From: Eric Dumazet <edumazet@google.com>
Date: Sun, 5 Dec 2021 04:22:00 +0000 (-0800)
Subject: net: add net device refcount tracker to ethtool_phys_id()
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5ae2195088d06adfd20eab98ecc9db80ef2eb6b2;p=linux.git

net: add net device refcount tracker to ethtool_phys_id()

This helper might hold a netdev reference for a long time,
lets add reference tracking.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index fa8aa5ec19ba1..9a113d8935212 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1989,6 +1989,7 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr)
 	struct ethtool_value id;
 	static bool busy;
 	const struct ethtool_ops *ops = dev->ethtool_ops;
+	netdevice_tracker dev_tracker;
 	int rc;
 
 	if (!ops->set_phys_id)
@@ -2008,7 +2009,7 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr)
 	 * removal of the device.
 	 */
 	busy = true;
-	dev_hold(dev);
+	dev_hold_track(dev, &dev_tracker, GFP_KERNEL);
 	rtnl_unlock();
 
 	if (rc == 0) {
@@ -2032,7 +2033,7 @@ static int ethtool_phys_id(struct net_device *dev, void __user *useraddr)
 	}
 
 	rtnl_lock();
-	dev_put(dev);
+	dev_put_track(dev, &dev_tracker);
 	busy = false;
 
 	(void) ops->set_phys_id(dev, ETHTOOL_ID_INACTIVE);