[PATCH net 1/7] net: ethernet: stmmac: dwmac-socfpga: fix use-after-free on probe errors

[Johan Hovold]

Make sure to call stmmac_dvr_remove() before returning on late probe
errors so that memory is freed, clocks are disabled, and the netdev is
deregistered before its resources go away.

Fixes: 3c201b5a84ed ("net: stmmac: socfpga: Remove re-registration of
reset controller")
Signed-off-by: Johan Hovold <jo...@kernel.org>
---
 .../net/ethernet/stmicro/stmmac/dwmac-socfpga.c    | 29 ++++++++++++++--------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c 
b/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
index bec6963ac71e..47db157da3e8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-socfpga.c
@@ -304,6 +304,8 @@ static int socfpga_dwmac_probe(struct platform_device *pdev)
        struct device           *dev = &pdev->dev;
        int                     ret;
        struct socfpga_dwmac    *dwmac;
+       struct net_device       *ndev;
+       struct stmmac_priv      *stpriv;
 
        ret = stmmac_get_platform_resources(pdev, &stmmac_res);
        if (ret)
@@ -327,19 +329,26 @@ static int socfpga_dwmac_probe(struct platform_device 
*pdev)
        plat_dat->fix_mac_speed = socfpga_dwmac_fix_mac_speed;
 
        ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+       if (ret)
+               return ret;
 
-       if (!ret) {
-               struct net_device *ndev = platform_get_drvdata(pdev);
-               struct stmmac_priv *stpriv = netdev_priv(ndev);
+       ndev = platform_get_drvdata(pdev);
+       stpriv = netdev_priv(ndev);
 
-               /* The socfpga driver needs to control the stmmac reset to
-                * set the phy mode. Create a copy of the core reset handel
-                * so it can be used by the driver later.
-                */
-               dwmac->stmmac_rst = stpriv->stmmac_rst;
+       /* The socfpga driver needs to control the stmmac reset to set the phy
+        * mode. Create a copy of the core reset handle so it can be used by
+        * the driver later.
+        */
+       dwmac->stmmac_rst = stpriv->stmmac_rst;
 
-               ret = socfpga_dwmac_set_phy_mode(dwmac);
-       }
+       ret = socfpga_dwmac_set_phy_mode(dwmac);
+       if (ret)
+               goto err_dvr_remove;
+
+       return 0;
+
+err_dvr_remove:
+       stmmac_dvr_remove(&pdev->dev);
 
        return ret;
 }
-- 
2.7.3