[PATCH 07/10] comedi: lift copy_from_user() into callers of __comedi_get_user_cmd()

[Al Viro]

From: Al Viro <v...@zeniv.linux.org.uk>

Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
 drivers/staging/comedi/comedi_fops.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/drivers/staging/comedi/comedi_fops.c 
b/drivers/staging/comedi/comedi_fops.c
index d80a416e70b2..e85a143057a1 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -1649,17 +1649,11 @@ static int do_insn_ioctl(struct comedi_device *dev,
 }
 
 static int __comedi_get_user_cmd(struct comedi_device *dev,
-                                struct comedi_cmd __user *arg,
                                 struct comedi_cmd *cmd)
 {
        struct comedi_subdevice *s;
 
        lockdep_assert_held(&dev->mutex);
-       if (copy_from_user(cmd, arg, sizeof(*cmd))) {
-               dev_dbg(dev->class_dev, "bad cmd address\n");
-               return -EFAULT;
-       }
-
        if (cmd->subdev >= dev->n_subdevices) {
                dev_dbg(dev->class_dev, "%d no such subdevice\n", cmd->subdev);
                return -ENODEV;
@@ -1757,8 +1751,13 @@ static int do_cmd_ioctl(struct comedi_device *dev,
 
        lockdep_assert_held(&dev->mutex);
 
+       if (copy_from_user(&cmd, arg, sizeof(cmd))) {
+               dev_dbg(dev->class_dev, "bad cmd address\n");
+               return -EFAULT;
+       }
+
        /* get the user's cmd and do some simple validation */
-       ret = __comedi_get_user_cmd(dev, arg, &cmd);
+       ret = __comedi_get_user_cmd(dev, &cmd);
        if (ret)
                return ret;
 
@@ -1866,8 +1865,13 @@ static int do_cmdtest_ioctl(struct comedi_device *dev,
 
        lockdep_assert_held(&dev->mutex);
 
+       if (copy_from_user(&cmd, arg, sizeof(cmd))) {
+               dev_dbg(dev->class_dev, "bad cmd address\n");
+               return -EFAULT;
+       }
+
        /* get the user's cmd and do some simple validation */
-       ret = __comedi_get_user_cmd(dev, arg, &cmd);
+       ret = __comedi_get_user_cmd(dev, &cmd);
        if (ret)
                return ret;
 
-- 
2.11.0