From patchwork Wed Sep 20 13:50:38 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kurz X-Patchwork-Id: 816279 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3xy2p225Ltz9sPt for ; Thu, 21 Sep 2017 00:54:34 +1000 (AEST) Received: from localhost ([::1]:48622 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dugOW-0006n6-Be for incoming@patchwork.ozlabs.org; Wed, 20 Sep 2017 10:54:32 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49105) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dufP5-0006Wm-Ew for qemu-devel@nongnu.org; Wed, 20 Sep 2017 09:51:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dufP2-0004Ga-Cr for qemu-devel@nongnu.org; Wed, 20 Sep 2017 09:51:03 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:43329 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 1dufP2-0004GH-75 for qemu-devel@nongnu.org; Wed, 20 Sep 2017 09:51:00 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v8KDn9NB071904 for ; Wed, 20 Sep 2017 09:50:59 -0400 Received: from e06smtp11.uk.ibm.com (e06smtp11.uk.ibm.com [195.75.94.107]) by mx0b-001b2d01.pphosted.com with ESMTP id 2d3nqrgdf3-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 20 Sep 2017 09:50:59 -0400 Received: from localhost by e06smtp11.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 20 Sep 2017 14:50:55 +0100 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v8KDosCm20316374; Wed, 20 Sep 2017 13:50:54 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 93F4EA4051; Wed, 20 Sep 2017 14:46:55 +0100 (BST) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 81A1EA404D; Wed, 20 Sep 2017 14:46:55 +0100 (BST) Received: from smtp.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.1]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 20 Sep 2017 14:46:55 +0100 (BST) Received: from bahia.lan (icon-9-167-240-87.megacenter.de.ibm.com [9.167.240.87]) by smtp.lab.toulouse-stg.fr.ibm.com (Postfix) with ESMTP id E5BBB220154; Wed, 20 Sep 2017 15:50:53 +0200 (CEST) From: Greg Kurz To: qemu-devel@nongnu.org Date: Wed, 20 Sep 2017 15:50:38 +0200 X-Mailer: git-send-email 2.13.5 In-Reply-To: <20170920135038.21058-1-groug@kaod.org> References: <20170920135038.21058-1-groug@kaod.org> X-TM-AS-GCONF: 00 x-cbid: 17092013-0040-0000-0000-000003FBAD1B X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17092013-0041-0000-0000-0000209CE3F4 Message-Id: <20170920135038.21058-4-groug@kaod.org> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-09-20_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=13 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1707230000 definitions=main-1709200189 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] [fuzzy] X-Received-From: 148.163.158.5 Subject: [Qemu-devel] [PULL 3/3] 9pfs: check the size of transport buffer before marshaling 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: Peter Maydell , Jan Dakinevich , Greg Kurz Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Jan Dakinevich v9fs_do_readdir_with_stat() should check for a maximum buffer size before an attempt to marshal gathered data. Otherwise, buffers assumed as misconfigured and the transport would be broken. The patch brings v9fs_do_readdir_with_stat() in conformity with v9fs_do_readdir() behavior. Signed-off-by: Jan Dakinevich [groug, regression caused my commit 8d37de41cab1 # 2.10] Signed-off-by: Greg Kurz --- hw/9pfs/9p.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index cdd44bdc82ef..23ac7bb532f0 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -1748,17 +1748,26 @@ static int coroutine_fn v9fs_do_readdir_with_stat(V9fsPDU *pdu, if (err < 0) { break; } + if ((count + v9stat.size + 2) > max_count) { + v9fs_readdir_unlock(&fidp->fs.dir); + + /* Ran out of buffer. Set dir back to old position and return */ + v9fs_co_seekdir(pdu, fidp, saved_dir_pos); + v9fs_stat_free(&v9stat); + v9fs_path_free(&path); + return count; + } + /* 11 = 7 + 4 (7 = start offset, 4 = space for storing count) */ len = pdu_marshal(pdu, 11 + count, "S", &v9stat); v9fs_readdir_unlock(&fidp->fs.dir); - if ((len != (v9stat.size + 2)) || ((count + len) > max_count)) { - /* Ran out of buffer. Set dir back to old position and return */ + if (len < 0) { v9fs_co_seekdir(pdu, fidp, saved_dir_pos); v9fs_stat_free(&v9stat); v9fs_path_free(&path); - return count; + return len; } count += len; v9fs_stat_free(&v9stat);