From: Taehee Yoo <ap420073@xxxxxxxxx> [ Upstream commit 989918482bbccbbce3ba2bb9156eb4c193319983 ] amt->nr_tunnels is protected by amt->lock. But, amt_request_handler() has been using this variable without the amt->lock. So, it expands context of amt->lock in the amt_request_handler() to protect amt->nr_tunnels variable. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo <ap420073@xxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/amt.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/amt.c b/drivers/net/amt.c index 4277924ab3b9..acf5ea96652f 100644 --- a/drivers/net/amt.c +++ b/drivers/net/amt.c @@ -2679,7 +2679,9 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb) if (tunnel->ip4 == iph->saddr) goto send; + spin_lock_bh(&amt->lock); if (amt->nr_tunnels >= amt->max_tunnels) { + spin_unlock_bh(&amt->lock); icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0); return true; } @@ -2687,8 +2689,10 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb) tunnel = kzalloc(sizeof(*tunnel) + (sizeof(struct hlist_head) * amt->hash_buckets), GFP_ATOMIC); - if (!tunnel) + if (!tunnel) { + spin_unlock_bh(&amt->lock); return true; + } tunnel->source_port = udph->source; tunnel->ip4 = iph->saddr; @@ -2701,10 +2705,9 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb) INIT_DELAYED_WORK(&tunnel->gc_wq, amt_tunnel_expire); - spin_lock_bh(&amt->lock); list_add_tail_rcu(&tunnel->list, &amt->tunnel_list); tunnel->key = amt->key; - amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true); + __amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true); amt->nr_tunnels++; mod_delayed_work(amt_wq, &tunnel->gc_wq, msecs_to_jiffies(amt_gmi(amt))); -- 2.35.1