On Mon, Feb 24, 2020 at 01:25:50PM +0000, [email protected] wrote: > From: Anton Ivanov <[email protected]> > > Some of the locally generated frames marked as GSO which > arrive at virtio_net_hdr_from_skb() have no GSO_TYPE, no > fragments (data_len = 0) and length significantly shorter > than the MTU (752 in my experiments). > > This is observed on raw sockets reading off vEth interfaces > in all 4.x and 5.x kernels. The frames are reported as > invalid, while they are in fact gso-less frames. > > The easiest way to reproduce is to connect a User Mode > Linux instance to the host using the vector raw transport > and a vEth interface. Vector raw uses recvmmsg/sendmmsg > with virtio headers on af_packet sockets. When running iperf > between the UML and the host, UML regularly complains about > EINVAL return from recvmmsg. > > This patch marks the vnet header as non-GSO instead of > reporting it as invalid. > > Signed-off-by: Anton Ivanov <[email protected]>
Reviewed-by: Michael S. Tsirkin <[email protected]> > --- > include/linux/virtio_net.h | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h > index 0d1fe9297ac6..2c99c752cb20 100644 > --- a/include/linux/virtio_net.h > +++ b/include/linux/virtio_net.h > @@ -98,10 +98,11 @@ static inline int virtio_net_hdr_from_skb(const struct > sk_buff *skb, > bool has_data_valid, > int vlan_hlen) > { > + struct skb_shared_info *sinfo = skb_shinfo(skb); > + > memset(hdr, 0, sizeof(*hdr)); /* no info leak */ > > - if (skb_is_gso(skb)) { > - struct skb_shared_info *sinfo = skb_shinfo(skb); > + if (skb_is_gso(skb) && sinfo->gso_type) { > > /* This is a hint as to how much should be linear. */ > hdr->hdr_len = __cpu_to_virtio16(little_endian, > -- > 2.20.1 _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
