4 files changed, 12 insertions, 2 deletions

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 30b88777c3df..5ee1a3682bf2 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -134,6 +134,10 @@ struct sk_buff *br_handle_frame(struct net_bridge_port *p, struct sk_buff *skb)
                 if (skb->protocol == htons(ETH_P_PAUSE))
                         goto drop;
 
+                /* If STP is turned off, then forward */
+                if (p->br->stp_enabled == BR_NO_STP && dest[5] == 0)
+                        goto forward;
+
                 if (NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev,
                             NULL, br_handle_local_finish))
                         return NULL;    /* frame consumed by filter */
@@ -141,6 +145,7 @@ struct sk_buff *br_handle_frame(struct net_bridge_port *p, struct sk_buff *skb)
                         return skb;     /* continue processing */
         }
 
+forward:
         switch (p->state) {
         case BR_STATE_FORWARDING:
                 rhook = rcu_dereference(br_should_route_hook);
diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index 6e63ec3f1fcf..0660515f3992 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -297,6 +297,9 @@ void br_topology_change_detection(struct net_bridge *br)
 {
         int isroot = br_is_root_bridge(br);
 
+        if (br->stp_enabled != BR_KERNEL_STP)
+                return;
+
         pr_info("%s: topology change detected, %s\n", br->dev->name,
                 isroot ? "propagating" : "sending tcn bpdu");
 
diff --git a/net/bridge/br_sysfs_br.c b/net/bridge/br_sysfs_br.c
index 603d89248e71..ee4820aa1843 100644
--- a/net/bridge/br_sysfs_br.c
+++ b/net/bridge/br_sysfs_br.c
@@ -172,7 +172,8 @@ static ssize_t store_stp_state(struct device *d,
         if (endp == buf)
                 return -EINVAL;
 
-        rtnl_lock();
+        if (!rtnl_trylock())
+                return restart_syscall();
         br_stp_set_enabled(br, val);
         rtnl_unlock();
 
diff --git a/net/bridge/br_sysfs_if.c b/net/bridge/br_sysfs_if.c
index 02b2d50cce4d..4a3cdf8f3813 100644
--- a/net/bridge/br_sysfs_if.c
+++ b/net/bridge/br_sysfs_if.c
@@ -189,7 +189,8 @@ static ssize_t brport_store(struct kobject * kobj,
 
         val = simple_strtoul(buf, &endp, 0);
         if (endp != buf) {
-                rtnl_lock();
+                if (!rtnl_trylock())
+                        return restart_syscall();
                 if (p->dev && p->br && brport_attr->store) {
                         spin_lock_bh(&p->br->lock);
                         ret = brport_attr->store(p, val);