From a5e541f796f17228793694d64b507f5f57db4cd7 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 18 Aug 2016 21:31:41 -0400 Subject: [PATCH] ia64: copy_from_user() should zero the destination on access_ok() failure Cc: stable@vger.kernel.org Signed-off-by: Al Viro --- arch/ia64/include/asm/uaccess.h | 25 +++++++++++-------------- 1 file changed, 11 insertions(+), 14 deletions(-) diff --git a/arch/ia64/include/asm/uaccess.h b/arch/ia64/include/asm/uaccess.h index 465c70982f40..6c2d2c8c24e8 100644 --- a/arch/ia64/include/asm/uaccess.h +++ b/arch/ia64/include/asm/uaccess.h @@ -272,20 +272,17 @@ __copy_from_user (void *to, const void __user *from, unsigned long count) __cu_len; \ }) -#define copy_from_user(to, from, n) \ -({ \ - void *__cu_to = (to); \ - const void __user *__cu_from = (from); \ - long __cu_len = (n); \ - \ - __chk_user_ptr(__cu_from); \ - if (__access_ok(__cu_from, __cu_len, get_fs())) { \ - if (!__builtin_constant_p(n)) \ - check_object_size(__cu_to, __cu_len, false); \ - __cu_len = __copy_user((__force void __user *) __cu_to, __cu_from, __cu_len); \ - } \ - __cu_len; \ -}) +static inline unsigned long +copy_from_user(void *to, const void __user *from, unsigned long n) +{ + if (!__builtin_constant_p(n)) + check_object_size(to, n, false); + if (likely(__access_ok(from, n, get_fs()))) + n = __copy_user((__force void __user *) to, from, n); + else + memset(to, 0, n); + return n; +} #define __copy_in_user(to, from, size) __copy_user((to), (from), (size)) -- 2.20.1