ip6_tunnel: fix potential issue in __ip6_tnl_rcv

When __ip6_tnl_rcv fails, the tun_dst won't be freed, so call
dst_release to free it in error code path.

Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
CC: Alexei Starovoitov <ast@fb.com>
Tested-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index c3581973f5d7..035c0496b92a 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -858,6 +858,8 @@ static int __ip6_tnl_rcv(struct ip6_tnl *tunnel, struct sk_buff *skb,
         return 0;
 
 drop:
+        if (tun_dst)
+                dst_release((struct dst_entry *)tun_dst);
         kfree_skb(skb);
         return 0;
 }