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=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 78F82C35669 for ; Sat, 22 Feb 2020 04:26:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4CD2E20707 for ; Sat, 22 Feb 2020 04:26:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="HC6tB5/n" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728040AbgBVE0I (ORCPT ); Fri, 21 Feb 2020 23:26:08 -0500 Received: from mail-pg1-f193.google.com ([209.85.215.193]:38550 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726198AbgBVE0H (ORCPT ); Fri, 21 Feb 2020 23:26:07 -0500 Received: by mail-pg1-f193.google.com with SMTP id d6so2018095pgn.5 for ; Fri, 21 Feb 2020 20:26:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=S04MpDY/ruT9R3530Z87j5UAy18sgkgPvdS5rq+kd3k=; b=HC6tB5/n3jprjIUAPVp7s8TE+lw3DArPemCjTLFf6SZTq8rdljmvjDQKfwnpDCqu9M McuEh8+mx8FGgpNOPUbP/5TCKlQV1w1VEu4/HSjSNXVsfPT9ASGqbZKiIFvVJAlUrr86 aZuMUWYfnYI9yYDHnbwRw6bEQzeTrErT1JXZM= 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; bh=S04MpDY/ruT9R3530Z87j5UAy18sgkgPvdS5rq+kd3k=; b=gNrXHUEJEnN/htxXRPnMlUrdovgqI0S4jB+1ESFUCsQPH0Rz9RzEHxiBpEEeQZ4QxZ DJyyx2kZQAF6siLOCZNAJBsrfrzKeta1HfvBF7/PifhyqKv3FXerkvCM/KGwcYDoDzXM VzQ2sDUtNIKi5LqL0Q3e6edxlarE3r7pzG8OK8OQnMDY0NvYK8gK2FpRVrjlHu+/YxsX W3YXb3sa17lPO2RpNYscn6RT8KBHU0+OUQcfYwq4X6Im7WOPsBAMX2Wk6OUap7JLCX6c tNoF+8nYEWov8wUBLh0qUTEuYpc1TKkDpHWppgnDukKy98COzDRAAimeSB5DJRwzwo7W bLjw== X-Gm-Message-State: APjAAAWBC5xhD0zzdWQH03YLHbnQdJ2Vi0P3pi/EqJRkMmmdK5U7OVT5 ttm2Dce+vA2dK96JpMQxIHyTTQ== X-Google-Smtp-Source: APXvYqynLpaT1SHFc7hteRLE/Am8rkGvVcqos0AxtZQFh6Ok/U/TQctt8ObsfFGGlRMXV0KtzIJk4Q== X-Received: by 2002:a62:1548:: with SMTP id 69mr41986772pfv.239.1582345566578; Fri, 21 Feb 2020 20:26:06 -0800 (PST) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id c15sm4342928pfo.137.2020.02.21.20.26.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Feb 2020 20:26:05 -0800 (PST) Date: Fri, 21 Feb 2020 20:26:04 -0800 From: Kees Cook To: KP Singh Cc: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-security-module@vger.kernel.org, Alexei Starovoitov , Daniel Borkmann , James Morris , Thomas Garnier , Michael Halcrow , Paul Turner , Brendan Gregg , Jann Horn , Matthew Garrett , Christian Brauner , Florent Revest , Brendan Jackman , Martin KaFai Lau , Song Liu , Yonghong Song , "Serge E. Hallyn" , "David S. Miller" , Greg Kroah-Hartman , Nicolas Ferre , Stanislav Fomichev , Quentin Monnet , Andrey Ignatov , Joe Stringer Subject: Re: [PATCH bpf-next v4 4/8] bpf: lsm: Add support for enabling/disabling BPF hooks Message-ID: <202002212023.1712A8AB@keescook> References: <20200220175250.10795-1-kpsingh@chromium.org> <20200220175250.10795-5-kpsingh@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200220175250.10795-5-kpsingh@chromium.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 20, 2020 at 06:52:46PM +0100, KP Singh wrote: > index aa111392a700..569cc07d5e34 100644 > --- a/security/security.c > +++ b/security/security.c > @@ -804,6 +804,13 @@ int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) > break; > } > } > +#ifdef CONFIG_BPF_LSM > + if (HAS_BPF_LSM_PROG(vm_enough_memory)) { > + rc = bpf_lsm_vm_enough_memory(mm, pages); > + if (rc <= 0) > + cap_sys_admin = 0; > + } > +#endif This pattern of using #ifdef in code is not considered best practice. Using in-code IS_ENABLED(CONFIG_BPF_LSM) is preferred. But since this pattern always uses HAS_BPF_LSM_PROG(), you could fold the IS_ENABLED() into the definition of HAS_BPF_LSM_PROG itself -- or more likely, have the macro defined as: #ifdef CONFIG_BPF_LSM # define HAS_BPF_LSM_PROG(x) ....existing implementation.... #else # define HAS_BPF_LSM_PROG(x) false #endif Then none of these ifdefs are needed. -- Kees Cook