1 files changed, 36 insertions, 32 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 8e6f22961206..fa53830d0683 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1100,7 +1100,7 @@ static int dev_alloc_name_ns(struct net *net,
 	BUG_ON(!net);
 	ret = __dev_alloc_name(net, name, buf);
 	if (ret >= 0)
-		strlcpy(dev->name, buf, IFNAMSIZ);
+		strscpy(dev->name, buf, IFNAMSIZ);
 	return ret;
 }
 
@@ -1137,7 +1137,7 @@ static int dev_get_valid_name(struct net *net, struct net_device *dev,
 	else if (netdev_name_in_use(net, name))
 		return -EEXIST;
 	else if (dev->name != name)
-		strlcpy(dev->name, name, IFNAMSIZ);
+		strscpy(dev->name, name, IFNAMSIZ);
 
 	return 0;
 }
@@ -3927,7 +3927,7 @@ int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
 	skb->pkt_type = PACKET_LOOPBACK;
 	if (skb->ip_summed == CHECKSUM_NONE)
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
-	WARN_ON(!skb_dst(skb));
+	DEBUG_NET_WARN_ON_ONCE(!skb_dst(skb));
 	skb_dst_force(skb);
 	netif_rx(skb);
 	return 0;
@@ -4168,6 +4168,7 @@ int __dev_queue_xmit(struct sk_buff *skb, struct net_device *sb_dev)
 	bool again = false;
 
 	skb_reset_mac_header(skb);
+	skb_assert_len(skb);
 
 	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
 		__skb_tstamp_tx(skb, NULL, NULL, skb->sk, SCM_TSTAMP_SCHED);
@@ -4623,7 +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);
@@ -4671,7 +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);
@@ -4863,7 +4864,10 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 }
 
 /* When doing generic XDP we have to bypass the qdisc layer and the
- * network taps in order to match in-driver-XDP behavior.
+ * network taps in order to match in-driver-XDP behavior. This also means
+ * that XDP packets are able to starve other packets going through a qdisc,
+ * and DDOS attacks will be more effective. In-driver-XDP use dedicated TX
+ * queues, so they do not have this starvation issue.
  */
 void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 {
@@ -4875,7 +4879,7 @@ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 	txq = netdev_core_pick_tx(dev, skb, NULL);
 	cpu = smp_processor_id();
 	HARD_TX_LOCK(dev, txq, cpu);
-	if (!netif_xmit_stopped(txq)) {
+	if (!netif_xmit_frozen_or_drv_stopped(txq)) {
 		rc = netdev_start_xmit(skb, dev, txq, 0);
 		if (dev_xmit_complete(rc))
 			free_skb = false;
@@ -4883,6 +4887,7 @@ void generic_xdp_tx(struct sk_buff *skb, struct bpf_prog *xdp_prog)
 	HARD_TX_UNLOCK(dev, txq);
 	if (free_skb) {
 		trace_xdp_exception(dev, xdp_prog, XDP_TX);
+		dev_core_stats_tx_dropped_inc(dev);
 		kfree_skb(skb);
 	}
 }
@@ -4923,7 +4928,7 @@ static int netif_rx_internal(struct sk_buff *skb)
 {
 	int ret;
 
-	net_timestamp_check(netdev_tstamp_prequeue, skb);
+	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 
 	trace_netif_rx(skb);
 
@@ -5276,7 +5281,7 @@ static int __netif_receive_skb_core(struct sk_buff **pskb, bool pfmemalloc,
 	int ret = NET_RX_DROP;
 	__be16 type;
 
-	net_timestamp_check(!netdev_tstamp_prequeue, skb);
+	net_timestamp_check(!READ_ONCE(netdev_tstamp_prequeue), skb);
 
 	trace_netif_receive_skb(skb);
 
@@ -5659,7 +5664,7 @@ static int netif_receive_skb_internal(struct sk_buff *skb)
 {
 	int ret;
 
-	net_timestamp_check(netdev_tstamp_prequeue, skb);
+	net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 
 	if (skb_defer_rx_timestamp(skb))
 		return NET_RX_SUCCESS;
@@ -5689,7 +5694,7 @@ void netif_receive_skb_list_internal(struct list_head *head)
 
 	INIT_LIST_HEAD(&sublist);
 	list_for_each_entry_safe(skb, next, head, list) {
-		net_timestamp_check(netdev_tstamp_prequeue, skb);
+		net_timestamp_check(READ_ONCE(netdev_tstamp_prequeue), skb);
 		skb_list_del_init(skb);
 		if (!skb_defer_rx_timestamp(skb))
 			list_add_tail(&skb->list, &sublist);
@@ -5913,7 +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;
 
@@ -6380,6 +6385,7 @@ void netif_napi_add_weight(struct net_device *dev, struct napi_struct *napi,
 	set_bit(NAPI_STATE_NPSVC, &napi->state);
 	list_add_rcu(&napi->dev_list, &dev->napi_list);
 	napi_hash_add(napi);
+	napi_get_frags_check(napi);
 	/* Create kthread for this napi if dev->threaded is set.
 	 * Clear dev->threaded if kthread creation failed so that
 	 * threaded mode will not be enabled in napi_enable().
@@ -6642,8 +6648,8 @@ static __latent_entropy void net_rx_action(struct softirq_action *h)
 {
 	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
 	unsigned long time_limit = jiffies +
-		usecs_to_jiffies(netdev_budget_usecs);
-	int budget = netdev_budget;
+		usecs_to_jiffies(READ_ONCE(netdev_budget_usecs));
+	int budget = READ_ONCE(netdev_budget);
 	LIST_HEAD(list);
 	LIST_HEAD(repoll);
 
@@ -7465,7 +7471,7 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 	adj->ref_nr = 1;
 	adj->private = private;
 	adj->ignore = false;
-	dev_hold_track(adj_dev, &adj->dev_tracker, GFP_KERNEL);
+	netdev_hold(adj_dev, &adj->dev_tracker, GFP_KERNEL);
 
 	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
 		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
@@ -7494,7 +7500,7 @@ remove_symlinks:
 	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
 		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
 free_adj:
-	dev_put_track(adj_dev, &adj->dev_tracker);
+	netdev_put(adj_dev, &adj->dev_tracker);
 	kfree(adj);
 
 	return ret;
@@ -7536,7 +7542,7 @@ static void __netdev_adjacent_dev_remove(struct net_device *dev,
 	list_del_rcu(&adj->list);
 	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
 		 adj_dev->name, dev->name, adj_dev->name);
-	dev_put_track(adj_dev, &adj->dev_tracker);
+	netdev_put(adj_dev, &adj->dev_tracker);
 	kfree_rcu(adj, rcu);
 }
 
@@ -10064,7 +10070,7 @@ int register_netdevice(struct net_device *dev)
 
 	dev_init_scheduler(dev);
 
-	dev_hold_track(dev, &dev->dev_registered_tracker, GFP_KERNEL);
+	netdev_hold(dev, &dev->dev_registered_tracker, GFP_KERNEL);
 	list_netdevice(dev);
 
 	add_device_randomness(dev->dev_addr, dev->addr_len);
@@ -10261,7 +10267,7 @@ static struct net_device *netdev_wait_allrefs_any(struct list_head *list)
 				return dev;
 
 		if (time_after(jiffies, warning_time +
-			       netdev_unregister_timeout_secs * HZ)) {
+			       READ_ONCE(netdev_unregister_timeout_secs) * HZ)) {
 			list_for_each_entry(dev, list, todo_list) {
 				pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
 					 dev->name, netdev_refcnt_read(dev));
@@ -10347,9 +10353,7 @@ void netdev_run_todo(void)
 		BUG_ON(!list_empty(&dev->ptype_specific));
 		WARN_ON(rcu_access_pointer(dev->ip_ptr));
 		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
-#if IS_ENABLED(CONFIG_DECNET)
-		WARN_ON(dev->dn_ptr);
-#endif
+
 		if (dev->priv_destructor)
 			dev->priv_destructor(dev);
 		if (dev->needs_free_netdev)
@@ -10463,23 +10467,23 @@ void dev_fetch_sw_netstats(struct rtnl_link_stats64 *s,
 	int cpu;
 
 	for_each_possible_cpu(cpu) {
+		u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
 		const struct pcpu_sw_netstats *stats;
-		struct pcpu_sw_netstats tmp;
 		unsigned int start;
 
 		stats = per_cpu_ptr(netstats, cpu);
 		do {
 			start = u64_stats_fetch_begin_irq(&stats->syncp);
-			tmp.rx_packets = stats->rx_packets;
-			tmp.rx_bytes   = stats->rx_bytes;
-			tmp.tx_packets = stats->tx_packets;
-			tmp.tx_bytes   = stats->tx_bytes;
+			rx_packets = u64_stats_read(&stats->rx_packets);
+			rx_bytes   = u64_stats_read(&stats->rx_bytes);
+			tx_packets = u64_stats_read(&stats->tx_packets);
+			tx_bytes   = u64_stats_read(&stats->tx_bytes);
 		} while (u64_stats_fetch_retry_irq(&stats->syncp, start));
 
-		s->rx_packets += tmp.rx_packets;
-		s->rx_bytes   += tmp.rx_bytes;
-		s->tx_packets += tmp.tx_packets;
-		s->tx_bytes   += tmp.tx_bytes;
+		s->rx_packets += rx_packets;
+		s->rx_bytes   += rx_bytes;
+		s->tx_packets += tx_packets;
+		s->tx_bytes   += tx_bytes;
 	}
 }
 EXPORT_SYMBOL_GPL(dev_fetch_sw_netstats);
@@ -10873,7 +10877,7 @@ void unregister_netdevice_many(struct list_head *head)
 	synchronize_net();
 
 	list_for_each_entry(dev, head, unreg_list) {
-		dev_put_track(dev, &dev->dev_registered_tracker);
+		netdev_put(dev, &dev->dev_registered_tracker);
 		net_set_todo(dev);
 	}