From 8e8ce08198de193e3d21d42e96945216e3d9ac7f Mon Sep 17 00:00:00 2001
From: Sven Eckelmann <sven@narfation.org>
Date: Sun, 16 Feb 2020 13:02:06 +0100
Subject: [PATCH] batman-adv: Don't schedule OGM for disabled interface
Git-commit: 8e8ce08198de193e3d21d42e96945216e3d9ac7f
Patch-mainline: v5.6-rc6
References: bsc#1051510
A transmission scheduling for an interface which is currently dropped by
batadv_iv_ogm_iface_disable could still be in progress. The B.A.T.M.A.N. V
is simply cancelling the workqueue item in an synchronous way but this is
not possible with B.A.T.M.A.N. IV because the OGM submissions are
intertwined.
Instead it has to stop submitting the OGM when it detect that the buffer
pointer is set to NULL.
Reported-by: syzbot+a98f2016f40b9cd3818a@syzkaller.appspotmail.com
Reported-by: syzbot+ac36b6a33c28a491e929@syzkaller.appspotmail.com
Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Cc: Hillf Danton <hdanton@sina.com>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
net/batman-adv/bat_iv_ogm.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -932,6 +932,10 @@ static void batadv_iv_ogm_schedule(struc
(hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
return;
+ /* interface already disabled by batadv_iv_ogm_iface_disable */
+ if (!*ogm_buff)
+ return;
+
/* the interface gets activated here to avoid race conditions between
* the moment of activating the interface in
* hardif_activate_interface() where the originator mac is set and