1 files changed, 22 insertions, 17 deletions

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index a09d507c5b03..946caefdd959 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -34,10 +34,10 @@ static const char fmt_dec[] = "%d\n";
 static const char fmt_ulong[] = "%lu\n";
 static const char fmt_u64[] = "%llu\n";
 
-/* Caller holds RTNL or dev_base_lock */
+/* Caller holds RTNL or RCU */
 static inline int dev_isalive(const struct net_device *dev)
 {
-	return dev->reg_state <= NETREG_REGISTERED;
+	return READ_ONCE(dev->reg_state) <= NETREG_REGISTERED;
 }
 
 /* use same locking rules as GIF* ioctl's */
@@ -48,10 +48,10 @@ static ssize_t netdev_show(const struct device *dev,
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 	if (dev_isalive(ndev))
 		ret = (*format)(ndev, buf);
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 
 	return ret;
 }
@@ -60,7 +60,7 @@ static ssize_t netdev_show(const struct device *dev,
 #define NETDEVICE_SHOW(field, format_string)				\
 static ssize_t format_##field(const struct net_device *dev, char *buf)	\
 {									\
-	return sysfs_emit(buf, format_string, dev->field);		\
+	return sysfs_emit(buf, format_string, READ_ONCE(dev->field));		\
 }									\
 static ssize_t field##_show(struct device *dev,				\
 			    struct device_attribute *attr, char *buf)	\
@@ -125,7 +125,7 @@ static DEVICE_ATTR_RO(iflink);
 
 static ssize_t format_name_assign_type(const struct net_device *dev, char *buf)
 {
-	return sysfs_emit(buf, fmt_dec, dev->name_assign_type);
+	return sysfs_emit(buf, fmt_dec, READ_ONCE(dev->name_assign_type));
 }
 
 static ssize_t name_assign_type_show(struct device *dev,
@@ -135,24 +135,28 @@ static ssize_t name_assign_type_show(struct device *dev,
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	if (ndev->name_assign_type != NET_NAME_UNKNOWN)
+	if (READ_ONCE(ndev->name_assign_type) != NET_NAME_UNKNOWN)
 		ret = netdev_show(dev, attr, buf, format_name_assign_type);
 
 	return ret;
 }
 static DEVICE_ATTR_RO(name_assign_type);
 
-/* use same locking rules as GIFHWADDR ioctl's */
+/* use same locking rules as GIFHWADDR ioctl's (dev_get_mac_address()) */
 static ssize_t address_show(struct device *dev, struct device_attribute *attr,
 			    char *buf)
 {
 	struct net_device *ndev = to_net_dev(dev);
 	ssize_t ret = -EINVAL;
 
-	read_lock(&dev_base_lock);
+	down_read(&dev_addr_sem);
+
+	rcu_read_lock();
 	if (dev_isalive(ndev))
 		ret = sysfs_format_mac(buf, ndev->dev_addr, ndev->addr_len);
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
+
+	up_read(&dev_addr_sem);
 	return ret;
 }
 static DEVICE_ATTR_RO(address);
@@ -161,10 +165,13 @@ static ssize_t broadcast_show(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
 	struct net_device *ndev = to_net_dev(dev);
+	int ret = -EINVAL;
 
+	rcu_read_lock();
 	if (dev_isalive(ndev))
-		return sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
-	return -EINVAL;
+		ret = sysfs_format_mac(buf, ndev->broadcast, ndev->addr_len);
+	rcu_read_unlock();
+	return ret;
 }
 static DEVICE_ATTR_RO(broadcast);
 
@@ -318,11 +325,9 @@ static ssize_t operstate_show(struct device *dev,
 	const struct net_device *netdev = to_net_dev(dev);
 	unsigned char operstate;
 
-	read_lock(&dev_base_lock);
-	operstate = netdev->operstate;
+	operstate = READ_ONCE(netdev->operstate);
 	if (!netif_running(netdev))
 		operstate = IF_OPER_DOWN;
-	read_unlock(&dev_base_lock);
 
 	if (operstate >= ARRAY_SIZE(operstates))
 		return -EINVAL; /* should not happen */
@@ -680,14 +685,14 @@ static ssize_t netstat_show(const struct device *d,
 	WARN_ON(offset > sizeof(struct rtnl_link_stats64) ||
 		offset % sizeof(u64) != 0);
 
-	read_lock(&dev_base_lock);
+	rcu_read_lock();
 	if (dev_isalive(dev)) {
 		struct rtnl_link_stats64 temp;
 		const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
 
 		ret = sysfs_emit(buf, fmt_u64, *(u64 *)(((u8 *)stats) + offset));
 	}
-	read_unlock(&dev_base_lock);
+	rcu_read_unlock();
 	return ret;
 }