[PATCH] net: phy: phy: check return value of bus write

[Aditya Pakki]

phy_mii_ioctl() could fail when writing to the bus via
mdiobus_write(). The fix adds a check and returns an error in case
of failure.

Signed-off-by: Aditya Pakki <pakki...@umn.edu>
---
 drivers/net/phy/phy.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 1d73ac3309ce..1fbdaa96b36e 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -397,6 +397,7 @@ int phy_mii_ioctl(struct phy_device *phydev, struct ifreq 
*ifr, int cmd)
        struct mii_ioctl_data *mii_data = if_mii(ifr);
        u16 val = mii_data->val_in;
        bool change_autoneg = false;
+       int rc;
 
        switch (cmd) {
        case SIOCGMIIPHY:
@@ -443,8 +444,10 @@ int phy_mii_ioctl(struct phy_device *phydev, struct ifreq 
*ifr, int cmd)
                        }
                }
 
-               mdiobus_write(phydev->mdio.bus, mii_data->phy_id,
-                             mii_data->reg_num, val);
+               rc = mdiobus_write(phydev->mdio.bus, mii_data->phy_id,
+                                  mii_data->reg_num, val);
+               if (rc)
+                       return rc;
 
                if (mii_data->phy_id == phydev->mdio.addr &&
                    mii_data->reg_num == MII_BMCR &&
-- 
2.17.1