[PATCH 4.15 068/122] bridge: Fix VLAN reference count problem
From: Greg Kroah-Hartman
Date: Wed Mar 07 2018 - 15:37:48 EST
4.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Ido Schimmel <idosch@xxxxxxxxxxxx>
[ Upstream commit 0e5a82efda872c2469c210957d7d4161ef8f4391 ]
When a VLAN is added on a port, a reference is taken on the
corresponding master VLAN entry. If it does not already exist, then it
is created and a reference taken.
However, in the second case a reference is not really taken when
CONFIG_REFCOUNT_FULL is enabled as refcount_inc() is replaced by
refcount_inc_not_zero().
Fix this by using refcount_set() on a newly created master VLAN entry.
Fixes: 251277598596 ("net, bridge: convert net_bridge_vlan.refcnt from atomic_t to refcount_t")
Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxxxx>
Acked-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/bridge/br_vlan.c | 2 ++
1 file changed, 2 insertions(+)
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -168,6 +168,8 @@ static struct net_bridge_vlan *br_vlan_g
masterv = br_vlan_find(vg, vid);
if (WARN_ON(!masterv))
return NULL;
+ refcount_set(&masterv->refcnt, 1);
+ return masterv;
}
refcount_inc(&masterv->refcnt);