When a batadv_hard_iface is disabled, its mesh_iface pointer is set to NULL. However, batadv_v_ogm_send_meshif() may still dispatch OGMs via batadv_v_ogm_queue_on_if() for interfaces that have since lost their mesh_iface association. This results in a NULL pointer dereference when batadv_v_ogm_queue_on_if() unconditionally calls netdev_priv() on the now NULL hard_iface->mesh_iface to retrieve the batadv_priv.
It is necessary to ensure that the batadv_v_ogm_queue_on_if() checks that it is using the same mesh_iface for which batadv_v_ogm_send_meshif() was called. Cc: [email protected] Fixes: 0da0035942d4 ("batman-adv: OGMv2 - add basic infrastructure") Reported-by: Yuan Tan <[email protected]> Reported-by: Yifan Wu <[email protected]> Reported-by: Juefei Pu <[email protected]> Reported-by: Xin Liu <[email protected]> Signed-off-by: Sven Eckelmann <[email protected]> --- net/batman-adv/bat_v_ogm.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c index 9914346a..99a2ce9f 100644 --- a/net/batman-adv/bat_v_ogm.c +++ b/net/batman-adv/bat_v_ogm.c @@ -232,13 +232,16 @@ static void batadv_v_ogm_aggr_send(struct batadv_hard_iface *hard_iface) /** * batadv_v_ogm_queue_on_if() - queue a batman ogm on a given interface + * @bat_priv: the bat priv with all the mesh interface information * @skb: the OGM to queue * @hard_iface: the interface to queue the OGM on */ -static void batadv_v_ogm_queue_on_if(struct sk_buff *skb, +static void batadv_v_ogm_queue_on_if(struct batadv_priv *bat_priv, + struct sk_buff *skb, struct batadv_hard_iface *hard_iface) { - struct batadv_priv *bat_priv = netdev_priv(hard_iface->mesh_iface); + if (hard_iface->mesh_iface != bat_priv->mesh_iface) + return; if (!atomic_read(&bat_priv->aggregated_ogms)) { batadv_v_ogm_send_to_if(skb, hard_iface); @@ -344,7 +347,7 @@ static void batadv_v_ogm_send_meshif(struct batadv_priv *bat_priv) break; } - batadv_v_ogm_queue_on_if(skb_tmp, hard_iface); + batadv_v_ogm_queue_on_if(bat_priv, skb_tmp, hard_iface); batadv_hardif_put(hard_iface); } rcu_read_unlock(); @@ -579,7 +582,7 @@ static void batadv_v_ogm_forward(struct batadv_priv *bat_priv, if_outgoing->net_dev->name, ntohl(ogm_forward->throughput), ogm_forward->ttl, if_incoming->net_dev->name); - batadv_v_ogm_queue_on_if(skb, if_outgoing); + batadv_v_ogm_queue_on_if(bat_priv, skb, if_outgoing); out: batadv_orig_ifinfo_put(orig_ifinfo); -- 2.47.3
