[PATCH 2/2] ip6_gre: fix potential memory leak in ip6erspan_rcv

[Haishuang Yan]

If md is NULL, tun_dst must be freed, otherwise it will cause memory
leak

Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Cc: William Tu <u9012...@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishu...@cmss.chinamobile.com>
---
 net/ipv6/ip6_gre.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 4562579..b8b0e4b 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -542,8 +542,10 @@ static int ip6erspan_rcv(struct sk_buff *skb, int 
gre_hdr_len,
 
                        info = &tun_dst->u.tun_info;
                        md = ip_tunnel_info_opts(info);
-                       if (!md)
+                       if (!md) {
+                               dst_release((struct dst_entry *)tun_dst);
                                return PACKET_REJECT;
+                       }
 
                        md->index = index;
                        info->key.tun_flags |= TUNNEL_ERSPAN_OPT;
-- 
1.8.3.1