From 0e0daf6ac3be70608569262246f6dc33cb3f45fe Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Thu, 30 Jan 2020 18:44:50 +0100 Subject: [PATCH] net: mdio: of: fix potential NULL pointer derefernce of_find_mii_timestamper() returns NULL if no timestamper is found. Therefore, guard the unregister_mii_timestamper() calls. Fixes: 1dca22b18421 ("net: mdio: of: Register discovered MII time stampers.") Signed-off-by: Michael Walle Acked-by: Richard Cochran Signed-off-by: Jakub Kicinski --- drivers/of/of_mdio.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/of/of_mdio.c b/drivers/of/of_mdio.c index f5c2a5487761..db0ed5879803 100644 --- a/drivers/of/of_mdio.c +++ b/drivers/of/of_mdio.c @@ -81,13 +81,15 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, else phy = get_phy_device(mdio, addr, is_c45); if (IS_ERR(phy)) { - unregister_mii_timestamper(mii_ts); + if (mii_ts) + unregister_mii_timestamper(mii_ts); return PTR_ERR(phy); } rc = of_irq_get(child, 0); if (rc == -EPROBE_DEFER) { - unregister_mii_timestamper(mii_ts); + if (mii_ts) + unregister_mii_timestamper(mii_ts); phy_device_free(phy); return rc; } @@ -116,7 +118,8 @@ static int of_mdiobus_register_phy(struct mii_bus *mdio, * register it */ rc = phy_device_register(phy); if (rc) { - unregister_mii_timestamper(mii_ts); + if (mii_ts) + unregister_mii_timestamper(mii_ts); phy_device_free(phy); of_node_put(child); return rc; -- 2.34.1