1 files changed, 27 insertions, 10 deletions

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index e9ca1c088d0b..abae165dcca5 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -596,18 +596,22 @@ static u16 tun_automq_select_queue(struct tun_struct *tun, struct sk_buff *skb)
 static u16 tun_ebpf_select_queue(struct tun_struct *tun, struct sk_buff *skb)
 {
 	struct tun_prog *prog;
+	u32 numqueues;
 	u16 ret = 0;
 
+	numqueues = READ_ONCE(tun->numqueues);
+	if (!numqueues)
+		return 0;
+
 	prog = rcu_dereference(tun->steering_prog);
 	if (prog)
 		ret = bpf_prog_run_clear_cb(prog->prog, skb);
 
-	return ret % tun->numqueues;
+	return ret % numqueues;
 }
 
 static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb,
-			    struct net_device *sb_dev,
-			    select_queue_fallback_t fallback)
+			    struct net_device *sb_dev)
 {
 	struct tun_struct *tun = netdev_priv(dev);
 	u16 ret;
@@ -700,6 +704,8 @@ static void __tun_detach(struct tun_file *tfile, bool clean)
 				   tun->tfiles[tun->numqueues - 1]);
 		ntfile = rtnl_dereference(tun->tfiles[index]);
 		ntfile->queue_index = index;
+		rcu_assign_pointer(tun->tfiles[tun->numqueues - 1],
+				   NULL);
 
 		--tun->numqueues;
 		if (clean) {
@@ -1043,7 +1049,7 @@ static int tun_net_close(struct net_device *dev)
 static void tun_automq_xmit(struct tun_struct *tun, struct sk_buff *skb)
 {
 #ifdef CONFIG_RPS
-	if (tun->numqueues == 1 && static_key_false(&rps_needed)) {
+	if (tun->numqueues == 1 && static_branch_unlikely(&rps_needed)) {
 		/* Select queue was not called for the skbuff, so we extract the
 		 * RPS hash and save it into the flow_table here.
 		 */
@@ -1082,7 +1088,7 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
 	tfile = rcu_dereference(tun->tfiles[txq]);
 
 	/* Drop packet if interface is not attached */
-	if (txq >= tun->numqueues)
+	if (!tfile)
 		goto drop;
 
 	if (!rcu_dereference(tun->steering_prog))
@@ -1305,6 +1311,7 @@ static int tun_xdp_xmit(struct net_device *dev, int n,
 
 	rcu_read_lock();
 
+resample:
 	numqueues = READ_ONCE(tun->numqueues);
 	if (!numqueues) {
 		rcu_read_unlock();
@@ -1313,6 +1320,8 @@ static int tun_xdp_xmit(struct net_device *dev, int n,
 
 	tfile = rcu_dereference(tun->tfiles[smp_processor_id() %
 					    numqueues]);
+	if (unlikely(!tfile))
+		goto resample;
 
 	spin_lock(&tfile->tx_ring.producer_lock);
 	for (i = 0; i < n; i++) {
@@ -1966,7 +1975,8 @@ drop:
 
 	if (frags) {
 		/* Exercise flow dissector code path. */
-		u32 headlen = eth_get_headlen(skb->data, skb_headlen(skb));
+		u32 headlen = eth_get_headlen(tun->dev, skb->data,
+					      skb_headlen(skb));
 
 		if (unlikely(headlen > skb_headlen(skb))) {
 			this_cpu_inc(tun->pcpu_stats->rx_dropped);
@@ -2873,8 +2883,7 @@ err_free_dev:
 	return err;
 }
 
-static void tun_get_iff(struct net *net, struct tun_struct *tun,
-		       struct ifreq *ifr)
+static void tun_get_iff(struct tun_struct *tun, struct ifreq *ifr)
 {
 	tun_debug(KERN_INFO, tun, "tun_get_iff\n");
 
@@ -3103,10 +3112,11 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 
 	tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %u\n", cmd);
 
+	net = dev_net(tun->dev);
 	ret = 0;
 	switch (cmd) {
 	case TUNGETIFF:
-		tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
+		tun_get_iff(tun, &ifr);
 
 		if (tfile->detached)
 			ifr.ifr_flags |= IFF_DETACH_QUEUE;
@@ -3328,6 +3338,13 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
 		ret = tun_net_change_carrier(tun->dev, (bool)carrier);
 		break;
 
+	case TUNGETDEVNETNS:
+		ret = -EPERM;
+		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+			goto unlock;
+		ret = open_related_ns(&net->ns, get_net_ns);
+		break;
+
 	default:
 		ret = -EINVAL;
 		break;
@@ -3457,7 +3474,7 @@ static void tun_chr_show_fdinfo(struct seq_file *m, struct file *file)
 	rtnl_lock();
 	tun = tun_get(tfile);
 	if (tun)
-		tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
+		tun_get_iff(tun, &ifr);
 	rtnl_unlock();
 
 	if (tun)