From patchwork Tue Aug 29 00:13:45 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 9926463 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 A91F860380 for ; Tue, 29 Aug 2017 00:17:24 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9A99F287BF for ; Tue, 29 Aug 2017 00:17:24 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8E4A0287C5; Tue, 29 Aug 2017 00:17:24 +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 E4764287BF for ; Tue, 29 Aug 2017 00:17:23 +0000 (UTC) Received: from localhost ([::1]:41876 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUDb-0000sT-0v for patchwork-qemu-devel@patchwork.kernel.org; Mon, 28 Aug 2017 20:17:23 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:47244) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmUC3-0000oo-6K for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmUBz-00052H-W7 for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:47 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:40825 helo=mx0a-001b2d01.pphosted.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmUBz-00051Z-Q8 for qemu-devel@nongnu.org; Mon, 28 Aug 2017 20:15:43 -0400 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7T0EEWB019727 for ; Mon, 28 Aug 2017 20:15:42 -0400 Received: from e32.co.us.ibm.com (e32.co.us.ibm.com [32.97.110.150]) by mx0b-001b2d01.pphosted.com with ESMTP id 2cmsfn2vqc-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 28 Aug 2017 20:15:41 -0400 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Mon, 28 Aug 2017 18:15:39 -0600 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v7T0FcMM852374; Mon, 28 Aug 2017 17:15:39 -0700 Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id D7EEEC603C; Mon, 28 Aug 2017 18:15:38 -0600 (MDT) Received: from localhost (unknown [9.80.85.217]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP id A438CC6042; Mon, 28 Aug 2017 18:15:38 -0600 (MDT) From: Michael Roth To: qemu-devel@nongnu.org Date: Mon, 28 Aug 2017 19:13:45 -0500 X-Mailer: git-send-email 2.7.4 In-Reply-To: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1503965694-10794-1-git-send-email-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17082900-0004-0000-0000-000012D6D507 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007630; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000226; SDB=6.00909027; UDB=6.00455849; IPR=6.00689279; BA=6.00005557; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016909; XFM=3.00000015; UTC=2017-08-29 00:15:40 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17082900-0005-0000-0000-000080E59E37 Message-Id: <1503965694-10794-11-git-send-email-mdroth@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-08-28_13:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=3 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1708290001 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PATCH 10/79] block: Do not unref bs->file on error in BD's 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: Kevin Wolf , qemu-stable@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Max Reitz The block layer takes care of removing the bs->file child if the block driver's bdrv_open()/bdrv_file_open() implementation fails. The block driver therefore does not need to do so, and indeed should not unless it sets bs->file to NULL afterwards -- because if this is not done, the bdrv_unref_child() in bdrv_open_inherit() will dereference the freed memory block at bs->file afterwards, which is not good. We can now decide whether to add a "bs->file = NULL;" after each of the offending bdrv_unref_child() invocations, or just drop them altogether. The latter is simpler, so let's do that. Cc: qemu-stable Signed-off-by: Max Reitz Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf (cherry picked from commit de234897b60e034ba94b307fc289e2dc692c9251) Signed-off-by: Michael Roth --- block/blkdebug.c | 4 +--- block/blkreplay.c | 3 --- block/blkverify.c | 3 --- 3 files changed, 1 insertion(+), 9 deletions(-) diff --git a/block/blkdebug.c b/block/blkdebug.c index 67e8024..cc4a146 100644 --- a/block/blkdebug.c +++ b/block/blkdebug.c @@ -389,14 +389,12 @@ static int blkdebug_open(BlockDriverState *bs, QDict *options, int flags, } else if (align) { error_setg(errp, "Invalid alignment"); ret = -EINVAL; - goto fail_unref; + goto out; } ret = 0; goto out; -fail_unref: - bdrv_unref_child(bs, bs->file); out: if (ret < 0) { g_free(s->config_file); diff --git a/block/blkreplay.c b/block/blkreplay.c index e110211..6aa5fd4 100755 --- a/block/blkreplay.c +++ b/block/blkreplay.c @@ -37,9 +37,6 @@ static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags, ret = 0; fail: - if (ret < 0) { - bdrv_unref_child(bs, bs->file); - } return ret; } diff --git a/block/blkverify.c b/block/blkverify.c index 9a1e21c..af23281 100644 --- a/block/blkverify.c +++ b/block/blkverify.c @@ -142,9 +142,6 @@ static int blkverify_open(BlockDriverState *bs, QDict *options, int flags, ret = 0; fail: - if (ret < 0) { - bdrv_unref_child(bs, bs->file); - } qemu_opts_del(opts); return ret; }