bridge: Correctly clamp MAX forward_delay when enabling STP

[~andy/linux] / net / bridge / br_stp_if.c

diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
index d45e760141bb81a34909b98724b2d8f3fc876136..656a6f3e40de1b13b9ea7a89373da5d5615e5bb2 100644 (file)
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -129,6 +129,14 @@ static void br_stp_start(struct net_bridge *br)
        char *envp[] = { NULL };
 
        r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
+
+       spin_lock_bh(&br->lock);
+
+       if (br->bridge_forward_delay < BR_MIN_FORWARD_DELAY)
+               __br_set_forward_delay(br, BR_MIN_FORWARD_DELAY);
+       else if (br->bridge_forward_delay > BR_MAX_FORWARD_DELAY)
+               __br_set_forward_delay(br, BR_MAX_FORWARD_DELAY);
+
        if (r == 0) {
                br->stp_enabled = BR_USER_STP;
                br_debug(br, "userspace STP started\n");
@@ -137,10 +145,10 @@ static void br_stp_start(struct net_bridge *br)
                br_debug(br, "using kernel STP\n");
 
                /* To start timers on any ports left in blocking */
-               spin_lock_bh(&br->lock);
                br_port_state_selection(br);
-               spin_unlock_bh(&br->lock);
        }
+
+       spin_unlock_bh(&br->lock);
 }
 
 static void br_stp_stop(struct net_bridge *br)