mei: mei_write correct checks for copy_from_user

1. return -EFUALT when copy_from_user fails
2. display error message on failure in error level

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index 173ff095be0d..5ff810b1e8b3 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -404,8 +404,11 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
                 goto out;
 
         rets = copy_from_user(write_cb->request_buffer.data, ubuf, length);
-        if (rets)
+        if (rets) {
+                dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
+                rets = -EFAULT;
                 goto out;
+        }
 
         if (cl == &dev->iamthif_cl) {
                 rets = mei_amthif_write(dev, write_cb);
@@ -567,7 +570,7 @@ static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data)
         dev_dbg(&dev->pdev->dev, "copy connect data from user\n");
         if (copy_from_user(connect_data, (char __user *)data,
                                 sizeof(struct mei_connect_client_data))) {
-                dev_dbg(&dev->pdev->dev, "failed to copy data from userland\n");
+                dev_err(&dev->pdev->dev, "failed to copy data from userland\n");
                 rets = -EFAULT;
                 goto out;
         }