From nobody Sun Apr 13 04:30:37 2025 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 1488314874152263.0655036125303; Tue, 28 Feb 2017 12:47:54 -0800 (PST) Received: from localhost ([::1]:36801 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cioga-0006MZ-Pf for importer@patchew.org; Tue, 28 Feb 2017 15:47:52 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45004) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cioWY-0005zA-Dc for qemu-devel@nongnu.org; Tue, 28 Feb 2017 15:37:33 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cioWX-0007om-IB for qemu-devel@nongnu.org; Tue, 28 Feb 2017 15:37:30 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60506) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cioWV-0007nW-9E; Tue, 28 Feb 2017 15:37:27 -0500 Received: from int-mx11.intmail.prod.int.phx2.redhat.com (int-mx11.intmail.prod.int.phx2.redhat.com [10.5.11.24]) (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 660854E328; Tue, 28 Feb 2017 20:37:27 +0000 (UTC) Received: from noname.redhat.com (ovpn-116-177.ams2.redhat.com [10.36.116.177]) by int-mx11.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v1SKapFJ021888; Tue, 28 Feb 2017 15:37:25 -0500 From: Kevin Wolf To: qemu-block@nongnu.org Date: Tue, 28 Feb 2017 21:36:17 +0100 Message-Id: <1488314205-16264-19-git-send-email-kwolf@redhat.com> In-Reply-To: <1488314205-16264-1-git-send-email-kwolf@redhat.com> References: <1488314205-16264-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.24 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Tue, 28 Feb 2017 20:37:27 +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] [PULL 18/46] block: Request real permissions in blk_new_open() 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, qemu-devel@nongnu.org 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" We can figure out the necessary permissions from the flags that the caller passed. Signed-off-by: Kevin Wolf Reviewed-by: Max Reitz Acked-by: Fam Zheng --- block/block-backend.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/block/block-backend.c b/block/block-backend.c index 299948f..03d5495 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -166,17 +166,33 @@ BlockBackend *blk_new_open(const char *filename, cons= t char *reference, { BlockBackend *blk; BlockDriverState *bs; + uint64_t perm; + + /* blk_new_open() is mainly used in .bdrv_create implementations and t= he + * tools where sharing isn't a concern because the BDS stays private, = so we + * just request permission according to the flags. + * + * The exceptions are xen_disk and blockdev_init(); in these cases, the + * caller of blk_new_open() doesn't make use of the permissions, but t= hey + * shouldn't hurt either. We can still share everything here because t= he + * guest devices will add their own blockers if they can't share. */ + perm =3D BLK_PERM_CONSISTENT_READ; + if (flags & BDRV_O_RDWR) { + perm |=3D BLK_PERM_WRITE; + } + if (flags & BDRV_O_RESIZE) { + perm |=3D BLK_PERM_RESIZE; + } =20 - blk =3D blk_new(0, BLK_PERM_ALL); + blk =3D blk_new(perm, BLK_PERM_ALL); bs =3D bdrv_open(filename, reference, options, flags, errp); if (!bs) { blk_unref(blk); return NULL; } =20 - /* FIXME Use real permissions */ blk->root =3D bdrv_root_attach_child(bs, "root", &child_root, - 0, BLK_PERM_ALL, blk, &error_abort); + perm, BLK_PERM_ALL, blk, &error_abo= rt); =20 return blk; } --=20 1.8.3.1