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=-2.5 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 F2850C10F00 for ; Wed, 6 Mar 2019 20:46:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C364D20657 for ; Wed, 6 Mar 2019 20:46:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=tycho-ws.20150623.gappssmtp.com header.i=@tycho-ws.20150623.gappssmtp.com header.b="ILCMLu3J" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726804AbfCFUqP (ORCPT ); Wed, 6 Mar 2019 15:46:15 -0500 Received: from mail-yw1-f68.google.com ([209.85.161.68]:41867 "EHLO mail-yw1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726626AbfCFUqP (ORCPT ); Wed, 6 Mar 2019 15:46:15 -0500 Received: by mail-yw1-f68.google.com with SMTP id q128so11254200ywg.8 for ; Wed, 06 Mar 2019 12:46:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tycho-ws.20150623.gappssmtp.com; s=20150623; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=FlQ1pcWvvsqF6RZpvT/LXNlOVdVPkEXR+sAsFDFnBdk=; b=ILCMLu3JjB9VIVpWIcPdYd6U9fh2ZWn+UiYwnKJSwWj21lYl73riyTeID0655yx1Pr LQSR+PAIW6lNfgA5pq1+0WYZqKKKp7v0XodaAkeasA8N3LZl8XxEMJtsv6157Ju6G/eJ NnqZr41k7rDB9rXlnxjdLDWHQQzqcfQDIyq3N+YfBUvtkd9W0NnT8ICp872sNjeMU3pX X5kl9jlBAGf16F4JrvQO2Ff8emkb36F/Ndsmmwqe7PDQfOayPAqCnmCt6p11IX2hji4O 1v8FkVPO3y2jDkD+q44sQ6HQpMvnysfRvWHqr1qXcGwZmgkhhll4fHAKscwyMK6ptwF9 M2tw== 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:references :mime-version:content-disposition:in-reply-to:user-agent; bh=FlQ1pcWvvsqF6RZpvT/LXNlOVdVPkEXR+sAsFDFnBdk=; b=R+nvWx7N+g4p2gptrnlz484szgdy7zysknCRPQADAu8f17RE6kqJk8z6EDlx9Qr6+U qFqn4vy23wE1QnYQ47cHErKeFlqmWEB6mdOQGJ3XZvcOw9b/AMuOvaxsH0Qyb9YtR9Ke FRsRvYHNpM72ROT6NBhgOKNWwS4YaM6PSQpYcE7Z9yS87jWkEntsk+X240cWKjEXMZI8 zORoXIVmF6qRbVTUh2MeToKIHBAW7fJr7KDQmdliU4AJ1zcy+WmzwPXzUZDoJvLUZ+lA yKda3dNe4x0GJWbypbQa3823ygEeWMiOtbR0dCD1KoMHQK/EpnU9diVL0Ju9nIBd9SuW gR2g== X-Gm-Message-State: APjAAAWFiw1Imzb9zvciVRZXnT2tKp04F6yFxtDBcE/HJJkRkiz/UTDP Wc/PcrSDsWN+pEp93G/zPtPflg== X-Google-Smtp-Source: APXvYqy3+RH5AZ/9D9pGBv8HyhmXitQxIDq2Au/fojdxR7pHCbuj8dko/wPbgkXpCKQ/bdE7GSueHA== X-Received: by 2002:a25:7582:: with SMTP id q124mr8702778ybc.136.1551905174094; Wed, 06 Mar 2019 12:46:14 -0800 (PST) Received: from cisco ([2601:282:901:dd7b:316c:2a55:1ab5:9f1c]) by smtp.gmail.com with ESMTPSA id v198sm877150ywv.24.2019.03.06.12.46.12 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Wed, 06 Mar 2019 12:46:13 -0800 (PST) Date: Wed, 6 Mar 2019 13:46:11 -0700 From: Tycho Andersen To: Christian Brauner Cc: Kees Cook , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH 2/2] seccomp: disallow NEW_LISTENER and TSYNC flags Message-ID: <20190306204611.GH7413@cisco> References: <20190306201413.14153-1-tycho@tycho.ws> <20190306201413.14153-2-tycho@tycho.ws> <20190306203932.im7lkblvmd227td3@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190306203932.im7lkblvmd227td3@gmail.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 06, 2019 at 09:39:35PM +0100, Christian Brauner wrote: > > + > > /* Prepare the new filter before holding any locks. */ > > prepared = seccomp_prepare_user_filter(filter); > > if (IS_ERR(prepared)) > > @@ -1302,7 +1315,7 @@ static long seccomp_set_mode_filter(unsigned int flags, > > mutex_unlock(¤t->signal->cred_guard_mutex); > > out_put_fd: > > if (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) { > > - if (ret < 0) { > > + if (ret) { > > Why that change but keep checking if (ret < 0) further up? Not sure what you mean here. The only other place I see that we check something is < 0 in that function is the return value of get_unused_fd_flags(), which looks right to me? Tycho