[PATCH AUTOSEL for 4.14 55/67] ip_gre: fix potential memory leak in erspan_rcv

Sasha Levin
2018-03-08T06:38:12Z

From: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>

[ Upstream commit 50670b6ee9bc4ae8f9ce3112b437987adf273245 ]

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

Fixes: 1a66a836da6 ("gre: add collect_md mode to ERSPAN tunnel")
Cc: William Tu <u9012063@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
net/ipv4/ip_gre.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index e0cc6a38b701..5e0e0db341ca 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -303,8 +303,10 @@ static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi,
return PACKET_REJECT;

md = ip_tunnel_info_opts(&tun_dst->u.tun_info);
- if (!md)
+ if (!md) {
+ dst_release((struct dst_entry *)tun_dst);
return PACKET_REJECT;
+ }

md->index = index;
info = &tun_dst->u.tun_info;
--
2.14.1