From cbda1b16687580d5beee38273f6241ae3725960c Mon Sep 17 00:00:00 2001 From: =?utf8?q?Marek=20Beh=C3=BAn?= Date: Wed, 19 Jan 2022 17:27:48 +0100 Subject: [PATCH] phylib: fix potential use-after-free MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Commit bafbdd527d56 ("phylib: Add device reset GPIO support") added call to phy_device_reset(phydev) after the put_device() call in phy_detach(). The comment before the put_device() call says that the phydev might go away with put_device(). Fix potential use-after-free by calling phy_device_reset() before put_device(). Fixes: bafbdd527d56 ("phylib: Add device reset GPIO support") Signed-off-by: Marek Behún Reviewed-by: Andrew Lunn Link: https://lore.kernel.org/r/20220119162748.32418-1-kabel@kernel.org Signed-off-by: Jakub Kicinski --- drivers/net/phy/phy_device.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c index 74d8e1d..ce0bb59 100644 --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1746,6 +1746,9 @@ void phy_detach(struct phy_device *phydev) phy_driver_is_genphy_10g(phydev)) device_release_driver(&phydev->mdio.dev); + /* Assert the reset signal */ + phy_device_reset(phydev, 1); + /* * The phydev might go away on the put_device() below, so avoid * a use-after-free bug by reading the underlying bus first. @@ -1757,9 +1760,6 @@ void phy_detach(struct phy_device *phydev) ndev_owner = dev->dev.parent->driver->owner; if (ndev_owner != bus->owner) module_put(bus->owner); - - /* Assert the reset signal */ - phy_device_reset(phydev, 1); } EXPORT_SYMBOL(phy_detach); -- 2.7.4