net: Fix data-races around netdev_max_backlog.

[platform/kernel/linux-rpi.git] / net / core / dev.c

diff --git a/net/core/dev.c b/net/core/dev.c
index 716df64..07da69c 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4624,7 +4624,7 @@ static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
        struct softnet_data *sd;
        unsigned int old_flow, new_flow;
 
-       if (qlen < (netdev_max_backlog >> 1))
+       if (qlen < (READ_ONCE(netdev_max_backlog) >> 1))
                return false;
 
        sd = this_cpu_ptr(&softnet_data);
@@ -4672,7 +4672,7 @@ static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
        if (!netif_running(skb->dev))
                goto drop;
        qlen = skb_queue_len(&sd->input_pkt_queue);
-       if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
+       if (qlen <= READ_ONCE(netdev_max_backlog) && !skb_flow_limit(skb, qlen)) {
                if (qlen) {
 enqueue:
                        __skb_queue_tail(&sd->input_pkt_queue, skb);
@@ -5918,7 +5918,7 @@ static int process_backlog(struct napi_struct *napi, int quota)
                net_rps_action_and_irq_enable(sd);
        }
 
-       napi->weight = dev_rx_weight;
+       napi->weight = READ_ONCE(dev_rx_weight);
        while (again) {
                struct sk_buff *skb;