[ Upstream commit 6e6b904ad4f9aed43ec320afbd5a52ed8461ab41 ]

Init the gre_key from tuninfo->key.tun_id and init the mark
from the skb->mark, set the oif to zero in the collect metadata
mode.

Fixes: cfc7381b ("ip_tunnel: add collect_md mode to IPIP tunnel")
Signed-off-by: Nwenxu <wenxu@ucloud.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>