From: Florian Fainelli <f.fainelli@xxxxxxxxx>
[ Upstream commit c2b727df7caa33876e7066bde090f40001b6d643 ]
If we have unbound the PHY driver prior to calling phy_detach() (often
via phy_disconnect()) then we can cause a NULL pointer de-reference
accessing the driver owner member. The steps to reproduce are:
echo unimac-mdio-0:01 > /sys/class/net/eth0/phydev/driver/unbind
ip link set eth0 down
Fixes: cafe8df8b9bc ("net: phy: Fix lack of reference count on PHY driver")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/phy_device.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -1013,7 +1013,8 @@ void phy_detach(struct phy_device *phyde
phydev->attached_dev = NULL;
phy_suspend(phydev);
- module_put(phydev->mdio.dev.driver->owner);
+ if (phydev->mdio.dev.driver)
+ module_put(phydev->mdio.dev.driver->owner);
/* If the device had no specific driver before (i.e. - it
* was using the generic driver), we unbind the device
