From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45939) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bkxUQ-0002If-LB for qemu-devel@nongnu.org; Fri, 16 Sep 2016 14:03:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bkxUN-000089-Aw for qemu-devel@nongnu.org; Fri, 16 Sep 2016 14:03:54 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:58405) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bkxUN-00007s-22 for qemu-devel@nongnu.org; Fri, 16 Sep 2016 14:03:51 -0400 Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8GI3Wgi094184 for ; Fri, 16 Sep 2016 14:03:50 -0400 Received: from e06smtp06.uk.ibm.com (e06smtp06.uk.ibm.com [195.75.94.102]) by mx0a-001b2d01.pphosted.com with ESMTP id 25fk2yskpa-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Fri, 16 Sep 2016 14:03:49 -0400 Received: from localhost by e06smtp06.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 16 Sep 2016 19:03:47 +0100 Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by d06dlp03.portsmouth.uk.ibm.com (Postfix) with ESMTP id E7CA51B0805F for ; Fri, 16 Sep 2016 19:05:33 +0100 (BST) Received: from d06av10.portsmouth.uk.ibm.com (d06av10.portsmouth.uk.ibm.com [9.149.37.251]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u8GI3iQk16843054 for ; Fri, 16 Sep 2016 18:03:44 GMT Received: from d06av10.portsmouth.uk.ibm.com (localhost [127.0.0.1]) by d06av10.portsmouth.uk.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u8GH3jvQ019658 for ; Fri, 16 Sep 2016 11:03:45 -0600 From: Greg Kurz Date: Fri, 16 Sep 2016 20:03:30 +0200 In-Reply-To: <1474049010-13533-1-git-send-email-groug@kaod.org> References: <1474049010-13533-1-git-send-email-groug@kaod.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Message-Id: <1474049010-13533-9-git-send-email-groug@kaod.org> Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [PULL v2 8/8] 9pfs: fix potential segfault during walk List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , "Aneesh Kumar K.V" , Greg Kurz If the call to fid_to_qid() returns an error, we will call v9fs_path_free= () on uninitialized paths. It is a regression introduced by the following commit: 56f101ecce0e 9pfs: handle walk of ".." in the root directory Let's fix this by initializing dpath and path before calling fid_to_qid(). Signed-off-by: Greg Kurz Reviewed-by: C=C3=A9dric Le Goater [groug: updated the changelog to indicate this is regression and to provi= de the offending commit SHA1] Signed-off-by: Greg Kurz --- hw/9pfs/9p.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 639f93930285..119ee584969b 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -1333,13 +1333,14 @@ static void v9fs_walk(void *opaque) goto out_nofid; } =20 + v9fs_path_init(&dpath); + v9fs_path_init(&path); + err =3D fid_to_qid(pdu, fidp, &qid); if (err < 0) { goto out; } =20 - v9fs_path_init(&dpath); - v9fs_path_init(&path); /* * Both dpath and path initially poin to fidp. * Needed to handle request with nwnames =3D=3D 0 --=20 2.5.5