From patchwork Mon Dec 7 16:32:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miklos Szeredi X-Patchwork-Id: 11956367 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 6202CC3526C for ; Mon, 7 Dec 2020 16:35:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A674238E7 for ; Mon, 7 Dec 2020 16:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727834AbgLGQeo (ORCPT ); Mon, 7 Dec 2020 11:34:44 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42404 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727811AbgLGQem (ORCPT ); Mon, 7 Dec 2020 11:34:42 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1607358796; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RE0m3vgq1/OaRAwZjvKOK2ey/mE38mR/q+wtN6wib9s=; b=Eg87k5igU07VVyU7gpntFf3poClRUjMOlw7v0GBPEorMtynYOXsofThHhUeLdb1V6DxNjI /JLlV88aynvZQ5Dc5aj3pw0U1aLb3J69TrXmEQScAGoinIL6+JScwpbTn+6XSdKges5l1t DaAC9Bu+/wJggHOT4WG4Ej477iq1RCQ= Received: from mail-ed1-f69.google.com (mail-ed1-f69.google.com [209.85.208.69]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-103-45VGdHYhNlm5LXG75mpyHg-1; Mon, 07 Dec 2020 11:33:14 -0500 X-MC-Unique: 45VGdHYhNlm5LXG75mpyHg-1 Received: by mail-ed1-f69.google.com with SMTP id g8so6030036edm.7 for ; Mon, 07 Dec 2020 08:33:14 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=RE0m3vgq1/OaRAwZjvKOK2ey/mE38mR/q+wtN6wib9s=; b=g8Fv8r9R7mifCAV1mKrlhJS4FFgna4NBEoj8fZFik0U8c8/dVhWbQV9V6RgTNG0o8E ef5jt2zI+QcobVFLBKPU+AOTMR2X6NXB3BWs1iy/SqU+g6QwCFMNQe0FAugEx2y51meG mjRIe1TvvuZb7b0MCKZAnPENZYnwEJ+zZaOr7fr3mu0aS70Q/bk9RtT46//K5YVM0gaR HO+lotei1S4tb5gVSfVT7HCMJ6OC3x8FPUySPfTAxXs7KDg7NePMgz9Q3+cotqBTezap B6jryZHApyuHe7OL5vh5BzliGcK8BvgjiVGYaqbipVpF8c7y8xX5i0Jrm0V5sMqueOcr 6PLA== X-Gm-Message-State: AOAM531BnDXxgxEcLU5CDcV+I0lD8clFiy8iTDOmThLZERoS1f72zgxL 9ucsRn9rNXuBhudi6bdVCBwgP8zZ3Zsai6CPn4XNITDEr55Z4pivUvSSB3wlsAXug/eT433B4iU oza9oZK1UiQjaDXaKFpsXGa77HQ== X-Received: by 2002:a50:d74c:: with SMTP id i12mr20512779edj.236.1607358793439; Mon, 07 Dec 2020 08:33:13 -0800 (PST) X-Google-Smtp-Source: ABdhPJzZo9cLo2B/sr3LytBzOfhCP7NvepbgDDGPqp8OuSqAKVtWfqlfy6nWwFOViRsEnP4mLzJm9A== X-Received: by 2002:a50:d74c:: with SMTP id i12mr20512764edj.236.1607358793260; Mon, 07 Dec 2020 08:33:13 -0800 (PST) Received: from miu.piliscsaba.redhat.com (catv-86-101-169-67.catv.broadband.hu. [86.101.169.67]) by smtp.gmail.com with ESMTPSA id op5sm12801964ejb.43.2020.12.07.08.33.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 07 Dec 2020 08:33:12 -0800 (PST) From: Miklos Szeredi To: "Eric W . Biederman" Cc: linux-fsdevel@vger.kernel.org, linux-unionfs@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 10/10] ovl: unprivieged mounts Date: Mon, 7 Dec 2020 17:32:55 +0100 Message-Id: <20201207163255.564116-11-mszeredi@redhat.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201207163255.564116-1-mszeredi@redhat.com> References: <20201207163255.564116-1-mszeredi@redhat.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Enable unprivileged user namespace mounts of overlayfs. Overlayfs's permission model (*) ensures that the mounter itself cannot gain additional privileges by the act of creating an overlayfs mount. This feature request is coming from the "rootless" container crowd. (*) Documentation/filesystems/overlayfs.txt#Permission model Signed-off-by: Miklos Szeredi --- fs/overlayfs/super.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c index 189380b946be..019e6f1834b0 100644 --- a/fs/overlayfs/super.c +++ b/fs/overlayfs/super.c @@ -2073,6 +2073,7 @@ static struct dentry *ovl_mount(struct file_system_type *fs_type, int flags, static struct file_system_type ovl_fs_type = { .owner = THIS_MODULE, .name = "overlay", + .fs_flags = FS_USERNS_MOUNT, .mount = ovl_mount, .kill_sb = kill_anon_super, };