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=-8.4 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 0A277C04AB6 for ; Sat, 1 Jun 2019 02:15:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6BA3270AA for ; Sat, 1 Jun 2019 02:15:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="rWBCB21H" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727075AbfFACPn (ORCPT ); Fri, 31 May 2019 22:15:43 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:45683 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726708AbfFACPn (ORCPT ); Fri, 31 May 2019 22:15:43 -0400 Received: by mail-pg1-f194.google.com with SMTP id w34so4987048pga.12; Fri, 31 May 2019 19:15:42 -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=lTR0jTl5oD+Gm74Vzo4HY2zyqfQyqs0HXRg7trWVZDw=; b=rWBCB21HCyCQmjsTX5J+I8l8H9HdFrpIbABMMBZUeEykp/hqFwNyZA0QeFPrXhGpXM bVPFXYL0+LV36Q2SUZ7TamxilUye1NU1qZV3m1Mf9QBP0+cMdq4zvWa3DH1jYsdCoWIA SI9FfgJOEW+H7i4RAxxxUSNp//6rza4EPdPi1juhCaeTWG077LuqbCBjuOOz9T05vsyD iz6zyS1/4SVzPx5ZrWVt7nZUVkzDVaLJ+QZofE4Lb40EmZ5DNJWVWW/o2v9D9GM1uH2p f24y0AGYWNaOp5gxh/0AeQ37jRj9bWjFX6KSc0/Yvwn/JaQrIbgdfwRGbw+UvIVLDOs7 yI3g== 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=lTR0jTl5oD+Gm74Vzo4HY2zyqfQyqs0HXRg7trWVZDw=; b=pH/OGEflFicb8ovpwhXDq4JVDHm0mveWRTcgT04pB1laJs1GZ4YyGPZPXWDTFwgavd LM1x5kStGwkALfdQb0PVb0Z59yrUALJCnA83mKsENvvl9nBi96s7DphemP5WeYnhx6An bxlRLDAPyIuc3RDHT1sjM6C3sXxEz0fffh87nfbUALr3mgeT8AlqqFU1R+FStUE41gTi jOzkIxBci8+3qXlcuXgDoh4wOi7aO6n9GtJAf+bjJONnydv0HsAAJz/txCRkmANqLSCL /g6CmseLkicVHBr7X7h7moH7ZfPpgsZ1fiuCCNJRRneqflnweX66u6HLLr4ZT0cVwLVB OngA== X-Gm-Message-State: APjAAAUZz3I42PnAHPAvmiy+8Ssyln6ZDuLXlXOR6imT0czJ5/HjQJZg 8P+9lnznvjVrjCU6ghYPlL0= X-Google-Smtp-Source: APXvYqw2UcKBg8KaCjlDxLjTX9foxqDY1SJrvZ1GppBqpCOrlc8ZOaEwdnuQZ7jf5NzrAX0z8BQ21Q== X-Received: by 2002:aa7:9356:: with SMTP id 22mr14098622pfn.188.1559355342480; Fri, 31 May 2019 19:15:42 -0700 (PDT) Received: from zhanggen-UX430UQ ([66.42.35.75]) by smtp.gmail.com with ESMTPSA id c17sm7934773pfo.114.2019.05.31.19.15.35 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 31 May 2019 19:15:41 -0700 (PDT) Date: Sat, 1 Jun 2019 10:15:26 +0800 From: Gen Zhang To: paul@paul-moore.com, sds@tycho.nsa.gov, eparis@parisplace.org Cc: omosnace@redhat.com, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org Subject: [PATCH v3] selinux: lsm: fix a missing-check bug in selinux_sb_eat_lsm_opts() Message-ID: <20190601021526.GA8264@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: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In selinux_sb_eat_lsm_opts(), 'arg' is allocated by kmemdup_nul(). It returns NULL when fails. So 'arg' should be checked. And 'mnt_opts' should be freed when error. Signed-off-by: Gen Zhang Reviewed-by: Ondrej Mosnacek Fixes: 99dbbb593fe6 ("selinux: rewrite selinux_sb_eat_lsm_opts()") --- diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3ec702c..f329fc0 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2616,6 +2616,7 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) char *from = options; char *to = options; bool first = true; + int ret; while (1) { int len = opt_len(from); @@ -2635,15 +2636,16 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) *q++ = c; } arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); + if (!arg) { + ret = -ENOMEM; + goto free_opt; + } } rc = selinux_add_opt(token, arg, mnt_opts); if (unlikely(rc)) { + ret = rc; kfree(arg); - if (*mnt_opts) { - selinux_free_mnt_opts(*mnt_opts); - *mnt_opts = NULL; - } - return rc; + goto free_opt; } } else { if (!first) { // copy with preceding comma @@ -2661,6 +2663,12 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) } *to = '\0'; return 0; +free_opt: + if (*mnt_opts) { + selinux_free_mnt_opts(*mnt_opts); + *mnt_opts = NULL; + } + return ret; } static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)