Received: by 2002:a05:6a11:4021:0:0:0:0 with SMTP id ky33csp1090490pxb; Wed, 29 Sep 2021 17:02:28 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxdPAmimrSuMDbWvfomP/O15EeV0TdoogoEz/EdtXWNWTvU5KXEotxmXMFtfG2Kqdlj9X+R X-Received: by 2002:a05:6a00:a23:b0:43d:e856:a3d4 with SMTP id p35-20020a056a000a2300b0043de856a3d4mr1195139pfh.17.1632960148747; Wed, 29 Sep 2021 17:02:28 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1632960148; cv=none; d=google.com; s=arc-20160816; b=oisxrUKs0yGc7Ge4IIN66LDt110G6gFBmzNeOe+LhdJ3tgwUoIc2VczEFwTFV1Wnzz Lpa6xwjFfVdpPtWUAj7ivcoilCCGRqD1jyJRTRycosA9MnHJOUGmQFewGi0P2tPSqv1D fsYIOJTkpC4BO3dMhPvKo90x4fXkJyiaWGg09XbCEshHadFnf6VwWgWuJdG3v8T4iB4T G9HXlwCcpHas3CAT2TWGT6Om6ChZE9sMdVeApjK/YafRs6ldNAW1f3QJW5PiOx+Jb5ui D6PcuI57b3VfizDYijtoaEuI92YW6gDiQnAa+oMD26xVvT857RAIuiY0bmsNF0g0dGlo GrWA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=s50PiUE0GZ0ZQQyDE7urYqyC+XXAehvlB01y0urqqec=; b=XlaQaIZOfvYhU9+4B0F0RhDc4Q9znwkxLHZNjzQrowBtNKMthgqZ+db284jDGUnQaA 0pAMq4EcE64L9Zggug1rhQNSTqXLpII1Tdz9wXTvGw1fY070b/7LfCcGvcgWBgl8iqdW oR3ZLqs2DcAk98e0Omx5k8Pjq+sLyYvyBIyzK9qX4jkRA5s7C5lITwCkeYZrlL/iUnfd VpLFeVlCFjW4L663CpT0JG4Je4ENXVNMQ2WyoAnt5/+wL2dGSOgjzFMkVJfbPbnJ/fA4 rmUSgOkYyTXsXNJ5KE6zaCdgcXF+rYUAR86qcy91aHFmyqeKebZrDt3jCk36SBogGSu3 C5FA== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=jHod2IEA; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id x22si1594043pll.257.2021.09.29.17.02.04; Wed, 29 Sep 2021 17:02:28 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=jHod2IEA; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347334AbhI2XgX (ORCPT + 99 others); Wed, 29 Sep 2021 19:36:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56764 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232554AbhI2XgX (ORCPT ); Wed, 29 Sep 2021 19:36:23 -0400 Received: from mail-pl1-x62c.google.com (mail-pl1-x62c.google.com [IPv6:2607:f8b0:4864:20::62c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 95ABEC06161C for ; Wed, 29 Sep 2021 16:34:41 -0700 (PDT) Received: by mail-pl1-x62c.google.com with SMTP id t4so2691343plo.0 for ; Wed, 29 Sep 2021 16:34:41 -0700 (PDT) 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=s50PiUE0GZ0ZQQyDE7urYqyC+XXAehvlB01y0urqqec=; b=jHod2IEAOYSVMk4eJ9KFe66IDNul71zOAQnH7GZhxrEAYN54b/WprrgAWaMqj8wppk 8PVbfnmuUnkaOZzQI2ceK0mpoApel9aQ8+U6aXrn+KimynTOOm9yJbupVhbBtY7U9mE3 ir91XMap1ANGFfr6e5w+czRSC3G48rSuncKp4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=s50PiUE0GZ0ZQQyDE7urYqyC+XXAehvlB01y0urqqec=; b=FpAg6S5APR33c90/G7B0P0Bd/d9yZzhpkgJfynWvCblvoZdgpBwiugiyQrHme0baek YsVySzNJZxzAjb9YmKruutFC4MRSSWSLIWIxzVgxYT5sj9HzBXRWJTkpA9BddUx1SNro iyZHK3ukcLOSFT7NQ5/p+absCRZCf8z7vupMyJ1OOadmP/5NVBFrFDCPs1J08ug7+hhq 9LBrwZ8Fpg74Eba+cO5nlGWtLeCyTiAwQvoYf2Z5sa4F+oJZFgm6VGYQ+Mdi8v7jP51B jQu63Tt6FvLRWPqtnpmGFfqUIBbsfgbTXZdm6weh6kLR0I++W4VMtQO8AaIvCFmgb7jk +ZyA== X-Gm-Message-State: AOAM531a/FBf7qZ7H9B91vYH6oqc1dG4pJeRjzaLDxfmZLgC/WywI7HE UYDndUPI6h8d6tIsQsA+DtCQ5w== X-Received: by 2002:a17:90a:a78f:: with SMTP id f15mr2783279pjq.106.1632958481050; Wed, 29 Sep 2021 16:34:41 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id v12sm631373pgt.94.2021.09.29.16.34.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 29 Sep 2021 16:34:40 -0700 (PDT) Date: Wed, 29 Sep 2021 16:34:39 -0700 From: Kees Cook To: Nick Alcock Cc: jeyu@kernel.org, masahiroy@kernel.org, linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org, arnd@arndb.de, eugene.loh@oracle.com, kris.van.hees@oracle.com Subject: Re: [PATCH v5] kallsyms: new /proc/kallmodsyms with builtin modules Message-ID: <202109291629.81106C83D@keescook> References: <20210929215154.300692-1-nick.alcock@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210929215154.300692-1-nick.alcock@oracle.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 29, 2021 at 10:51:47PM +0100, Nick Alcock wrote: > It would be useful if there were a mapping between kernel symbol and module > name that only changed when the kernel source code is changed. This mapping > should not change simply because a module becomes built into the kernel. > > It might also be useful if there were reliable symbol size information to > determine whether an address is within a symbol or outside it, especially > given that there could be huge gaps between symbols. This is a pretty cool series, but I'm left wondering "for what reason?" :) Perhaps I missed the specific rationale; there was a lot to run. ;) It would be useful, sure, but is there something that does, in fact, need this, or would like this if it were available? Since this provides a userspace API, what would be consuming that API? For example, when Syscall User Dispatch was added, it was clear it was for Wine[1]. -Kees [1] https://lore.kernel.org/lkml/160690190770.3364.5119373826178425644.tip-bot2@tip-bot2/ -- Kees Cook