watchdog: rc32434_wdt: fix ioctl error handling

Calling return copy_to_user(...) in an ioctl will not do the right thing
if there's a pagefault: copy_to_user returns the number of bytes not
copied in this case.

Fix up watchdog/rc32434_wdt to do
	return copy_to_user(...)) ?  -EFAULT : 0;

instead.

Cc: stable@vger.kernel.org
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Michael S. Tsirkin 2016-02-28 17:44:09 +02:00 committed by Wim Van Sebroeck
parent 972ec35103
commit 10e7ac22cd
1 changed files with 1 additions and 1 deletions

View File

@ -237,7 +237,7 @@ static long rc32434_wdt_ioctl(struct file *file, unsigned int cmd,
return -EINVAL;
/* Fall through */
case WDIOC_GETTIMEOUT:
return copy_to_user(argp, &timeout, sizeof(int));
return copy_to_user(argp, &timeout, sizeof(int)) ? -EFAULT : 0;
default:
return -ENOTTY;
}