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-Tag: v3.2.84~33
X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=commitdiff_plain;h=6089b5ee9c5f2de2bae342da15afe8d4124b9ebe;ds=sidebyside

sh: fix copy_from_user()

commit 6e050503a150b2126620c1a1e9b3a368fcd51eac upstream.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/arch/sh/include/asm/uaccess.h b/arch/sh/include/asm/uaccess.h
index 075848f43b6a..0e7971185be5 100644
--- a/arch/sh/include/asm/uaccess.h
+++ b/arch/sh/include/asm/uaccess.h
@@ -175,7 +175,10 @@ 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;
 }