4.19-stable review patch. If anyone has any objections, please let me know.
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From: Jason Wang jasowang@redhat.com
[ Upstream commit e59ff2c49ae16e1d179de679aca81405829aee6c ]
We don't disable VIRTIO_NET_F_GUEST_CSUM if XDP was set. This means we can receive partial csumed packets with metadata kept in the vnet_hdr. This may have several side effects:
- It could be overridden by header adjustment, thus is might be not correct after XDP processing. - There's no way to pass such metadata information through XDP_REDIRECT to another driver. - XDP does not support checksum offload right now.
So simply disable guest csum if possible in this the case of XDP.
Fixes: 3f93522ffab2d ("virtio-net: switch off offloads on demand if possible on XDP set") Reported-by: Jesper Dangaard Brouer brouer@redhat.com Cc: Jesper Dangaard Brouer brouer@redhat.com Cc: Pavel Popa pashinho1990@gmail.com Cc: David Ahern dsahern@gmail.com Signed-off-by: Jason Wang jasowang@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/virtio_net.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
--- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -70,7 +70,8 @@ static const unsigned long guest_offload VIRTIO_NET_F_GUEST_TSO4, VIRTIO_NET_F_GUEST_TSO6, VIRTIO_NET_F_GUEST_ECN, - VIRTIO_NET_F_GUEST_UFO + VIRTIO_NET_F_GUEST_UFO, + VIRTIO_NET_F_GUEST_CSUM };
struct virtnet_stat_desc { @@ -2285,9 +2286,6 @@ static int virtnet_clear_guest_offloads( if (!vi->guest_offloads) return 0;
- if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM)) - offloads = 1ULL << VIRTIO_NET_F_GUEST_CSUM; - return virtnet_set_guest_offloads(vi, offloads); }
@@ -2297,8 +2295,6 @@ static int virtnet_restore_guest_offload
if (!vi->guest_offloads) return 0; - if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_GUEST_CSUM)) - offloads |= 1ULL << VIRTIO_NET_F_GUEST_CSUM;
return virtnet_set_guest_offloads(vi, offloads); }