From: Al Viro <viro@zeniv.linux.org.uk>
Date: Mon, 22 Aug 2016 03:39:47 +0000 (-0400)
Subject: sh: fix copy_from_user()
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=df243b41c66ebad9361bfb75fa022dd168ffb394;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git

sh: fix copy_from_user()

commit 6e050503a150b2126620c1a1e9b3a368fcd51eac upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/arch/sh/include/asm/uaccess.h b/arch/sh/include/asm/uaccess.h
index a49635c51266..92ade79ac427 100644
--- a/arch/sh/include/asm/uaccess.h
+++ b/arch/sh/include/asm/uaccess.h
@@ -151,7 +151,10 @@ copy_from_user(void *to, const void __user *from, unsigned long n)
 	__kernel_size_t __copy_size = (__kernel_size_t) n;
 
 	if (__copy_size && __access_ok(__copy_from, __copy_size))
-		return __copy_user(to, from, __copy_size);
+		__copy_size = __copy_user(to, from, __copy_size);
+
+	if (unlikely(__copy_size))
+		memset(to + (n - __copy_size), 0, __copy_size);
 
 	return __copy_size;
 }