1 files changed, 1 insertions, 1 deletions

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 28863570dd60..d84dc8d4c916 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -455,7 +455,7 @@ static netdev_tx_t reg_vif_xmit(struct sk_buff *skb, struct net_device *dev)
         struct mr_table *mrt;
         struct flowi4 fl4 = {
                 .flowi4_oif     = dev->ifindex,
-                .flowi4_iif     = skb->skb_iif,
+                .flowi4_iif     = skb->skb_iif ? : LOOPBACK_IFINDEX,
                 .flowi4_mark    = skb->mark,
         };
         int err;