pxa168: fix double deallocation of managed resources

Commit 43d3ddf87a57 ("net: pxa168_eth: add device tree support") starts
to use managed resources by adding devm_clk_get() and
devm_ioremap_resource(), but it leaves explicit iounmap() and clock_put()
in pxa168_eth_remove() and in failure handling code of pxa168_eth_probe().
As a result double free can happen.

The patch removes explicit resource deallocation. Also it converts
clk_disable() to clk_disable_unprepare() to make it symmetrical with
clk_prepare_enable().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 11 deletions

diff --git a/drivers/net/ethernet/marvell/pxa168_eth.c b/drivers/net/ethernet/marvell/pxa168_eth.c
index af829c578400..7ace07dad6a3 100644
--- a/drivers/net/ethernet/marvell/pxa168_eth.c
+++ b/drivers/net/ethernet/marvell/pxa168_eth.c
@@ -1508,7 +1508,8 @@ static int pxa168_eth_probe(struct platform_device *pdev)
                 np = of_parse_phandle(pdev->dev.of_node, "phy-handle", 0);
                 if (!np) {
                         dev_err(&pdev->dev, "missing phy-handle\n");
-                        return -EINVAL;
+                        err = -EINVAL;
+                        goto err_netdev;
                 }
                 of_property_read_u32(np, "reg", &pep->phy_addr);
                 pep->phy_intf = of_get_phy_mode(pdev->dev.of_node);
@@ -1526,7 +1527,7 @@ static int pxa168_eth_probe(struct platform_device *pdev)
         pep->smi_bus = mdiobus_alloc();
         if (pep->smi_bus == NULL) {
                 err = -ENOMEM;
-                goto err_base;
+                goto err_netdev;
         }
         pep->smi_bus->priv = pep;
         pep->smi_bus->name = "pxa168_eth smi";
@@ -1551,13 +1552,10 @@ err_mdiobus:
         mdiobus_unregister(pep->smi_bus);
 err_free_mdio:
         mdiobus_free(pep->smi_bus);
-err_base:
-        iounmap(pep->base);
 err_netdev:
         free_netdev(dev);
 err_clk:
-        clk_disable(clk);
-        clk_put(clk);
+        clk_disable_unprepare(clk);
         return err;
 }
 
@@ -1574,13 +1572,9 @@ static int pxa168_eth_remove(struct platform_device *pdev)
         if (pep->phy)
                 phy_disconnect(pep->phy);
         if (pep->clk) {
-                clk_disable(pep->clk);
-                clk_put(pep->clk);
-                pep->clk = NULL;
+                clk_disable_unprepare(pep->clk);
         }
 
-        iounmap(pep->base);
-        pep->base = NULL;
         mdiobus_unregister(pep->smi_bus);
         mdiobus_free(pep->smi_bus);
         unregister_netdev(dev);