uio: Reduce return paths from uio_write()

BugLink: https://bugs.launchpad.net/bugs/1837664
commit 81daa406c2cc97d85eef9409400404efc2a3f756 upstream.

Drive all return paths for uio_write() through a single block at the
end of the function.

Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 654579bc1e54b85b328772397202f6cab50d163b..10f249628e790c27cecb18e44da3981bdbf22ba3 100644 (file)
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -570,20 +570,29 @@ static ssize_t uio_write(struct file *filep, const char __user *buf,
        ssize_t retval;
        s32 irq_on;
 
-       if (!idev->info->irq)
-               return -EIO;
+       if (!idev->info->irq) {
+               retval = -EIO;
+               goto out;
+       }
 
-       if (count != sizeof(s32))
-               return -EINVAL;
+       if (count != sizeof(s32)) {
+               retval = -EINVAL;
+               goto out;
+       }
 
-       if (!idev->info->irqcontrol)
-               return -ENOSYS;
+       if (!idev->info->irqcontrol) {
+               retval = -ENOSYS;
+               goto out;
+       }
 
-       if (copy_from_user(&irq_on, buf, count))
-               return -EFAULT;
+       if (copy_from_user(&irq_on, buf, count)) {
+               retval = -EFAULT;
+               goto out;
+       }
 
        retval = idev->info->irqcontrol(idev->info, irq_on);
 
+out:
        return retval ? retval : sizeof(s32);
 }