[PATCH net v2 1/2] batman-adv: reject new tp_meter sessions during teardown

[Ren Wei <n05ec@lzu.edu.cn>]

From: Jiexun Wang <wangjiexun2025@gmail.com>

Prevent tp_meter from starting new sender or receiver sessions after
mesh_state has left BATADV_MESH_ACTIVE.

Fixes: 33a3bb4a3345 ("batman-adv: throughput meter implementation")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Co-developed-by: Luxing Yin <tr0jan@lzu.edu.cn>
Signed-off-by: Luxing Yin <tr0jan@lzu.edu.cn>
Signed-off-by: Jiexun Wang <wangjiexun2025@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
---
Changes in v2:
- Split the original fix into setup-side and teardown-side patches

 net/batman-adv/tp_meter.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/net/batman-adv/tp_meter.c b/net/batman-adv/tp_meter.c
index 2e42f6b348c8..d9a80e459c2e 100644
--- a/net/batman-adv/tp_meter.c
+++ b/net/batman-adv/tp_meter.c
@@ -947,6 +947,13 @@ void batadv_tp_start(struct batadv_priv *bat_priv, const u8 *dst,
 
 	/* look for an already existing test towards this node */
 	spin_lock_bh(&bat_priv->tp_list_lock);
+	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE) {
+		spin_unlock_bh(&bat_priv->tp_list_lock);
+		batadv_tp_batctl_error_notify(BATADV_TP_REASON_DST_UNREACHABLE,
+					      dst, bat_priv, session_cookie);
+		return;
+	}
+
 	tp_vars = batadv_tp_list_find(bat_priv, dst);
 	if (tp_vars) {
 		spin_unlock_bh(&bat_priv->tp_list_lock);
@@ -1329,9 +1336,12 @@ static struct batadv_tp_vars *
 batadv_tp_init_recv(struct batadv_priv *bat_priv,
 		    const struct batadv_icmp_tp_packet *icmp)
 {
-	struct batadv_tp_vars *tp_vars;
+	struct batadv_tp_vars *tp_vars = NULL;
 
 	spin_lock_bh(&bat_priv->tp_list_lock);
+	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
+		goto out_unlock;
+
 	tp_vars = batadv_tp_list_find_session(bat_priv, icmp->orig,
 					      icmp->session);
 	if (tp_vars)
@@ -1464,6 +1474,9 @@ void batadv_tp_meter_recv(struct batadv_priv *bat_priv, struct sk_buff *skb)
 {
 	struct batadv_icmp_tp_packet *icmp;
 
+	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
+		goto out;
+
 	icmp = (struct batadv_icmp_tp_packet *)skb->data;
 
 	switch (icmp->subtype) {
@@ -1478,6 +1491,8 @@ void batadv_tp_meter_recv(struct batadv_priv *bat_priv, struct sk_buff *skb)
 			   "Received unknown TP Metric packet type %u\n",
 			   icmp->subtype);
 	}
+
+out:
 	consume_skb(skb);
 }
 
-- 
2.34.1