From ab0aca27c4dfcfa72eb1339ae94edbfbdd751ae8 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 20 Mar 2017 11:54:21 -0400 Subject: [PATCH] mips: make copy_from_user() zero tail explicitly Signed-off-by: Al Viro --- arch/mips/include/asm/uaccess.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h index 9c05262a85f3..712dc40625b6 100644 --- a/arch/mips/include/asm/uaccess.h +++ b/arch/mips/include/asm/uaccess.h @@ -1080,29 +1080,29 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n); ({ \ void *__cu_to; \ const void __user *__cu_from; \ - long __cu_len; \ + long __cu_len, __cu_res; \ \ __cu_to = (to); \ __cu_from = (from); \ - __cu_len = (n); \ + __cu_res = __cu_len = (n); \ \ check_object_size(__cu_to, __cu_len, false); \ \ if (eva_kernel_access()) { \ - __cu_len = __invoke_copy_from_kernel(__cu_to, \ + __cu_res = __invoke_copy_from_kernel(__cu_to, \ __cu_from, \ __cu_len); \ } else { \ if (access_ok(VERIFY_READ, __cu_from, __cu_len)) { \ might_fault(); \ - __cu_len = __invoke_copy_from_user(__cu_to, \ + __cu_res = __invoke_copy_from_user(__cu_to, \ __cu_from, \ __cu_len); \ - } else { \ - memset(__cu_to, 0, __cu_len); \ } \ } \ - __cu_len; \ + if (unlikely(__cu_res)) \ + memset(__cu_to + __cu_len - __cu_res, 0, __cu_res); \ + __cu_res; \ }) #define __copy_in_user(to, from, n) \