From: Al Viro <viro@zeniv.linux.org.uk>
Date: Sat, 20 Aug 2016 20:18:53 +0000 (-0400)
Subject: mips: copy_from_user() must zero the destination on access_ok() failure
X-Git-Tag: v3.16.39~69
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f8be368de3e7b8c637545edff8ffff60a8baf62c;p=linux

mips: copy_from_user() must zero the destination on access_ok() failure

commit e69d700535ac43a18032b3c399c69bf4639e89a2 upstream.

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

diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index 16e0ea6b99d8..cb4a3ee31983 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -14,6 +14,7 @@
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/thread_info.h>
+#include <linux/string.h>
 #include <asm/asm-eva.h>
 
 /*
@@ -1139,6 +1140,8 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
 			__cu_len = __invoke_copy_from_user(__cu_to,	\
 							   __cu_from,	\
 							   __cu_len);   \
+		} else {						\
+			memset(__cu_to, 0, __cu_len);			\
 		}							\
 	}								\
 	__cu_len;							\