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=-8.1 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=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 2B3C9C31E46 for ; Wed, 12 Jun 2019 13:51:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE566208CA for ; Wed, 12 Jun 2019 13:51:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="oq4e53UV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2408080AbfFLNvY (ORCPT ); Wed, 12 Jun 2019 09:51:24 -0400 Received: from mail-wr1-f68.google.com ([209.85.221.68]:36111 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2407647AbfFLNvY (ORCPT ); Wed, 12 Jun 2019 09:51:24 -0400 Received: by mail-wr1-f68.google.com with SMTP id n4so17051017wrs.3; Wed, 12 Jun 2019 06:51:23 -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=rRZQ5CvqSo7Zb8yh0zW1MKbjakdIyzMfR0PSu30HFO8=; b=oq4e53UVMW1SsJJj/duLOfdOZ6GzRsQ4BiFAUCz5uhdn9GKeV76nGWMmy+7rHmoMFD 80bfKfEJ69EkIBDnTXpZgHzrqEWw4I58peCNhNO1uP74xiDt1cbN+P09WM9CA/863F35 H/shk5rpo2/RMeSW/QmZ1kDBPhAFpzgNJSqvyLRf2yCSS6+I0+J3PBzeacLq6fVTlCuI KX3SdouymQ9Q1zEwTPSHFgtwTJPeurlTHf5wkSXM5qVs+CW2rXm6t6nN75l9tDP5sU9Q P5Tj3Wu8AF28UbnQOU4ApcFgPjz/UAWupZbKg3msgwbSB4KaDqhMNT0Q8PXNMmNkbm30 6kIQ== 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=rRZQ5CvqSo7Zb8yh0zW1MKbjakdIyzMfR0PSu30HFO8=; b=gw26wyOxZnJIyZJ+gzUyNJpoSEDwW13YBjyj4Qb64PtPnCMthTCB8TFEPy3PQ22Da4 qFE/TpnukWqzmvZf7PLePg0Xkd0R1uIs4n3UleQQ8+NnY2e0ckZA9qccXJ/LosK18yF9 R0otJwCN6yS8q2t1QWGtEmB1/dc/O/zObQ0uoBda5pPLSQd0yvRusbjSycfaeARWvdlM BIzhryft6gAhyo1mm7uhuj3u0QF36d9kxym7mm6tApART9NhofyH4CcNdaVaUohl9dg1 0Lmw8qIU9Xpd0bOUD3V8OZJTrhdl2p0GLzwPAidlRUx85a9iQ62AVhgSVDV/aa8O6D2q 91iQ== X-Gm-Message-State: APjAAAV1vyMDljHuSkHuLCFx9pprEc09hIWF20nCg0X/OYsmeFpgEUtE GfSICV8HLFSHrxMKrP3TG9A= X-Google-Smtp-Source: APXvYqywrTlGs5MRkvztt/cIkFDfZTxl0Cd9acK0tvSiV2JH/7v5bKa0nA+YEjgqXOSG7ZwDOxjoFQ== X-Received: by 2002:a05:6000:1285:: with SMTP id f5mr14215564wrx.85.1560347482708; Wed, 12 Jun 2019 06:51:22 -0700 (PDT) Received: from zhanggen-UX430UQ ([108.61.173.19]) by smtp.gmail.com with ESMTPSA id c2sm18147195wrf.75.2019.06.12.06.51.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 12 Jun 2019 06:51:22 -0700 (PDT) Date: Wed, 12 Jun 2019 21:51:14 +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 v5] selinux: fix a missing-check bug in selinux_sb_eat_lsm_opts() Message-ID: <20190612135114.GB4015@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: selinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: selinux@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 Fixes: 99dbbb593fe6 ("selinux: rewrite selinux_sb_eat_lsm_opts()") diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 3ec702c..7a56f2a 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2616,10 +2616,11 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) char *from = options; char *to = options; bool first = true; + int rc; while (1) { int len = opt_len(from); - int token, rc; + int token; char *arg = NULL; token = match_opt_prefix(from, len, &arg); @@ -2635,15 +2636,15 @@ static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts) *q++ = c; } arg = kmemdup_nul(arg, q - arg, GFP_KERNEL); + if (!arg) { + rc = -ENOMEM; + goto free_opt; + } } rc = selinux_add_opt(token, arg, mnt_opts); if (unlikely(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 +2662,13 @@ 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 rc; } static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)