From 69165193ace2823e9bdca9b544e5fb8dbab27209 Mon Sep 17 00:00:00 2001 From: Sven Eckelmann Date: Sat, 5 Mar 2016 16:09:21 +0100 Subject: batman-adv: Use kref_get for batadv_nc_get_nc_node commit 0de32ceee156787429035c974316f4e5098cf722 upstream. batadv_nc_get_nc_node requires that the caller already has a valid reference for orig_neigh_node. It is therefore not possible that it has an reference counter of 0 and was still given to this function The kref_get function instead WARNs (with debug information) when the reference counter would still be 0. This makes a bug in batman-adv better visible because kref_get_unless_zero would have ignored this problem. Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli [bwh: Backported to 3.16: Reference counts are not krefs here, so open- code the equivalent of kref_get()] Signed-off-by: Ben Hutchings --- net/batman-adv/network-coding.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) (limited to 'net/batman-adv') diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 4e718162a26b..33ce5723a1a4 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -813,8 +813,7 @@ static struct batadv_nc_node if (!nc_node) return NULL; - if (!atomic_inc_not_zero(&orig_neigh_node->refcount)) - goto free; + WARN_ON_ONCE(atomic_inc_return(&orig_neigh_node->refcount) < 2); /* Initialize nc_node */ INIT_LIST_HEAD(&nc_node->list); @@ -840,10 +839,6 @@ static struct batadv_nc_node spin_unlock_bh(lock); return nc_node; - -free: - kfree(nc_node); - return NULL; } /** -- cgit v1.2.3