@@ -3275,6 +3275,8 @@ static inline struct net_device *first_net_device_rcu(struct net *net)
}
int netdev_boot_setup_check(struct net_device *dev);
+struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type,
+ const char *hwaddr);
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
const char *hwaddr);
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type);
@@ -1121,6 +1121,12 @@ int netdev_get_name(struct net *net, char *name, int ifindex)
return ret;
}
+static bool dev_comp_addr(struct net_device *dev, unsigned short type,
+ const char *ha)
+{
+ return dev->type == type && !memcmp(dev->dev_addr, ha, dev->addr_len);
+}
+
/**
* dev_getbyhwaddr_rcu - find a device by its hardware address
* @net: the applicable net namespace
@@ -1129,7 +1135,7 @@ int netdev_get_name(struct net *net, char *name, int ifindex)
*
* Search for an interface by MAC address. Returns NULL if the device
* is not found or a pointer to the device.
- * The caller must hold RCU or RTNL.
+ * The caller must hold RCU.
* The returned device has not had its ref count increased
* and the caller must therefore be careful about locking
*
@@ -1141,14 +1147,39 @@ struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
struct net_device *dev;
for_each_netdev_rcu(net, dev)
- if (dev->type == type &&
- !memcmp(dev->dev_addr, ha, dev->addr_len))
+ if (dev_comp_addr(dev, type, ha))
return dev;
return NULL;
}
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
+/**
+ * dev_getbyhwaddr - find a device by its hardware address
+ * @net: the applicable net namespace
+ * @type: media type of device
+ * @ha: hardware address
+ *
+ * Similar to dev_getbyhwaddr_rcu(), but the owner needs to hold
+ * rtnl_lock.
+ *
+ * Context: rtnl_lock() must be held.
+ * Return: pointer to the net_device, or NULL if not found
+ */
+struct net_device *dev_getbyhwaddr(struct net *net, unsigned short type,
+ const char *ha)
+{
+ struct net_device *dev;
+
+ ASSERT_RTNL();
+ for_each_netdev(net, dev)
+ if (dev_comp_addr(dev, type, ha))
+ return dev;
+
+ return NULL;
+}
+EXPORT_SYMBOL(dev_getbyhwaddr);
+
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
{
struct net_device *dev, *ret = NULL;
Add dedicated helper for finding devices by hardware address when holding rtnl_lock, similar to existing dev_getbyhwaddr_rcu(). This prevents PROVE_LOCKING warnings when rtnl_lock is held but RCU read lock is not. Extract common address comparison logic into dev_comp_addr(). The context about this change could be found in the following discussion: Link: https://lore.kernel.org/all/20250206-scarlet-ermine-of-improvement-1fcac5@leitao/ Cc: kuniyu@amazon.com Cc: ushankar@purestorage.com Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Breno Leitao <leitao@debian.org> --- include/linux/netdevice.h | 2 ++ net/core/dev.c | 37 ++++++++++++++++++++++++++++++++++--- 2 files changed, 36 insertions(+), 3 deletions(-)