[PATCH net] qlogic: check kstrtoul() for errors

[Dan Carpenter]

We accidentally left out the error handling for kstrtoul().

Fixes: a520030e326a ("qlcnic: Implement flash sysfs callback for 83xx adapter")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>

diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_sysfs.c 
b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_sysfs.c
index 891f03a7a33d..8d7b9bb910f2 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_sysfs.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_sysfs.c
@@ -1128,6 +1128,8 @@ static ssize_t 
qlcnic_83xx_sysfs_flash_write_handler(struct file *filp,
        struct qlcnic_adapter *adapter = dev_get_drvdata(dev);
 
        ret = kstrtoul(buf, 16, &data);
+       if (ret)
+               return ret;
 
        switch (data) {
        case QLC_83XX_FLASH_SECTOR_ERASE_CMD: