diff options
author | Lukas Wunner <lukas@wunner.de> | 2022-05-12 11:42:01 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2022-05-13 13:35:46 +0300 |
commit | d1408f6b4dd78fb1b9e26bcf64477984e5f85409 (patch) | |
tree | bd12b3a718093e7213135f486678530eb5bd1a9b /drivers/net/usb/asix_devices.c | |
parent | 7b8b82224c26863d9b6c67f6cc6044bc24044e44 (diff) | |
download | linux-d1408f6b4dd78fb1b9e26bcf64477984e5f85409.tar.xz |
usbnet: Run unregister_netdev() before unbind() again
Commit 2c9d6c2b871d ("usbnet: run unbind() before unregister_netdev()")
sought to fix a use-after-free on disconnect of USB Ethernet adapters.
It turns out that a different fix is necessary to address the issue:
https://lore.kernel.org/netdev/18b3541e5372bc9b9fc733d422f4e698c089077c.1650177997.git.lukas@wunner.de/
So the commit was not necessary.
The commit made binding and unbinding of USB Ethernet asymmetrical:
Before, usbnet_probe() first invoked the ->bind() callback and then
register_netdev(). usbnet_disconnect() mirrored that by first invoking
unregister_netdev() and then ->unbind().
Since the commit, the order in usbnet_disconnect() is reversed and no
longer mirrors usbnet_probe().
One consequence is that a PHY disconnected (and stopped) in ->unbind()
is afterwards stopped once more by unregister_netdev() as it closes the
netdev before unregistering. That necessitates a contortion in ->stop()
because the PHY may only be stopped if it hasn't already been
disconnected.
Reverting the commit allows making the call to phy_stop() unconditional
in ->stop().
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> # LAN9514/9512/9500
Tested-by: Ferry Toth <fntoth@gmail.com> # LAN9514
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Acked-by: Oliver Neukum <oneukum@suse.com>
Cc: Martyn Welch <martyn.welch@collabora.com>
Cc: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/usb/asix_devices.c')
-rw-r--r-- | drivers/net/usb/asix_devices.c | 6 |
1 files changed, 1 insertions, 5 deletions
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c index 38e47a93fb83..5b5eb630c4b7 100644 --- a/drivers/net/usb/asix_devices.c +++ b/drivers/net/usb/asix_devices.c @@ -795,11 +795,7 @@ static int ax88772_stop(struct usbnet *dev) { struct asix_common_private *priv = dev->driver_priv; - /* On unplugged USB, we will get MDIO communication errors and the - * PHY will be set in to PHY_HALTED state. - */ - if (priv->phydev->state != PHY_HALTED) - phy_stop(priv->phydev); + phy_stop(priv->phydev); return 0; } |