From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:52596 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751662AbdFOK1f (ORCPT ); Thu, 15 Jun 2017 06:27:35 -0400 Subject: Patch "net: phy: Fix PHY module checks and NULL deref in phy_attach_direct()" has been added to the 4.9-stable tree To: f.fainelli@gmail.com, alexander.levin@verizon.com, davem@davemloft.net, gregkh@linuxfoundation.org Cc: , From: Date: Thu, 15 Jun 2017 12:27:18 +0200 Message-ID: <1497522438162125@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled net: phy: Fix PHY module checks and NULL deref in phy_attach_direct() to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-phy-fix-phy-module-checks-and-null-deref-in-phy_attach_direct.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From foo@baz Thu Jun 15 12:25:36 CEST 2017 From: Florian Fainelli Date: Wed, 8 Feb 2017 19:05:26 -0800 Subject: net: phy: Fix PHY module checks and NULL deref in phy_attach_direct() From: Florian Fainelli [ 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 Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/phy_device.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-) --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -860,6 +860,7 @@ int phy_attach_direct(struct net_device struct module *ndev_owner = dev->dev.parent->driver->owner; struct mii_bus *bus = phydev->mdio.bus; struct device *d = &phydev->mdio.dev; + bool using_genphy = false; int err; /* For Ethernet device drivers that register their own MDIO bus, we @@ -872,11 +873,6 @@ int phy_attach_direct(struct net_device return -EIO; } - if (!try_module_get(d->driver->owner)) { - dev_err(&dev->dev, "failed to get the device driver module\n"); - return -EIO; - } - get_device(d); /* Assume that if there is no driver, that it doesn't @@ -890,12 +886,22 @@ int phy_attach_direct(struct net_device d->driver = &genphy_driver[GENPHY_DRV_1G].mdiodrv.driver; + using_genphy = true; + } + + if (!try_module_get(d->driver->owner)) { + dev_err(&dev->dev, "failed to get the device driver module\n"); + err = -EIO; + goto error_put_device; + } + + if (using_genphy) { err = d->driver->probe(d); if (err >= 0) err = device_bind_driver(d); if (err) - goto error; + goto error_module_put; } if (phydev->attached_dev) { @@ -931,8 +937,14 @@ int phy_attach_direct(struct net_device return err; error: - put_device(d); + /* phy_detach() does all of the cleanup below */ + phy_detach(phydev); + return err; + +error_module_put: module_put(d->driver->owner); +error_put_device: + put_device(d); if (ndev_owner != bus->owner) module_put(bus->owner); return err; @@ -993,6 +1005,8 @@ void phy_detach(struct phy_device *phyde phydev->attached_dev = NULL; phy_suspend(phydev); + 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 * from the generic driver so that there's a chance a @@ -1013,7 +1027,6 @@ void phy_detach(struct phy_device *phyde bus = phydev->mdio.bus; put_device(&phydev->mdio.dev); - module_put(phydev->mdio.dev.driver->owner); if (ndev_owner != bus->owner) module_put(bus->owner); } Patches currently in stable-queue which might be from f.fainelli@gmail.com are queue-4.9/net-phy-fix-lack-of-reference-count-on-phy-driver.patch queue-4.9/net-phy-fix-phy-module-checks-and-null-deref-in-phy_attach_direct.patch