From patchwork Wed Oct 4 11:36:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prasad Pandit X-Patchwork-Id: 9984373 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4572960237 for ; Wed, 4 Oct 2017 11:38:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3782428173 for ; Wed, 4 Oct 2017 11:38:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2C6BB28A9A; Wed, 4 Oct 2017 11:38:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 2316C28173 for ; Wed, 4 Oct 2017 11:38:04 +0000 (UTC) Received: from localhost ([::1]:34495 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dzi02-000757-Uo for patchwork-qemu-devel@patchwork.kernel.org; Wed, 04 Oct 2017 07:38:02 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40510) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dzhz7-00074k-MQ for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dzhz4-0002Ji-IN for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58258) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dzhz4-0002Gv-Ax for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:02 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 44F9F7EAA0; Wed, 4 Oct 2017 11:37:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 44F9F7EAA0 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=fail smtp.mailfrom=ppandit@redhat.com Received: from localhost.localdomain (unknown [10.33.36.9]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AE4B95D9CB; Wed, 4 Oct 2017 11:36:57 +0000 (UTC) From: P J P To: Qemu Developers Date: Wed, 4 Oct 2017 17:06:52 +0530 Message-Id: <20171004113652.29620-1-ppandit@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Wed, 04 Oct 2017 11:37:00 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH] 9pfs: use g_malloc0 to allocate space for xattr 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: Tuomas Tynkkynen , Greg Kurz , Prasad J Pandit Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Prasad J Pandit 9p back-end first queries the size of an extended attribute, allocates space for it via g_malloc() and then retrieves its value into allocated buffer. Race between querying attribute size and retrieving its could lead to memory bytes disclosure. Use g_malloc0() to avoid it. Reported-by: Tuomas Tynkkynen Signed-off-by: Prasad J Pandit --- hw/9pfs/9p.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 23ac7bb532..f8bbac251d 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -3234,7 +3234,7 @@ static void coroutine_fn v9fs_xattrwalk(void *opaque) xattr_fidp->fid_type = P9_FID_XATTR; xattr_fidp->fs.xattr.xattrwalk_fid = true; if (size) { - xattr_fidp->fs.xattr.value = g_malloc(size); + xattr_fidp->fs.xattr.value = g_malloc0(size); err = v9fs_co_llistxattr(pdu, &xattr_fidp->path, xattr_fidp->fs.xattr.value, xattr_fidp->fs.xattr.len); @@ -3267,7 +3267,7 @@ static void coroutine_fn v9fs_xattrwalk(void *opaque) xattr_fidp->fid_type = P9_FID_XATTR; xattr_fidp->fs.xattr.xattrwalk_fid = true; if (size) { - xattr_fidp->fs.xattr.value = g_malloc(size); + xattr_fidp->fs.xattr.value = g_malloc0(size); err = v9fs_co_lgetxattr(pdu, &xattr_fidp->path, &name, xattr_fidp->fs.xattr.value, xattr_fidp->fs.xattr.len);