[PATCH][V2] net/ethoc: fix null dereference on error exit path

From: Colin King
Date: Wed Jun 01 2016 - 09:16:59 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

priv is assigned to NULL however some of the early error exit paths to
label 'free' dereference priv, causing a null pointer dereference.

Move the label 'free' to just the free_netdev statement, and add a new
exit path 'free2' for the error cases were clk_disable_unprepare needs
calling before the final free.

Fixes issue found by CoverityScan, CID#113260

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/net/ethernet/ethoc.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/ethoc.c b/drivers/net/ethernet/ethoc.c
index 41b0106..4edb98c 100644
--- a/drivers/net/ethernet/ethoc.c
+++ b/drivers/net/ethernet/ethoc.c
@@ -1195,7 +1195,7 @@ static int ethoc_probe(struct platform_device *pdev)
priv->mdio = mdiobus_alloc();
if (!priv->mdio) {
ret = -ENOMEM;
- goto free;
+ goto free2;
}

priv->mdio->name = "ethoc-mdio";
@@ -1208,7 +1208,7 @@ static int ethoc_probe(struct platform_device *pdev)
ret = mdiobus_register(priv->mdio);
if (ret) {
dev_err(&netdev->dev, "failed to register MDIO bus\n");
- goto free;
+ goto free2;
}

ret = ethoc_mdio_probe(netdev);
@@ -1241,9 +1241,10 @@ error2:
error:
mdiobus_unregister(priv->mdio);
mdiobus_free(priv->mdio);
-free:
+free2:
if (priv->clk)
clk_disable_unprepare(priv->clk);
+free:
free_netdev(netdev);
out:
return ret;
--
2.8.1