From aed13f2e00ce278f039b76e7ac84d419aff48ef6 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 16 Jan 2019 11:23:33 +0100 Subject: [PATCH 1/3] net: dsa: lantiq_gswip: fix use-after-free on failed probe Make sure to disable and deregister the switch on late probe errors to avoid use-after-free when the device-resource-managed switch is freed. Fixes: 14fceff4771e ("net: dsa: Add Lantiq / Intel DSA driver for vrx200") Cc: stable # 4.20 Cc: Hauke Mehrtens Signed-off-by: Johan Hovold Reviewed-by: Andrew Lunn Acked-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/dsa/lantiq_gswip.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c index 693a67f45bef..b06c41c98de9 100644 --- a/drivers/net/dsa/lantiq_gswip.c +++ b/drivers/net/dsa/lantiq_gswip.c @@ -1099,7 +1099,7 @@ static int gswip_probe(struct platform_device *pdev) dev_err(dev, "wrong CPU port defined, HW only supports port: %i", priv->hw_info->cpu_port); err = -EINVAL; - goto mdio_bus; + goto disable_switch; } platform_set_drvdata(pdev, priv); @@ -1109,6 +1109,9 @@ static int gswip_probe(struct platform_device *pdev) (version & GSWIP_VERSION_MOD_MASK) >> GSWIP_VERSION_MOD_SHIFT); return 0; +disable_switch: + gswip_mdio_mask(priv, GSWIP_MDIO_GLOB_ENABLE, 0, GSWIP_MDIO_GLOB); + dsa_unregister_switch(priv->ds); mdio_bus: if (mdio_np) mdiobus_unregister(priv->ds->slave_mii_bus); From c8cbcb0d8bd72d44fad1a5ddc348ac10e0fb1b37 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 16 Jan 2019 11:23:34 +0100 Subject: [PATCH 2/3] net: dsa: lantiq_gswip: fix OF child-node lookups Use the new of_get_compatible_child() helper to look up child nodes to avoid ever matching non-child nodes elsewhere in the tree. Also fix up the related struct device_node leaks. Fixes: 14fceff4771e ("net: dsa: Add Lantiq / Intel DSA driver for vrx200") Cc: stable # 4.20 Cc: Hauke Mehrtens Signed-off-by: Johan Hovold Reviewed-by: Andrew Lunn Acked-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/dsa/lantiq_gswip.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c index b06c41c98de9..5792674dd4e4 100644 --- a/drivers/net/dsa/lantiq_gswip.c +++ b/drivers/net/dsa/lantiq_gswip.c @@ -1069,10 +1069,10 @@ static int gswip_probe(struct platform_device *pdev) version = gswip_switch_r(priv, GSWIP_VERSION); /* bring up the mdio bus */ - gphy_fw_np = of_find_compatible_node(pdev->dev.of_node, NULL, - "lantiq,gphy-fw"); + gphy_fw_np = of_get_compatible_child(dev->of_node, "lantiq,gphy-fw"); if (gphy_fw_np) { err = gswip_gphy_fw_list(priv, gphy_fw_np, version); + of_node_put(gphy_fw_np); if (err) { dev_err(dev, "gphy fw probe failed\n"); return err; @@ -1080,13 +1080,12 @@ static int gswip_probe(struct platform_device *pdev) } /* bring up the mdio bus */ - mdio_np = of_find_compatible_node(pdev->dev.of_node, NULL, - "lantiq,xrx200-mdio"); + mdio_np = of_get_compatible_child(dev->of_node, "lantiq,xrx200-mdio"); if (mdio_np) { err = gswip_mdio(priv, mdio_np); if (err) { dev_err(dev, "mdio probe failed\n"); - goto gphy_fw; + goto put_mdio_node; } } @@ -1115,7 +1114,8 @@ disable_switch: mdio_bus: if (mdio_np) mdiobus_unregister(priv->ds->slave_mii_bus); -gphy_fw: +put_mdio_node: + of_node_put(mdio_np); for (i = 0; i < priv->num_gphy_fw; i++) gswip_gphy_fw_remove(priv, &priv->gphy_fw[i]); return err; @@ -1134,8 +1134,10 @@ static int gswip_remove(struct platform_device *pdev) dsa_unregister_switch(priv->ds); - if (priv->ds->slave_mii_bus) + if (priv->ds->slave_mii_bus) { mdiobus_unregister(priv->ds->slave_mii_bus); + of_node_put(priv->ds->slave_mii_bus->dev.of_node); + } for (i = 0; i < priv->num_gphy_fw; i++) gswip_gphy_fw_remove(priv, &priv->gphy_fw[i]); From 8bb18f69c71f5fedaded2d0337dd8a0d15b51ea5 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 16 Jan 2019 11:23:35 +0100 Subject: [PATCH 3/3] net: dsa: lantiq_gswip: drop bogus drvdata check The platform-device driver data is set on successful probe and will never be NULL on remove (or we have much bigger problems). Signed-off-by: Johan Hovold Reviewed-by: Andrew Lunn Acked-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/dsa/lantiq_gswip.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c index 5792674dd4e4..27d092cab40e 100644 --- a/drivers/net/dsa/lantiq_gswip.c +++ b/drivers/net/dsa/lantiq_gswip.c @@ -1126,9 +1126,6 @@ static int gswip_remove(struct platform_device *pdev) struct gswip_priv *priv = platform_get_drvdata(pdev); int i; - if (!priv) - return 0; - /* disable the switch */ gswip_mdio_mask(priv, GSWIP_MDIO_GLOB_ENABLE, 0, GSWIP_MDIO_GLOB);