From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S941223AbcIVSzw (ORCPT ); Thu, 22 Sep 2016 14:55:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:56638 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938762AbcIVRiJ (ORCPT ); Thu, 22 Sep 2016 13:38:09 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro Subject: [PATCH 4.4 109/118] alpha: fix copy_from_user() Date: Thu, 22 Sep 2016 19:30:09 +0200 Message-Id: <20160922172944.074586867@linuxfoundation.org> X-Mailer: git-send-email 2.10.0 In-Reply-To: <20160922172938.643879685@linuxfoundation.org> References: <20160922172938.643879685@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit 2561d309dfd1555e781484af757ed0115035ddb3 upstream. it should clear the destination even when access_ok() fails. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- arch/alpha/include/asm/uaccess.h | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) --- a/arch/alpha/include/asm/uaccess.h +++ b/arch/alpha/include/asm/uaccess.h @@ -371,14 +371,6 @@ __copy_tofrom_user_nocheck(void *to, con return __cu_len; } -extern inline long -__copy_tofrom_user(void *to, const void *from, long len, const void __user *validate) -{ - if (__access_ok((unsigned long)validate, len, get_fs())) - len = __copy_tofrom_user_nocheck(to, from, len); - return len; -} - #define __copy_to_user(to, from, n) \ ({ \ __chk_user_ptr(to); \ @@ -393,17 +385,22 @@ __copy_tofrom_user(void *to, const void #define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user - extern inline long copy_to_user(void __user *to, const void *from, long n) { - return __copy_tofrom_user((__force void *)to, from, n, to); + if (likely(__access_ok((unsigned long)to, n, get_fs()))) + n = __copy_tofrom_user_nocheck((__force void *)to, from, n); + return n; } extern inline long copy_from_user(void *to, const void __user *from, long n) { - return __copy_tofrom_user(to, (__force void *)from, n, from); + if (likely(__access_ok((unsigned long)from, n, get_fs()))) + n = __copy_tofrom_user_nocheck(to, (__force void *)from, n); + else + memset(to, 0, n); + return n; } extern void __do_clear_user(void);