diff options
| author | Lukas Wunner <lukas@wunner.de> | 2022-05-12 10:42:01 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-05-13 11:35:46 +0100 |
| commit | d1408f6b4dd78fb1b9e26bcf64477984e5f85409 (patch) | |
| tree | bd12b3a718093e7213135f486678530eb5bd1a9b /drivers/net/usb/usbnet.c | |
| parent | 7b8b82224c26863d9b6c67f6cc6044bc24044e44 (diff) | |
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/usbnet.c')
| -rw-r--r-- | drivers/net/usb/usbnet.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c index 9a6450f796dc..36b24ec11650 100644 --- a/drivers/net/usb/usbnet.c +++ b/drivers/net/usb/usbnet.c @@ -1616,9 +1616,6 @@ void usbnet_disconnect (struct usb_interface *intf) xdev->bus->bus_name, xdev->devpath, dev->driver_info->description); - if (dev->driver_info->unbind) - dev->driver_info->unbind(dev, intf); - net = dev->net; unregister_netdev (net); @@ -1626,6 +1623,9 @@ void usbnet_disconnect (struct usb_interface *intf) usb_scuttle_anchored_urbs(&dev->deferred); + if (dev->driver_info->unbind) + dev->driver_info->unbind(dev, intf); + usb_kill_urb(dev->interrupt); usb_free_urb(dev->interrupt); kfree(dev->padding_pkt); |