net: phy: Fix PHY module checks and NULL deref in phy_attach_direct()
[ Upstream commit 6d9f66ac7fec2a6ccd649e5909806dfe36f1fc25 ]
The Generic PHY drivers gets assigned after we checked that the current
PHY driver is NULL, so we need to check a few things before we can
safely dereference d->driver. This would be causing a NULL deference to
occur when a system binds to the Generic PHY driver. Update
phy_attach_direct() to do the following:
- grab the driver module reference after we have assigned the Generic
PHY drivers accordingly, and remember we came from the generic PHY
path
- update the error path to clean up the module reference in case the
Generic PHY probe function fails
- split the error path involving phy_detacht() to avoid double free/put
since phy_detach() does all the clean up
- finally, have phy_detach() drop the module reference count before we
call device_release_driver() for the Generic PHY driver case
Fixes: cafe8df8b9bc ("net: phy: Fix lack of reference count on PHY driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed