From 929946a471c1d5c6c595b4094f4c56bdfceee9c7 Mon Sep 17 00:00:00 2001
From: Alexander Aring <aar@pengutronix.de>
Date: Tue, 21 Jun 2016 10:27:18 +0200
Subject: [PATCH] 6lowpan: ndisc: fix double read unlock

This patch removes a double unlock case to accessing neighbour private
data.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
---
 net/6lowpan/ndisc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/6lowpan/ndisc.c b/net/6lowpan/ndisc.c
index ae1d4199aa4c..030504e031b6 100644
--- a/net/6lowpan/ndisc.c
+++ b/net/6lowpan/ndisc.c
@@ -135,8 +135,9 @@ static int lowpan_ndisc_opt_addr_space(const struct net_device *dev,
 			read_unlock_bh(&neigh->lock);
 			addr_space += __ndisc_opt_addr_space(IEEE802154_SHORT_ADDR_LEN, 0);
 			*ha = ha_buf;
+		} else {
+			read_unlock_bh(&neigh->lock);
 		}
-		read_unlock_bh(&neigh->lock);
 		break;
 	case NDISC_NEIGHBOUR_ADVERTISEMENT:
 	case NDISC_NEIGHBOUR_SOLICITATION:
-- 
2.20.1