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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D219DC4360C for ; Wed, 2 Oct 2019 19:10:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B65532133F for ; Wed, 2 Oct 2019 19:10:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729865AbfJBTK2 (ORCPT ); Wed, 2 Oct 2019 15:10:28 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35882 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729315AbfJBTIQ (ORCPT ); Wed, 2 Oct 2019 15:08:16 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iFjyx-00035r-HB; Wed, 02 Oct 2019 20:08:15 +0100 Received: from ben by deadeye with local (Exim 4.92.1) (envelope-from ) id 1iFjyp-0003fK-I4; Wed, 02 Oct 2019 20:08:07 +0100 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, Denis Kirjanov , "John Johansen" , "Jann Horn" Date: Wed, 02 Oct 2019 20:06:51 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 68/87] apparmor: enforce nullbyte at end of tag string In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 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 3.16.75-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jann Horn commit 8404d7a674c49278607d19726e0acc0cae299357 upstream. A packed AppArmor policy contains null-terminated tag strings that are read by unpack_nameX(). However, unpack_nameX() uses string functions on them without ensuring that they are actually null-terminated, potentially leading to out-of-bounds accesses. Make sure that the tag string is null-terminated before passing it to strcmp(). Fixes: 736ec752d95e ("AppArmor: policy routines for loading and unpacking policy") Signed-off-by: Jann Horn Signed-off-by: John Johansen Signed-off-by: Ben Hutchings --- security/apparmor/policy_unpack.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -177,7 +177,7 @@ static bool unpack_nameX(struct aa_ext * char *tag = NULL; size_t size = unpack_u16_chunk(e, &tag); /* if a name is specified it must match. otherwise skip tag */ - if (name && (!size || strcmp(name, tag))) + if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag))) goto fail; } else if (name) { /* if a name is specified and there is no name tag fail */