else if (sinfo->gso_type & SKB_GSO_UDP_L4) { hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP_L4; - else + if (hdr_len) + hdr_len += sizeof(struct udphdr); + } else { return -EINVAL; + } + + hdr->hdr_len = __cpu_to_virtio16(little_endian, hdr_len); + if (sinfo->gso_type & SKB_GSO_TCP_ECN) hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; } else -- 2.32.0.3.g01195cf9f The commit a2fb4bc4e2a6a03 ("net: implement virtio helpers to handle UDP GSO tunneling.") introduces support for the UDP GSO tunnel feature in virtio-net. The virtio spec says: If the \field{gso_type} has the VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV4 bit or VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV6 bit set, \field{hdr_len} accounts for all the headers up to and including the inner transport. The commit did not update the hdr_len to include the inner transport. Fixes: a2fb4bc4e2a6a03 ("net: implement virtio helpers to handle UDP GSO tunneling.") Signed-off-by: Xuan Zhuo --- include/linux/virtio_net.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index e059e9c57937..765fd5f471a4 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -403,6 +403,7 @@ virtio_net_hdr_tnl_from_skb(const struct sk_buff *skb, struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)vhdr; unsigned int inner_nh, outer_th; int tnl_gso_type; + u16 hdr_len; int ret; tnl_gso_type = skb_shinfo(skb)->gso_type & (SKB_GSO_UDP_TUNNEL | @@ -434,6 +435,23 @@ virtio_net_hdr_tnl_from_skb(const struct sk_buff *skb, outer_th = skb->transport_header - skb_headroom(skb); vhdr->inner_nh_offset = cpu_to_le16(inner_nh); vhdr->outer_th_offset = cpu_to_le16(outer_th); + + switch (skb->inner_ipproto) { + case IPPROTO_TCP: + hdr_len = inner_tcp_hdrlen(skb); + break; + + case IPPROTO_UDP: + hdr_len = sizeof(struct udphdr); + break; + + default: + return -EINVAL; + } + + hdr_len += skb_inner_transport_offset(skb); + hdr->hdr_len = __cpu_to_virtio16(little_endian, hdr_len); + return 0; } -- 2.32.0.3.g01195cf9f