Although `virtio_net_hdr_from_skb` is used in several places outside of
`virtio-net.c`, the `hdr_len` field is only utilized by the device
according to the specification. Therefore, we do not need to set
`hdr_len` unless the header is actually passed to the device.

Signed-off-by: Xuan Zhuo <[email protected]>
---
 include/linux/virtio_net.h | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h
index 4d1780848d0e..710ae0d2d336 100644
--- a/include/linux/virtio_net.h
+++ b/include/linux/virtio_net.h
@@ -218,9 +218,14 @@ 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);
 
-               /* This is a hint as to how much should be linear. */
-               hdr->hdr_len = __cpu_to_virtio16(little_endian,
-                                                skb_headlen(skb));
+               /* In certain code paths (such as the af_packet.c receive path),
+                * this function may be called without a transport header.
+                * In this case, we do not need to set the hdr_len.
+                */
+               if (skb_transport_header_was_set(skb))
+                       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)
-- 
2.32.0.3.g01195cf9f


Reply via email to