From nobody Mon Feb 9 22:38:22 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 1498744377496250.41681857634433; Thu, 29 Jun 2017 06:52:57 -0700 (PDT) Received: from localhost ([::1]:39499 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQZsO-0002dS-6C for importer@patchew.org; Thu, 29 Jun 2017 09:52:56 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:55039) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dQZkK-0003QZ-Tg for qemu-devel@nongnu.org; Thu, 29 Jun 2017 09:44:41 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dQZkG-0002xh-1K for qemu-devel@nongnu.org; Thu, 29 Jun 2017 09:44:36 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37002 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 1dQZkF-0002xG-Ro for qemu-devel@nongnu.org; Thu, 29 Jun 2017 09:44:31 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v5TDcuNY111243 for ; Thu, 29 Jun 2017 09:44:31 -0400 Received: from e06smtp14.uk.ibm.com (e06smtp14.uk.ibm.com [195.75.94.110]) by mx0a-001b2d01.pphosted.com with ESMTP id 2bd1mfka6h-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 29 Jun 2017 09:44:30 -0400 Received: from localhost by e06smtp14.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Thu, 29 Jun 2017 14:44:26 +0100 Received: from d06av24.portsmouth.uk.ibm.com (d06av24.portsmouth.uk.ibm.com [9.149.105.60]) by b06cxnps4075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v5TDiQea29425740; Thu, 29 Jun 2017 13:44:26 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0ACB542047; Thu, 29 Jun 2017 14:42:02 +0100 (BST) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id ECD204203F; Thu, 29 Jun 2017 14:42:01 +0100 (BST) Received: from smtp.lab.toulouse-stg.fr.ibm.com (unknown [9.101.4.1]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 29 Jun 2017 14:42:01 +0100 (BST) Received: from bahia.lan (icon-9-164-130-68.megacenter.de.ibm.com [9.164.130.68]) by smtp.lab.toulouse-stg.fr.ibm.com (Postfix) with ESMTP id 783BC220144; Thu, 29 Jun 2017 15:44:25 +0200 (CEST) From: Greg Kurz To: qemu-devel@nongnu.org Date: Thu, 29 Jun 2017 15:43:51 +0200 X-Mailer: git-send-email 2.7.5 In-Reply-To: <1498743831-28676-1-git-send-email-groug@kaod.org> References: <1498743831-28676-1-git-send-email-groug@kaod.org> X-TM-AS-GCONF: 00 x-cbid: 17062913-0016-0000-0000-000004CA6625 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17062913-0017-0000-0000-000027FD661D Message-Id: <1498743831-28676-9-git-send-email-groug@kaod.org> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-06-29_09:, , 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=8.0.1-1703280000 definitions=main-1706290224 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 8/8] 9pfs: handle transport errors in pdu_complete() 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 , Greg Kurz 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" Contrary to what is written in the comment, a buggy guest can misconfigure the transport buffers and pdu_marshal() may return an error. If this ever happens, it is up to the transport layer to handle the situation (9P is transport agnostic). This fixes Coverity issue CID1348518. Signed-off-by: Greg Kurz Reviewed-by: Stefano Stabellini --- hw/9pfs/9p.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 8e5cac71eb60..6c92bad5b3b4 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -624,15 +624,11 @@ void pdu_free(V9fsPDU *pdu) QLIST_INSERT_HEAD(&s->free_list, pdu, next); } =20 -/* - * We don't do error checking for pdu_marshal/unmarshal here - * because we always expect to have enough space to encode - * error details - */ static void coroutine_fn pdu_complete(V9fsPDU *pdu, ssize_t len) { int8_t id =3D pdu->id + 1; /* Response */ V9fsState *s =3D pdu->s; + int ret; =20 if (len < 0) { int err =3D -len; @@ -644,11 +640,19 @@ static void coroutine_fn pdu_complete(V9fsPDU *pdu, s= size_t len) str.data =3D strerror(err); str.size =3D strlen(str.data); =20 - len +=3D pdu_marshal(pdu, len, "s", &str); + ret =3D pdu_marshal(pdu, len, "s", &str); + if (ret < 0) { + goto out_notify; + } + len +=3D ret; id =3D P9_RERROR; } =20 - len +=3D pdu_marshal(pdu, len, "d", err); + ret =3D pdu_marshal(pdu, len, "d", err); + if (ret < 0) { + goto out_notify; + } + len +=3D ret; =20 if (s->proto_version =3D=3D V9FS_PROTO_2000L) { id =3D P9_RLERROR; @@ -657,12 +661,15 @@ static void coroutine_fn pdu_complete(V9fsPDU *pdu, s= size_t len) } =20 /* fill out the header */ - pdu_marshal(pdu, 0, "dbw", (int32_t)len, id, pdu->tag); + if (pdu_marshal(pdu, 0, "dbw", (int32_t)len, id, pdu->tag) < 0) { + goto out_notify; + } =20 /* keep these in sync */ pdu->size =3D len; pdu->id =3D id; =20 +out_notify: pdu->s->transport->push_and_notify(pdu); =20 /* Now wakeup anybody waiting in flush for this request */ --=20 2.7.5