From 5ba7dcfe77037b67016263ea597a8b431692ecab Mon Sep 17 00:00:00 2001
From: Sven Eckelmann <sven@narfation.org>
Date: Sun, 3 Dec 2017 11:26:45 +0100
Subject: [PATCH] batman-adv: Fix lock for ogm cnt access in batadv_iv_ogm_calc_tq
Git-commit: 5ba7dcfe77037b67016263ea597a8b431692ecab
Patch-mainline: v4.15-rc4
References: bsc#1051510

The originator node object orig_neigh_node is used to when accessing the
bcast_own(_sum) and real_packet_count information. The access to them has
to be protected with the spinlock in orig_neigh_node.

But the function uses the lock in orig_node instead. This is incorrect
because they could be two different originator node objects.

Fixes: 0ede9f41b217 ("batman-adv: protect bit operations to count OGMs with spinlock")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 net/batman-adv/bat_iv_ogm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 1b659ab652fb..bbe8414b6ee7 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1214,7 +1214,7 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 	orig_node->last_seen = jiffies;
 
 	/* find packet count of corresponding one hop neighbor */
-	spin_lock_bh(&orig_node->bat_iv.ogm_cnt_lock);
+	spin_lock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
 	if_num = if_incoming->if_num;
 	orig_eq_count = orig_neigh_node->bat_iv.bcast_own_sum[if_num];
 	neigh_ifinfo = batadv_neigh_ifinfo_new(neigh_node, if_outgoing);
@@ -1224,7 +1224,7 @@ static bool batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node,
 	} else {
 		neigh_rq_count = 0;
 	}
-	spin_unlock_bh(&orig_node->bat_iv.ogm_cnt_lock);
+	spin_unlock_bh(&orig_neigh_node->bat_iv.ogm_cnt_lock);
 
 	/* pay attention to not get a value bigger than 100 % */
 	if (orig_eq_count > neigh_rq_count)
-- 
2.18.0