From nobody Mon Feb 9 20:58:48 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1487009203763760.0873780412549; Mon, 13 Feb 2017 10:06:43 -0800 (PST) Received: from localhost ([::1]:58602 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cdL1O-0001H4-Bs for importer@patchew.org; Mon, 13 Feb 2017 13:06:42 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59919) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cdKMZ-00042V-GE for qemu-devel@nongnu.org; Mon, 13 Feb 2017 12:24:32 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cdKMY-0006TI-2i for qemu-devel@nongnu.org; Mon, 13 Feb 2017 12:24:31 -0500 Received: from mx1.redhat.com ([209.132.183.28]:40504) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cdKMV-0006SQ-Bx; Mon, 13 Feb 2017 12:24:27 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8CFD3C0567A3; Mon, 13 Feb 2017 17:24:27 +0000 (UTC) Received: from noname.redhat.com (ovpn-117-183.ams2.redhat.com [10.36.117.183]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1DHNC3s031842; Mon, 13 Feb 2017 12:24:25 -0500 From: Kevin Wolf To: qemu-block@nongnu.org Date: Mon, 13 Feb 2017 18:23:00 +0100 Message-Id: <1487006583-24350-39-git-send-email-kwolf@redhat.com> In-Reply-To: <1487006583-24350-1-git-send-email-kwolf@redhat.com> References: <1487006583-24350-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.32]); Mon, 13 Feb 2017 17:24:27 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC PATCH 38/41] nbd/server: Use real permissions for NBD exports X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, jcody@redhat.com, famz@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" NBD can't cope with device size changes, so resize must be forbidden, but otherwise we can tolerate anything. Depending on whether the export is writable or not, we only require consistent reads and writes. Signed-off-by: Kevin Wolf --- nbd/server.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/nbd/server.c b/nbd/server.c index deb4358..4bb37d6 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -889,10 +889,17 @@ NBDExport *nbd_export_new(BlockDriverState *bs, off_t= dev_offset, off_t size, { BlockBackend *blk; NBDExport *exp =3D g_malloc0(sizeof(NBDExport)); + uint64_t perm; int ret; =20 - /* FIXME Use real permissions */ - blk =3D blk_new(0, BLK_PERM_ALL); + /* Don't allow resize while the NBD server is running, otherwise we do= n't + * care what happens with the node. */ + perm =3D BLK_PERM_CONSISTENT_READ; + if ((nbdflags & NBD_FLAG_READ_ONLY) =3D=3D 0) { + perm |=3D BLK_PERM_WRITE; + } + blk =3D blk_new(perm, BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHAN= GED | + BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD); ret =3D blk_insert_bs(blk, bs, errp); if (ret < 0) { goto fail; --=20 1.8.3.1