[PATCH 3.2 112/152] mn10300: copy_from_user() should zero on access_ok() failure...

From: Ben Hutchings
Date: Sun Nov 13 2016 - 22:04:17 EST


3.2.84-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit ae7cc577ec2a4a6151c9e928fd1f595d953ecef1 upstream.

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.2: include <linux/string.h> to get declaration of memset()]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/mn10300/lib/usercopy.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/arch/mn10300/lib/usercopy.c
+++ b/arch/mn10300/lib/usercopy.c
@@ -9,7 +9,8 @@
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
-#include <asm/uaccess.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>

unsigned long
__generic_copy_to_user(void *to, const void *from, unsigned long n)
@@ -24,6 +25,8 @@ __generic_copy_from_user(void *to, const
{
if (access_ok(VERIFY_READ, from, n))
__copy_user_zeroing(to, from, n);
+ else
+ memset(to, 0, n);
return n;
}