From: Sven Eckelmann <sven@xxxxxxxxxxxxx> commit 9f460ae31c4435fd022c443a6029352217a16ac1 upstream. The soft/batadv interface for a queued OGM can be changed during the time the OGM was queued for transmission and when the OGM is actually transmitted by the worker. But WARN_ON must be used to denote kernel bugs and not to print simple warnings. A warning can simply be printed using pr_warn. Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Reported-by: syzbot+c0b807de416427ff3dd1@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: ef0a937f7a14 ("batman-adv: consider outgoing interface in OGM sending") Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx> Signed-off-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx> [ bp: 4.4 backported: adjust context. ] Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/batman-adv/bat_iv_ogm.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -526,8 +526,10 @@ static void batadv_iv_ogm_emit(struct ba if (WARN_ON(!forw_packet->if_outgoing)) goto out; - if (WARN_ON(forw_packet->if_outgoing->soft_iface != soft_iface)) + if (forw_packet->if_outgoing->soft_iface != soft_iface) { + pr_warn("%s: soft interface switch for queued OGM\n", __func__); goto out; + } if (forw_packet->if_incoming->if_status != BATADV_IF_ACTIVE) goto out;