Received: by 2002:a25:8b91:0:0:0:0:0 with SMTP id j17csp13819496ybl; Sun, 29 Dec 2019 21:45:43 -0800 (PST) X-Google-Smtp-Source: APXvYqwg2YlyaQjN7xMKov4MnFUxDTLRlbU4H9wQGhwDctJaThXKt8VSKb3InBBTpoCPFiDjklNL X-Received: by 2002:a9d:588c:: with SMTP id x12mr70107655otg.2.1577684743124; Sun, 29 Dec 2019 21:45:43 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1577684743; cv=none; d=google.com; s=arc-20160816; b=y+ETGChuGNaQ+84qcwcNy5gjUpSGC2NzVeuhe2nDwKBeYw3HGvHYZ6rKqIvlQ6g4XO aG+HXsSGvALHems/v9cJ+pLDdE84WPto4A/zeTh+u/U/lbyUrgbRnWWpvRgEGj+b8bPb 306mN9S2jZXucmslEPbttKck24be66p6EtGd8csGtvAb+RbELArZ8E1GwTG5g68Fk8qN TK0ZueWrQtyPdEyL+O6CsBgWwMokBCpMy49Is7GRgqgr0mev8yGYtE7bfqzxJsQjq5MU L0D6Q/EXLolt2EyGYXHJiDJuHDT7oT3hwqnZ51uob4boO4zg97HxcIYoF4Qlk46zjYzq B3Dg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:user-agent:in-reply-to :content-disposition:mime-version:references:message-id:subject:cc :to:from:date; bh=Gp1YOvHbyxbAiXEgQEjS5ksiKgEuma3iGT+OhioXfgs=; b=uQCL0DG2gUBDh1Scpj0PBKv4NmVI2Qj0f1Xc6+vFm3ZiNjin1bz7r3aN2zZ7b4EpaE MCo5vUyy9G7mzpHHFDOtXyv316yB0SVZjFThFgPdgCV1I4nMxxA53kf8+wRhQ2DptFTV 4jzAM8UBYDVy7J6i5pAtN4LgqrxJqrBQH/hz/PFnVWJPOsbrmZZE3i8xAuDU81TtNshN V/1nE4+y8gYmJuh+2A+T++QwkVV/CEP33u4PwROOHvQ83cCpaSJFVlHAZBDf8RBFWWxI 6vM/C39lVwGlU0Gi2FnlUj2HF7Xef17CiFUtlAbSlaTMctRGwEBvfhczKHm0AucUEAh1 REQw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id m90si21615029otc.259.2019.12.29.21.45.27; Sun, 29 Dec 2019 21:45:43 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727150AbfL3Foa (ORCPT + 99 others); Mon, 30 Dec 2019 00:44:30 -0500 Received: from zeniv.linux.org.uk ([195.92.253.2]:42590 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725834AbfL3Foa (ORCPT ); Mon, 30 Dec 2019 00:44:30 -0500 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1ilnqf-0005Om-SW; Mon, 30 Dec 2019 05:44:14 +0000 Date: Mon, 30 Dec 2019 05:44:13 +0000 From: Al Viro To: Aleksa Sarai Cc: David Howells , Eric Biederman , Linus Torvalds , stable@vger.kernel.org, Christian Brauner , Serge Hallyn , dev@opencontainers.org, containers@lists.linux-foundation.org, linux-api@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC 0/1] mount: universally disallow mounting over symlinks Message-ID: <20191230054413.GX4203@ZenIV.linux.org.uk> References: <20191230052036.8765-1-cyphar@cyphar.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191230052036.8765-1-cyphar@cyphar.com> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 30, 2019 at 04:20:35PM +1100, Aleksa Sarai wrote: > A reasonably detailed explanation of the issues is provided in the patch > itself, but the full traces produced by both the oopses and deadlocks is > included below (it makes little sense to include them in the commit since we > are disabling this feature, not directly fixing the bugs themselves). > > I've posted this as an RFC on whether this feature should be allowed at > all (and if anyone knows of legitimate uses for it), or if we should > work on fixing these other kernel bugs that it exposes. Umm... Are all of those traces a) reproducible on mainline and b) reproducible as the first oopsen? As it is, quite a few might be secondary results of earlier memory corruption...