4.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> [ Upstream commit aeb073241fe7a2b932e04e20c60e47718332877f ] When the transition of NO_STP -> KERNEL_STP was fixed by always calling mod_timer in br_stp_start, it introduced a new regression which causes the timer to be armed even when the bridge is down, and since we stop the timers in its ndo_stop() function, they never get disabled if the device is destroyed before it's upped. To reproduce: $ while :; do ip l add br0 type bridge hello_time 100; brctl stp br0 on; ip l del br0; done; CC: Xin Long <lucien.xin@xxxxxxxxx> CC: Ivan Vecera <cera@xxxxxxx> CC: Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx> Reported-by: Sebastian Ott <sebott@xxxxxxxxxxxxxxxxxx> Fixes: 6d18c732b95c ("bridge: start hello_timer when enabling KERNEL_STP in br_stp_start") Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/bridge/br_stp_if.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -179,7 +179,8 @@ static void br_stp_start(struct net_brid br_debug(br, "using kernel STP\n"); /* To start timers on any ports left in blocking */ - mod_timer(&br->hello_timer, jiffies + br->hello_time); + if (br->dev->flags & IFF_UP) + mod_timer(&br->hello_timer, jiffies + br->hello_time); br_port_state_selection(br); }