net: stmmac: add sanity check to device_property_read_u32_array call

Currently the call to device_property_read_u32_array is not error checked
leading to potential garbage values in the delays array that are then used
in msleep delays.  Add a sanity check to the property fetching.

Addresses-Coverity: ("Uninitialized scalar variable")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index da310de..5b7923c 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -242,6 +242,7 @@ int stmmac_mdio_reset(struct mii_bus *bus)
        if (priv->device->of_node) {
                struct gpio_desc *reset_gpio;
                u32 delays[3];
+               int ret;
 
                reset_gpio = devm_gpiod_get_optional(priv->device,
                                                     "snps,reset",
@@ -249,9 +250,15 @@ int stmmac_mdio_reset(struct mii_bus *bus)
                if (IS_ERR(reset_gpio))
                        return PTR_ERR(reset_gpio);
 
-               device_property_read_u32_array(priv->device,
-                                              "snps,reset-delays-us",
-                                              delays, ARRAY_SIZE(delays));
+               ret = device_property_read_u32_array(priv->device,
+                                                    "snps,reset-delays-us",
+                                                    delays,
+                                                    ARRAY_SIZE(delays));
+               if (ret) {
+                       dev_err(ndev->dev.parent,
+                               "invalid property snps,reset-delays-us\n");
+                       return -EINVAL;
+               }
 
                if (delays[0])
                        msleep(DIV_ROUND_UP(delays[0], 1000));