Commit b2309a71 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

net: add dev->dev_registered_tracker 



Convert one dev_hold()/dev_put() pair in register_netdevice()
and unregister_netdevice_many() to dev_hold_track()
and dev_put_track().

This would allow to detect a rogue dev_put() a bit earlier.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220207184107.1401096-1-eric.dumazet@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 99f5a5f2

include/linux/netdevice.h

+3 −0
Original line number Diff line number Diff line
@@ -1948,6 +1948,8 @@ enum netdev_ml_priv_type { 
 *	@dev_addr_shadow:	Copy of @dev_addr to catch direct writes.

 *	@linkwatch_dev_tracker:	refcount tracker used by linkwatch.

 *	@watchdog_dev_tracker:	refcount tracker used by watchdog.

 *	@dev_registered_tracker:	tracker for reference held while

 *					registered

 *

 *	FIXME: cleanup struct net_device such that network protocol info

 *	moves out.
@@ -2282,6 +2284,7 @@ struct net_device { 
	u8 dev_addr_shadow[MAX_ADDR_LEN];

	netdevice_tracker	linkwatch_dev_tracker;

	netdevice_tracker	watchdog_dev_tracker;

	netdevice_tracker	dev_registered_tracker;

};

#define to_net_dev(d) container_of(d, struct net_device, dev)

net/core/dev.c

+4 −2
Original line number Diff line number Diff line
@@ -9683,8 +9683,10 @@ int register_netdevice(struct net_device *dev) 
	linkwatch_init_dev(dev);



	dev_init_scheduler(dev);

	dev_hold(dev);



	dev_hold_track(dev, &dev->dev_registered_tracker, GFP_KERNEL);

	list_netdevice(dev);



	add_device_randomness(dev->dev_addr, dev->addr_len);



	/* If the device has permanent device address, driver should
@@ -10449,7 +10451,7 @@ void unregister_netdevice_many(struct list_head *head) 
	synchronize_net();



	list_for_each_entry(dev, head, unreg_list) {

		dev_put(dev);

		dev_put_track(dev, &dev->dev_registered_tracker);

		net_set_todo(dev);

	}