mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2026-08-09 06:14:34 +02:00
When vhost owns the virtio-net header, i.e. when VHOST_NET_F_VIRTIO_NET_HDR is negotiated, sock_hlen is 0, meaning that no header will be forwarded to the TAP device. In the current vhost_net_build_xdp() implementation, when sock_hlen == 0, the gso pointer can point at the start of the Ethernet frame instead of a virtio-net header. This results in a wrong interpretation of the destination MAC address bytes as struct virtio_net_hdr fields. This can, for some MAC addresses, trigger -EINVAL and return early before the TX descriptor is completed, which can stall vhost-net TX. Before97b2409f28, the gso pointer was set to the zeroed padding area, using it as a synthetic virtio-net header. Restore that behavior. Fixes:97b2409f28("vhost-net: reduce one userspace copy when building XDP buff") Signed-off-by: Enrico Zanda <enrico.zanda@arm.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Link: https://patch.msgid.link/20260708152242.2268848-1-enrico.zanda@arm.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>