From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 69736C65BAF for ; Sun, 9 Dec 2018 22:02:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 391F520672 for ; Sun, 9 Dec 2018 22:02:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 391F520672 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726662AbeLIVzc (ORCPT ); Sun, 9 Dec 2018 16:55:32 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34828 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726421AbeLIVzO (ORCPT ); Sun, 9 Dec 2018 16:55:14 -0500 Received: from pub.yeoldevic.com ([81.174.156.145] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gW72d-0002im-Uy; Sun, 09 Dec 2018 21:55:12 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gW72b-0003KN-Fm; Sun, 09 Dec 2018 21:55:09 +0000 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Wen Xu" , "Theodore Ts'o" Date: Sun, 09 Dec 2018 21:50:33 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 090/328] ext4: check for NUL characters in extended attribute's name In-Reply-To: X-SA-Exim-Connect-IP: 81.174.156.145 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Theodore Ts'o commit 7d95178c77014dbd8dce36ee40bbbc5e6c121ff5 upstream. Extended attribute names are defined to be NUL-terminated, so the name must not contain a NUL character. This is important because there are places when remove extended attribute, the code uses strlen to determine the length of the entry. That should probably be fixed at some point, but code is currently really messy, so the simplest fix for now is to simply validate that the extended attributes are sane. https://bugzilla.kernel.org/show_bug.cgi?id=200401 Reported-by: Wen Xu Signed-off-by: Theodore Ts'o [bwh: Backported to 3.16: return -EIO instead of -EFSCORRUPTED] Signed-off-by: Ben Hutchings --- fs/ext4/xattr.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/ext4/xattr.c +++ b/fs/ext4/xattr.c @@ -193,6 +193,8 @@ ext4_xattr_check_names(struct ext4_xattr struct ext4_xattr_entry *next = EXT4_XATTR_NEXT(e); if ((void *)next >= end) return -EIO; + if (strnlen(e->e_name, e->e_name_len) != e->e_name_len) + return -EIO; e = next; }