if (unlikely(hdr->hdr.gso_type))
goto err_xdp;
+ /* Partially checksummed packets must be dropped. */
+ if (unlikely(hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM))
+ goto err_xdp;
+
buflen = SKB_DATA_ALIGN(GOOD_PACKET_LEN + headroom) +
SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
if (unlikely(hdr->hdr.gso_type))
return NULL;
+ /* Partially checksummed packets must be dropped. */
+ if (unlikely(hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM))
+ return NULL;
+
/* Now XDP core assumes frag size is PAGE_SIZE, but buffers
* with headroom may add hole in truesize, which
* make their length exceed PAGE_SIZE. So we disabled the
struct net_device *dev = vi->dev;
struct sk_buff *skb;
struct virtio_net_common_hdr *hdr;
+ u8 flags;
if (unlikely(len < vi->hdr_len + ETH_HLEN)) {
pr_debug("%s: short packet %i\n", dev->name, len);
return;
}
+ /* 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)
skb = receive_mergeable(dev, vi, rq, buf, ctx, len, xdp_xmit,
stats);
if (dev->features & NETIF_F_RXHASH && vi->has_rss_hash_report)
virtio_skb_set_hash(&hdr->hash_v1_hdr, skb);
- if (hdr->hdr.flags & VIRTIO_NET_HDR_F_DATA_VALID)
+ if (flags & VIRTIO_NET_HDR_F_DATA_VALID)
skb->ip_summed = CHECKSUM_UNNECESSARY;
if (virtio_net_hdr_to_skb(skb, &hdr->hdr,