If batadv_v_ogm_init encounters a memory failure, the fields ogm_wq, ogm_buff_mutex and etc. are not initialized. Then the control flow goes to batadv_v_ogm_free due to the error handling code. As a result, the API invocation "cancel_delayed_work_sync" and "mutex_lock" will cause many issues. The crashing stack trace is as follows:

Call Trace: __cancel_work_timer+0x1c9/0x280 kernel/workqueue.c:3170 batadv_v_ogm_free+0x1d/0x50 net/batman-adv/bat_v_ogm.c:1076 batadv_mesh_free+0x35/0xa0 net/batman-adv/main.c:244 batadv_mesh_init+0x22a/0x240 net/batman-adv/main.c:226 batadv_softif_init_late+0x1ad/0x240 net/batman-adv/soft-interface.c:804 register_netdevice+0x15d/0x810 net/core/dev.c:10229

Fixes: a8d23cbbf6c9 ("batman-adv: Avoid free/alloc race when handling OGM2 buffer") Fixes: 0da0035942d4 ("batman-adv: OGMv2 - add basic infrastructure") Signed-off-by: Dongliang Mu mudongliangabcd@gmail.com --- net/batman-adv/bat_v_ogm.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 1d750f3cb2e4..2f3ecbcec58d 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -1044,6 +1044,13 @@ int batadv_v_ogm_init(struct batadv_priv *bat_priv) unsigned char *ogm_buff; u32 random_seqno;

+ /* randomize initial seqno to avoid collision */ + get_random_bytes(&random_seqno, sizeof(random_seqno)); + atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno); + INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send); + + mutex_init(&bat_priv->bat_v.ogm_buff_mutex); + bat_priv->bat_v.ogm_buff_len = BATADV_OGM2_HLEN; ogm_buff = kzalloc(bat_priv->bat_v.ogm_buff_len, GFP_ATOMIC); if (!ogm_buff) @@ -1057,13 +1064,6 @@ int batadv_v_ogm_init(struct batadv_priv *bat_priv) ogm_packet->flags = BATADV_NO_FLAGS; ogm_packet->throughput = htonl(BATADV_THROUGHPUT_MAX_VALUE);

- /* randomize initial seqno to avoid collision */ - get_random_bytes(&random_seqno, sizeof(random_seqno)); - atomic_set(&bat_priv->bat_v.ogm_seqno, random_seqno); - INIT_DELAYED_WORK(&bat_priv->bat_v.ogm_wq, batadv_v_ogm_send); - - mutex_init(&bat_priv->bat_v.ogm_buff_mutex); - return 0; }