[PATCH v3 1/2] ip_tunnel: fix potential issue in ip_tunnel_rcv

[Haishuang Yan]

When ip_tunnel_rcv fails, the tun_dst won't be freed, so call
dst_release to free it in error code path.

CC: Pravin B Shelar <pshelar@xxxxxxxxxx>
Fixes: 2e15ea390e6f ("ip_gre: Add support to collect tunnel metadata.")
Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>

---
Changes in v2:
  - Add the the missing Fixes information
Changes in v3:
  - Free tun_dst from error code path
---
 net/ipv4/ip_tunnel.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index b878ecb..0f1d876 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -446,6 +446,8 @@ int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
 	return 0;
 
 drop:
+	if (tun_dst)
+		dst_release((struct dst_entry *)tun_dst);
 	kfree_skb(skb);
 	return 0;
 }
-- 
1.8.3.1