anton.ivanov at cambridgegreys.com
2019-Dec-09 10:48 UTC
[PATCH] virtio: Work around frames incorrectly marked as gso
From: Anton Ivanov <anton.ivanov at cambridgegreys.com>
Some of the 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 I tested.
These frames are reported as invalid while they are in fact
gso-less frames.
This patch marks the vnet header as no-GSO for them instead
of reporting it as invalid.
Signed-off-by: Anton Ivanov <anton.ivanov at cambridgegreys.com>
---
include/linux/virtio_net.h | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h
index 0d1fe9297ac6..d90d5cff1b9a 100644
--- a/include/linux/virtio_net.h
+++ b/include/linux/virtio_net.h
@@ -112,8 +112,12 @@ static inline int virtio_net_hdr_from_skb(const struct
sk_buff *skb,
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (sinfo->gso_type & SKB_GSO_TCPV6)
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
- else
- return -EINVAL;
+ else {
+ if (skb->data_len == 0)
+ hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
+ else
+ return -EINVAL;
+ }
if (sinfo->gso_type & SKB_GSO_TCP_ECN)
hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
} else
--
2.20.1
Johannes Berg
2019-Dec-09 10:54 UTC
[PATCH] virtio: Work around frames incorrectly marked as gso
> else if (sinfo->gso_type & SKB_GSO_TCPV6) > hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; > - else > - return -EINVAL; > + else { > + if (skb->data_len == 0) > + hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;maybe use "else if" like in the before? yes, it's a different type of condition, but braces look a bit unnatural here to me at least johannes
Anton Ivanov
2020-Feb-10 16:55 UTC
[PATCH] virtio: Work around frames incorrectly marked as gso
On 09/12/2019 10:48, anton.ivanov at cambridgegreys.com wrote:> From: Anton Ivanov <anton.ivanov at cambridgegreys.com> > > Some of the 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 I tested. > > These frames are reported as invalid while they are in fact > gso-less frames. > > This patch marks the vnet header as no-GSO for them instead > of reporting it as invalid. > > Signed-off-by: Anton Ivanov <anton.ivanov at cambridgegreys.com> > --- > include/linux/virtio_net.h | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h > index 0d1fe9297ac6..d90d5cff1b9a 100644 > --- a/include/linux/virtio_net.h > +++ b/include/linux/virtio_net.h > @@ -112,8 +112,12 @@ static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, > hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; > else if (sinfo->gso_type & SKB_GSO_TCPV6) > hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; > - else > - return -EINVAL; > + else { > + if (skb->data_len == 0) > + hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; > + else > + return -EINVAL; > + } > if (sinfo->gso_type & SKB_GSO_TCP_ECN) > hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; > } else >ping. -- Anton R. Ivanov Cambridgegreys Limited. Registered in England. Company Number 10273661 https://www.cambridgegreys.com/
Jason Wang
2020-Feb-11 02:51 UTC
[PATCH] virtio: Work around frames incorrectly marked as gso
On 2020/2/11 ??12:55, Anton Ivanov wrote:> > > On 09/12/2019 10:48, anton.ivanov at cambridgegreys.com wrote: >> From: Anton Ivanov <anton.ivanov at cambridgegreys.com> >> >> Some of the 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 I tested. >> >> These frames are reported as invalid while they are in fact >> gso-less frames. >> >> This patch marks the vnet header as no-GSO for them instead >> of reporting it as invalid. >> >> Signed-off-by: Anton Ivanov <anton.ivanov at cambridgegreys.com> >> --- >> ? include/linux/virtio_net.h | 8 ++++++-- >> ? 1 file changed, 6 insertions(+), 2 deletions(-) >> >> diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h >> index 0d1fe9297ac6..d90d5cff1b9a 100644 >> --- a/include/linux/virtio_net.h >> +++ b/include/linux/virtio_net.h >> @@ -112,8 +112,12 @@ static inline int virtio_net_hdr_from_skb(const >> struct sk_buff *skb, >> ????????????? hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; >> ????????? else if (sinfo->gso_type & SKB_GSO_TCPV6) >> ????????????? hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; >> -??????? else >> -??????????? return -EINVAL; >> +??????? else { >> +??????????? if (skb->data_len == 0) >> +??????????????? hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; >> +??????????? else >> +??????????????? return -EINVAL; >> +??????? } >> ????????? if (sinfo->gso_type & SKB_GSO_TCP_ECN) >> ????????????? hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN; >> ????? } else >> > > ping. >Do you mean gso_size is set but gso_type is not? Looks like a bug elsewhere. Thanks