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

From: Rantala, Tommi T. (Nokia - FI/Espoo)
Date: Wed Feb 13 2019 - 11:29:32 EST


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