From nobody Mon Feb 9 11:28:49 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 1490051536894188.17677488514187; Mon, 20 Mar 2017 16:12:16 -0700 (PDT) Received: from localhost ([::1]:35472 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cq6TH-0003Iw-Gw for importer@patchew.org; Mon, 20 Mar 2017 19:12:15 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40377) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cq6QW-0001R0-DX for qemu-devel@nongnu.org; Mon, 20 Mar 2017 19:09:26 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cq6QS-0004iW-RL for qemu-devel@nongnu.org; Mon, 20 Mar 2017 19:09:24 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:38444 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 1cq6QS-0004hZ-KJ for qemu-devel@nongnu.org; Mon, 20 Mar 2017 19:09:20 -0400 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v2KN8XrJ014374 for ; Mon, 20 Mar 2017 19:09:20 -0400 Received: from e37.co.us.ibm.com (e37.co.us.ibm.com [32.97.110.158]) by mx0b-001b2d01.pphosted.com with ESMTP id 29af6evvke-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 20 Mar 2017 19:09:20 -0400 Received: from localhost by e37.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Mon, 20 Mar 2017 17:09:16 -0600 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v2KN9FdO16974180; Mon, 20 Mar 2017 16:09:15 -0700 Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 76D94136043; Mon, 20 Mar 2017 17:09:15 -0600 (MDT) Received: from localhost (unknown [9.53.92.194]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP id 61AEB136048; Mon, 20 Mar 2017 17:09:15 -0600 (MDT) From: Michael Roth To: qemu-devel@nongnu.org Date: Mon, 20 Mar 2017 18:07:38 -0500 X-Mailer: git-send-email 2.7.4 In-Reply-To: <1490051325-3770-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1490051325-3770-1-git-send-email-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 17032023-0024-0000-0000-00001617D574 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006819; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000206; SDB=6.00836553; UDB=6.00411161; IPR=6.00614321; BA=6.00005224; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00014732; XFM=3.00000013; UTC=2017-03-20 23:09:17 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17032023-0025-0000-0000-0000499B6D4F Message-Id: <1490051325-3770-15-git-send-email-mdroth@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2017-03-20_16:, , 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=8.0.1-1702020001 definitions=main-1703200196 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 14/81] 9pfs: local: statfs: don't follow symlinks 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: Greg Kurz , qemu-stable@nongnu.org, 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" From: Greg Kurz The local_statfs() callback is vulnerable to symlink attacks because it calls statfs() which follows symbolic links in all path elements. This patch converts local_statfs() to rely on open_nofollow() and fstatfs() instead. This partly fixes CVE-2016-9602. Signed-off-by: Greg Kurz Reviewed-by: Stefan Hajnoczi (cherry picked from commit 31e51d1c15b35dc98b88a301812914b70a2b55dc) Signed-off-by: Greg Kurz Signed-off-by: Michael Roth --- hw/9pfs/9p-local.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index fa1477f..80b3964 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -1078,13 +1078,11 @@ static int local_fsync(FsContext *ctx, int fid_type, =20 static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *st= buf) { - char *buffer; - int ret; - char *path =3D fs_path->data; + int fd, ret; =20 - buffer =3D rpath(s, path); - ret =3D statfs(buffer, stbuf); - g_free(buffer); + fd =3D local_open_nofollow(s, fs_path->data, O_RDONLY, 0); + ret =3D fstatfs(fd, stbuf); + close_preserve_errno(fd); return ret; } =20 --=20 2.7.4