Merge tag 'v4.4.177' into toradex_vf_4.4-nextColibri-VF_LXDE-Image_2.8b6.183-20190331

This is the 4.4.177 stable release

4 files changed, 21 insertions, 15 deletions

diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 2fdebabbfacd..2772f6a13fcb 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -654,15 +654,22 @@ static int ax25_setsockopt(struct socket *sock, int level, int optname,
 			break;
 		}
 
-		dev = dev_get_by_name(&init_net, devname);
+		rtnl_lock();
+		dev = __dev_get_by_name(&init_net, devname);
 		if (!dev) {
+			rtnl_unlock();
 			res = -ENODEV;
 			break;
 		}
 
 		ax25->ax25_dev = ax25_dev_ax25dev(dev);
+		if (!ax25->ax25_dev) {
+			rtnl_unlock();
+			res = -ENODEV;
+			break;
+		}
 		ax25_fillin_cb(ax25, ax25->ax25_dev);
-		dev_put(dev);
+		rtnl_unlock();
 		break;
 
 	default:
diff --git a/net/ax25/ax25_dev.c b/net/ax25/ax25_dev.c
index 3d106767b272..5faca5db6385 100644
--- a/net/ax25/ax25_dev.c
+++ b/net/ax25/ax25_dev.c
@@ -116,6 +116,7 @@ void ax25_dev_device_down(struct net_device *dev)
 	if ((s = ax25_dev_list) == ax25_dev) {
 		ax25_dev_list = s->next;
 		spin_unlock_bh(&ax25_dev_lock);
+		dev->ax25_ptr = NULL;
 		dev_put(dev);
 		kfree(ax25_dev);
 		return;
@@ -125,6 +126,7 @@ void ax25_dev_device_down(struct net_device *dev)
 		if (s->next == ax25_dev) {
 			s->next = ax25_dev->next;
 			spin_unlock_bh(&ax25_dev_lock);
+			dev->ax25_ptr = NULL;
 			dev_put(dev);
 			kfree(ax25_dev);
 			return;
diff --git a/net/ax25/ax25_ip.c b/net/ax25/ax25_ip.c
index 2fa3be965101..cd9a24e5b97a 100644
--- a/net/ax25/ax25_ip.c
+++ b/net/ax25/ax25_ip.c
@@ -114,6 +114,7 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb)
 	dst = (ax25_address *)(bp + 1);
 	src = (ax25_address *)(bp + 8);
 
+	ax25_route_lock_use();
 	route = ax25_get_route(dst, NULL);
 	if (route) {
 		digipeat = route->digipeat;
@@ -206,9 +207,8 @@ netdev_tx_t ax25_ip_xmit(struct sk_buff *skb)
 	ax25_queue_xmit(skb, dev);
 
 put:
-	if (route)
-		ax25_put_route(route);
 
+	ax25_route_lock_unuse();
 	return NETDEV_TX_OK;
 }
 
diff --git a/net/ax25/ax25_route.c b/net/ax25/ax25_route.c
index d39097737e38..149f82bd83fd 100644
--- a/net/ax25/ax25_route.c
+++ b/net/ax25/ax25_route.c
@@ -40,7 +40,7 @@
 #include <linux/export.h>
 
 static ax25_route *ax25_route_list;
-static DEFINE_RWLOCK(ax25_route_lock);
+DEFINE_RWLOCK(ax25_route_lock);
 
 void ax25_rt_device_down(struct net_device *dev)
 {
@@ -349,6 +349,7 @@ const struct file_operations ax25_route_fops = {
  *	Find AX.25 route
  *
  *	Only routes with a reference count of zero can be destroyed.
+ *	Must be called with ax25_route_lock read locked.
  */
 ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev)
 {
@@ -356,7 +357,6 @@ ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev)
 	ax25_route *ax25_def_rt = NULL;
 	ax25_route *ax25_rt;
 
-	read_lock(&ax25_route_lock);
 	/*
 	 *	Bind to the physical interface we heard them on, or the default
 	 *	route if none is found;
@@ -379,11 +379,6 @@ ax25_route *ax25_get_route(ax25_address *addr, struct net_device *dev)
 	if (ax25_spe_rt != NULL)
 		ax25_rt = ax25_spe_rt;
 
-	if (ax25_rt != NULL)
-		ax25_hold_route(ax25_rt);
-
-	read_unlock(&ax25_route_lock);
-
 	return ax25_rt;
 }
 
@@ -414,9 +409,12 @@ int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr)
 	ax25_route *ax25_rt;
 	int err = 0;
 
-	if ((ax25_rt = ax25_get_route(addr, NULL)) == NULL)
+	ax25_route_lock_use();
+	ax25_rt = ax25_get_route(addr, NULL);
+	if (!ax25_rt) {
+		ax25_route_lock_unuse();
 		return -EHOSTUNREACH;
-
+	}
 	if ((ax25->ax25_dev = ax25_dev_ax25dev(ax25_rt->dev)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto put;
@@ -451,8 +449,7 @@ int ax25_rt_autobind(ax25_cb *ax25, ax25_address *addr)
 	}
 
 put:
-	ax25_put_route(ax25_rt);
-
+	ax25_route_lock_unuse();
 	return err;
 }