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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable 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 8968EC04AB5 for ; Thu, 6 Jun 2019 09:23:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 62B3F20868 for ; Thu, 6 Jun 2019 09:23:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="gankvxH1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727855AbfFFJXv (ORCPT ); Thu, 6 Jun 2019 05:23:51 -0400 Received: from mail-wm1-f68.google.com ([209.85.128.68]:50708 "EHLO mail-wm1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727540AbfFFJXv (ORCPT ); Thu, 6 Jun 2019 05:23:51 -0400 Received: by mail-wm1-f68.google.com with SMTP id f204so1660170wme.0; Thu, 06 Jun 2019 02:23:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=O+5z4ntuwugi22GIdYLSWkg/2i3n1YVE12LtK518dm8=; b=gankvxH1paBk1TRo7A5ugeSx/VRzXtByYA1W8dgck+dsa+6pJ6fRxRHqv5xdbiHFHJ 7DLrn0B+QLGVSU/AOqHMIb5uEIC/V+j6XmLwz4B0RjMBd+7O9xZnntLqXcqs/xcU3T+5 CmcCWckQPPo2btsqDg7gSw/JMbXAbj0oG5RQySMalFcsdNHDknJx7MGCftkCMpSF8q4u door876VMoxYlFaMY5PUPaUPenwE2a1I5Of32r4jPVPk0W9+AE/gbZUK6e3la+vwni/Y CuCt39RV/qvPLVQEMd5VGOaLrcK0N2K+f7eG/2N6rHYqN75fuKEkhRb51qSy+PJM9mXy czGg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=O+5z4ntuwugi22GIdYLSWkg/2i3n1YVE12LtK518dm8=; b=SPsCD2sFGGzi8VGa6G2dzUCN0evjrjsVXPkTvoi4nJRiGdfGpu+4MU13C7sxtgYFRg MKI20rbhx/cDc+ppwR9l6tVkHLi7rUNX4MLIu6SankkXxfuMqQJev2IidTIPeIzcI32w GRN6byIS2beSqu9PSc8R1HxX2/8DwgrFh8vZo9fSxeQwIfqidh02bruQu9dAMe+uBTSY YK9Ca68sQXd2zzrH1k+Co0yTlm5B5zDqGkiuiCslYGubFGROR2uXexyOGanA0mNInGgH ocWvKCGh88IxF50USY+JhwBtwnTDwCUHC/vYPdrHmA9YNHnDv13JVIaVgWH4O8o78EN4 xLUA== X-Gm-Message-State: APjAAAXJSEmgvBJMz8rrvg9BzfYL7fBVjn65lmSUYLjckqmNM7QRWaNa mjBU2g9wqF5c3fH2By7xCAM= X-Google-Smtp-Source: APXvYqzRJaLWZGWDtV+1oqoFuiQ/TF/KG8q4YJiF7E8ofqWh/JqjeE+iJEwLRgzTC4X22TWOoGItDQ== X-Received: by 2002:a1c:c74a:: with SMTP id x71mr25796918wmf.121.1559813029331; Thu, 06 Jun 2019 02:23:49 -0700 (PDT) Received: from zhanggen-UX430UQ ([108.61.173.19]) by smtp.gmail.com with ESMTPSA id j15sm1300940wrn.50.2019.06.06.02.23.46 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 06 Jun 2019 02:23:48 -0700 (PDT) Date: Thu, 6 Jun 2019 17:23:42 +0800 From: Gen Zhang To: paul@paul-moore.com, sds@tycho.nsa.gov, eparis@parisplace.org Cc: selinux@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3] selinux: lsm: fix a missing-check bug in selinux_add_mnt_opt( ) Message-ID: <20190606092342.GA21672@zhanggen-UX430UQ> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In selinux_add_mnt_opt(), 'val' is allocated by kmemdup_nul(). It returns NULL when fails. So 'val' should be checked. And 'mnt_opts' should be freed when error. Signed-off-by: Gen Zhang Fixes: 757cbe597fe8 ("LSM: new method: ->sb_add_mnt_opt()") --- diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3ec702c..4e4c1c6 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -1052,15 +1052,23 @@ static int selinux_add_mnt_opt(const char *option, const char *val, int len, if (token == Opt_error) return -EINVAL; - if (token != Opt_seclabel) - val = kmemdup_nul(val, len, GFP_KERNEL); + if (token != Opt_seclabel) { + val = kmemdup_nul(val, len, GFP_KERNEL); + if (!val) { + rc = -ENOMEM; + goto free_opt; + } + } rc = selinux_add_opt(token, val, mnt_opts); if (unlikely(rc)) { kfree(val); - if (*mnt_opts) { - selinux_free_mnt_opts(*mnt_opts); - *mnt_opts = NULL; - } + goto free_opt; + } + return rc; +free_opt: + if (*mnt_opts) { + selinux_free_mnt_opts(*mnt_opts); + *mnt_opts = NULL; } return rc; }