From patchwork Wed Jan 25 17:22:02 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Cody X-Patchwork-Id: 9537507 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B1DC56046A for ; Wed, 25 Jan 2017 17:23:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A2CDD281B7 for ; Wed, 25 Jan 2017 17:23:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 97B3C28304; Wed, 25 Jan 2017 17:23:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2A5B2281B7 for ; Wed, 25 Jan 2017 17:23:05 +0000 (UTC) Received: from localhost ([::1]:33288 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cWRHj-0004wP-Kc for patchwork-qemu-devel@patchwork.kernel.org; Wed, 25 Jan 2017 12:23:03 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38345) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cWRGt-0004bH-GU for qemu-devel@nongnu.org; Wed, 25 Jan 2017 12:22:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cWRGn-0007BQ-4X for qemu-devel@nongnu.org; Wed, 25 Jan 2017 12:22:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56966) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cWRGm-0007BH-Vi for qemu-devel@nongnu.org; Wed, 25 Jan 2017 12:22:05 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) (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 58ED1624DB for ; Wed, 25 Jan 2017 17:22:04 +0000 (UTC) Received: from localhost (ovpn-116-248.phx2.redhat.com [10.3.116.248]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id v0PHM3H1025255 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 25 Jan 2017 12:22:03 -0500 From: Jeff Cody To: qemu-devel@nongnu.org Date: Wed, 25 Jan 2017 12:22:02 -0500 Message-Id: <9a93d47ddba5f86d36cbdf884d86e2fa6f5542ae.1485364872.git.jcody@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 25 Jan 2017 17:22:04 +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] [PATCH 1/1] block: check full backing filename when searching protocol filenames 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, mreitz@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP In bdrv_find_backing_image(), if we are searching an image for a backing file that contains a protocol, we currently only compare unmodified paths. However, some management software will change the backing filename to be a relative filename in a path. QEMU is able to handle this fine, because internally it will use path_combine to put together the full protocol URI. However, this can lead to an inability to match an image during a QAPI command that needs to use bdrv_find_backing_image() to find the image, when it is searched by the full URI. When searching for a protocol filename, if the straight comparison fails, this patch will also compare against the full backing filename to see if that is a match. Signed-off-by: Jeff Cody Reviewed-by: Eric Blake --- block.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/block.c b/block.c index 39ddea3..a173afc 100644 --- a/block.c +++ b/block.c @@ -3145,6 +3145,7 @@ BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, int is_protocol = 0; BlockDriverState *curr_bs = NULL; BlockDriverState *retval = NULL; + Error *local_error = NULL; if (!bs || !bs->drv || !backing_file) { return NULL; @@ -3165,6 +3166,17 @@ BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, retval = curr_bs->backing->bs; break; } + /* Also check against the full backing filename for the image */ + bdrv_get_full_backing_filename(curr_bs, backing_file_full, PATH_MAX, + &local_error); + if (local_error == NULL) { + if (strcmp(backing_file, backing_file_full) == 0) { + retval = curr_bs->backing->bs; + break; + } + } else { + error_free(local_error); + } } else { /* If not an absolute filename path, make it relative to the current * image's filename path */