[PATCH 4.14 1/8] uio: Reduce return paths from uio_write()

["Rantala, Tommi T. (Nokia - FI/Espoo)" <tommi.t.rantala@xxxxxxxxx>]

From: Hamish Martin <hamish.martin@xxxxxxxxxxxxxxxxxxx>

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@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Tommi Rantala <tommi.t.rantala@xxxxxxxxx>
---
 drivers/uio/uio.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index 654579bc1e54..10f249628e79 100644
--- 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);
 }
 
-- 
2.20.1