net: accept UFOv6 packages in virtio_net_hdr_to_skb

stable inclusion
from stable-v5.10.89
commit ed05e4dcfba63bcca36ec1d19d099a1ec6b000ec
bugzilla: 186140 https://gitee.com/openeuler/kernel/issues/I4S8HA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=ed05e4dcfba63bcca36ec1d19d099a1ec6b000ec

--------------------------------

[ Upstream commit 7e5cced9 ]

Skb with skb->protocol 0 at the time of virtio_net_hdr_to_skb may have
a protocol inferred from virtio_net_hdr with virtio_net_hdr_set_proto.

Unlike TCP, UDP does not have separate types for IPv4 and IPv6. Type
VIRTIO_NET_HDR_GSO_UDP is guessed to be IPv4/UDP. As of the below
commit, UFOv6 packets are dropped due to not matching the protocol as
obtained from dev_parse_header_protocol.

Invert the test to take that L2 protocol field as starting point and
pass both UFOv4 and UFOv6 for VIRTIO_NET_HDR_GSO_UDP.

Fixes: 924a9bc3 ("net: check if protocol extracted by virtio_net_hdr_set_proto is correct")
Link: https://lore.kernel.org/netdev/CABcq3pG9GRCYqFDBAJ48H1vpnnX=41u+MhQnayF1ztLH4WX0Fw@mail.gmail.com/


Reported-by: Andrew Melnichenko <andrew@daynix.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20211220144901.2784030-1-willemdebruijn.kernel@gmail.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>