From patchwork Tue Apr 5 05:56:11 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Harsh Prateek Bora X-Patchwork-Id: 89769 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id E7D0AB6F7A for ; Tue, 5 Apr 2011 15:58:12 +1000 (EST) Received: from localhost ([127.0.0.1]:52571 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q6zHF-0001Fu-CL for incoming@patchwork.ozlabs.org; Tue, 05 Apr 2011 01:58:09 -0400 Received: from [140.186.70.92] (port=40722 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Q6zFX-0001E8-UY for qemu-devel@nongnu.org; Tue, 05 Apr 2011 01:56:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Q6zFW-0006p2-Ed for qemu-devel@nongnu.org; Tue, 05 Apr 2011 01:56:23 -0400 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:53250) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Q6zFV-0006oA-Uf for qemu-devel@nongnu.org; Tue, 05 Apr 2011 01:56:22 -0400 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [202.81.31.245]) by e23smtp03.au.ibm.com (8.14.4/8.13.1) with ESMTP id p355pXlM008928 for ; Tue, 5 Apr 2011 15:51:33 +1000 Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p355uGm41859662 for ; Tue, 5 Apr 2011 15:56:16 +1000 Received: from d23av03.au.ibm.com (loopback [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p355uG7X018429 for ; Tue, 5 Apr 2011 15:56:16 +1000 Received: from harshbora.in.ibm.com ([9.124.210.193]) by d23av03.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p355uDWW018355; Tue, 5 Apr 2011 15:56:14 +1000 From: Harsh Prateek Bora To: qemu-devel@nongnu.org, stefanha@gmail.com Date: Tue, 5 Apr 2011 11:26:11 +0530 Message-Id: <1301982971-4574-1-git-send-email-harsh@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1.1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6, seldom 2.4 (older, 4) X-Received-From: 202.81.31.145 Cc: Harsh Prateek Bora , jvrao@linux.vnet.ibm.com Subject: [Qemu-devel] [PATCH v3] v9fs_walk: As per 9p2000 RFC, MAXWELEM >= nwnames >= 0. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The nwnames field in TWALK message is assumed to be >=0 and <= MAXWELEM which is defined as macro P9_MAXWELEM (16) in virtio-9p.h as per 9p2000 RFC. Appropriate changes are required in V9fsWalkState and v9fs_walk. v3: - Updated if-else conditions to appropriately handle nwnames = 0. v2: - Added check in v9fs_walk_complete as well. Signed-off-by: Harsh Prateek Bora --- hw/9pfs/virtio-9p.c | 7 +++++-- hw/9pfs/virtio-9p.h | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/hw/9pfs/virtio-9p.c b/hw/9pfs/virtio-9p.c index 6c06bb3..1d49970 100644 --- a/hw/9pfs/virtio-9p.c +++ b/hw/9pfs/virtio-9p.c @@ -1621,7 +1621,7 @@ static void v9fs_walk_complete(V9fsState *s, V9fsWalkState *vs, int err) { complete_pdu(s, vs->pdu, err); - if (vs->nwnames) { + if (vs->nwnames && vs->nwnames <= P9_MAXWELEM) { for (vs->name_idx = 0; vs->name_idx < vs->nwnames; vs->name_idx++) { v9fs_string_free(&vs->wnames[vs->name_idx]); } @@ -1717,7 +1717,7 @@ static void v9fs_walk(V9fsState *s, V9fsPDU *pdu) vs->offset += pdu_unmarshal(vs->pdu, vs->offset, "ddw", &fid, &newfid, &vs->nwnames); - if (vs->nwnames) { + if (vs->nwnames && vs->nwnames <= P9_MAXWELEM) { vs->wnames = qemu_mallocz(sizeof(vs->wnames[0]) * vs->nwnames); vs->qids = qemu_mallocz(sizeof(vs->qids[0]) * vs->nwnames); @@ -1726,6 +1726,9 @@ static void v9fs_walk(V9fsState *s, V9fsPDU *pdu) vs->offset += pdu_unmarshal(vs->pdu, vs->offset, "s", &vs->wnames[i]); } + } else if (vs->nwnames >= P9_MAXWELEM) { + err = -EINVAL; + goto out; } vs->fidp = lookup_fid(s, fid); diff --git a/hw/9pfs/virtio-9p.h b/hw/9pfs/virtio-9p.h index 6c6931e..34f9bb3 100644 --- a/hw/9pfs/virtio-9p.h +++ b/hw/9pfs/virtio-9p.h @@ -289,7 +289,7 @@ typedef struct V9fsStatStateDotl { typedef struct V9fsWalkState { V9fsPDU *pdu; size_t offset; - int16_t nwnames; + uint16_t nwnames; int name_idx; V9fsQID *qids; V9fsFidState *fidp;