[PATCH] net: pasemi: fix an use-after-free in pasemi_mac_phy_init()

From: Wen Yang
Date: Sat Jul 06 2019 - 00:25:38 EST


The phy_dn variable is still being used in of_phy_connect() after the
of_node_put() call, which may result in use-after-free.

Fixes: 1dd2d06c0459 ("net: Rework pasemi_mac driver to use of_mdio infrastructure")
Signed-off-by: Wen Yang <wen.yang99@xxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/net/ethernet/pasemi/pasemi_mac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/pasemi/pasemi_mac.c b/drivers/net/ethernet/pasemi/pasemi_mac.c
index bf5a7bc..be66601 100644
--- a/drivers/net/ethernet/pasemi/pasemi_mac.c
+++ b/drivers/net/ethernet/pasemi/pasemi_mac.c
@@ -1042,7 +1042,6 @@ static int pasemi_mac_phy_init(struct net_device *dev)

dn = pci_device_to_OF_node(mac->pdev);
phy_dn = of_parse_phandle(dn, "phy-handle", 0);
- of_node_put(phy_dn);

mac->link = 0;
mac->speed = 0;
@@ -1051,6 +1050,7 @@ static int pasemi_mac_phy_init(struct net_device *dev)
phydev = of_phy_connect(dev, phy_dn, &pasemi_adjust_link, 0,
PHY_INTERFACE_MODE_SGMII);

+ of_node_put(phy_dn);
if (!phydev) {
printk(KERN_ERR "%s: Could not attach to phy\n", dev->name);
return -ENODEV;
--
2.9.5