From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2375ECA9EAF for ; Thu, 24 Oct 2019 12:15:32 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DF50A20679 for ; Thu, 24 Oct 2019 12:15:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="ihtJKcvf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF50A20679 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:40740 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNc1a-0003de-6n for qemu-devel@archiver.kernel.org; Thu, 24 Oct 2019 08:15:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39350) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNbHu-0003Pp-Ct for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:28:19 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNbHs-0008UA-Nr for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:28:18 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:41147 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iNbHq-0008Tb-5P for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:28:14 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571916493; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Kc/gbo+upybElFbY3/lui49elaqZGdHA6I+6dPD8EcM=; b=ihtJKcvfyxYZ9bPKub7BTVUp1SUWPHh5cxSmlzEQkcsksKxZBAovxR0vGBuOLYgrih9Cq0 UCKkF/lOd9jw0veBkvN34ZuJfEavsdoEgLan4Farq571rRTjByHFzALP4D5q4qYoUUkim8 TwgcihL3dWDnu92nUCGa55iF7WBCNuY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-184-uPdozyFLNn2UnDCjrxYpvA-1; Thu, 24 Oct 2019 07:28:09 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 51B98107AD31; Thu, 24 Oct 2019 11:28:08 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-117-248.ams2.redhat.com [10.36.117.248]) by smtp.corp.redhat.com (Postfix) with ESMTP id CB4A74524; Thu, 24 Oct 2019 11:28:05 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, renzhen@linux.alibaba.com, eguan@linux.alibaba.com, ganesh.mahalingam@intel.com, m.mizuma@jp.fujitsu.com, mszeredi@redhat.com, misono.tomohiro@jp.fujitsu.com, tao.peng@linux.alibaba.com, piaojun@huawei.com, stefanha@redhat.com, vgoyal@redhat.com, mst@redhat.com, berrange@redhat.com Subject: [PATCH 11/25] virtiofsd: validate input buffer sizes in do_write_buf() Date: Thu, 24 Oct 2019 12:27:04 +0100 Message-Id: <20191024112718.34657-12-dgilbert@redhat.com> In-Reply-To: <20191024112718.34657-1-dgilbert@redhat.com> References: <20191024112718.34657-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: uPdozyFLNn2UnDCjrxYpvA-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 205.139.110.120 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi There is a small change in behavior: if fuse_write_in->size doesn't match the input buffer size then the request is failed. Previously write requests with 1 fuse_buf element would truncate to fuse_write_in->size. Signed-off-by: Stefan Hajnoczi --- contrib/virtiofsd/fuse_lowlevel.c | 62 +++++++++++++++++++------------ 1 file changed, 38 insertions(+), 24 deletions(-) diff --git a/contrib/virtiofsd/fuse_lowlevel.c b/contrib/virtiofsd/fuse_low= level.c index 2bd2ba00b9..7927348398 100644 --- a/contrib/virtiofsd/fuse_lowlevel.c +++ b/contrib/virtiofsd/fuse_lowlevel.c @@ -1006,7 +1006,8 @@ static void do_write(fuse_req_t req, fuse_ino_t nodei= d, const void *inarg) =09=09fuse_reply_err(req, ENOSYS); } =20 -static void do_write_buf(fuse_req_t req, fuse_ino_t nodeid, const void *in= arg, +static void do_write_buf(fuse_req_t req, fuse_ino_t nodeid, +=09=09=09 struct fuse_mbuf_iter *iter, =09=09=09 struct fuse_bufvec *ibufv) { =09struct fuse_session *se =3D req->se; @@ -1015,34 +1016,36 @@ static void do_write_buf(fuse_req_t req, fuse_ino_t= nodeid, const void *inarg, =09=09.buf[0] =3D ibufv->buf[0], =09=09.count =3D 1, =09}; -=09struct fuse_write_in *arg =3D (struct fuse_write_in *) inarg; +=09struct fuse_write_in *arg; +=09size_t arg_size =3D sizeof(*arg); =09struct fuse_file_info fi; =20 =09memset(&fi, 0, sizeof(fi)); + +=09if (se->conn.proto_minor < 9) { +=09=09arg_size =3D FUSE_COMPAT_WRITE_IN_SIZE; +=09} + +=09arg =3D fuse_mbuf_iter_advance(iter, arg_size); +=09if (!arg) { +=09=09fuse_reply_err(req, EINVAL); +=09=09return; +=09} + +=09/* Only access non-compat fields here! */ +=09if (se->conn.proto_minor >=3D 9) { +=09=09fi.lock_owner =3D arg->lock_owner; +=09=09fi.flags =3D arg->flags; +=09} + =09fi.fh =3D arg->fh; =09fi.writepage =3D arg->write_flags & FUSE_WRITE_CACHE; =20 =09if (ibufv->count =3D=3D 1) { -=09=09if (se->conn.proto_minor < 9) { -=09=09=09tmpbufv.buf[0].mem =3D ((char *) arg) + FUSE_COMPAT_WRITE_IN_SIZE= ; -=09=09=09tmpbufv.buf[0].size -=3D sizeof(struct fuse_in_header) + -=09=09=09=09FUSE_COMPAT_WRITE_IN_SIZE; -=09=09=09assert(!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD)); -=09=09} else { -=09=09=09fi.lock_owner =3D arg->lock_owner; -=09=09=09fi.flags =3D arg->flags; -=09=09=09if (!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD)) -=09=09=09=09tmpbufv.buf[0].mem =3D PARAM(arg); - -=09=09=09tmpbufv.buf[0].size -=3D sizeof(struct fuse_in_header) + -=09=09=09=09sizeof(struct fuse_write_in); -=09=09} -=09=09if (tmpbufv.buf[0].size < arg->size) { -=09=09=09fuse_log(FUSE_LOG_ERR, "fuse: do_write_buf: buffer size too small= \n"); -=09=09=09fuse_reply_err(req, EIO); -=09=09=09return; -=09=09} -=09=09tmpbufv.buf[0].size =3D arg->size; +=09=09assert(!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD)); +=09=09tmpbufv.buf[0].mem =3D ((char *) arg) + arg_size; +=09=09tmpbufv.buf[0].size -=3D sizeof(struct fuse_in_header) + +=09=09=09=09 arg_size; =09=09pbufv =3D &tmpbufv; =09} else { =09=09// Input bufv contains the headers in the first element @@ -1050,6 +1053,12 @@ static void do_write_buf(fuse_req_t req, fuse_ino_t = nodeid, const void *inarg, =09=09ibufv->buf[0].size =3D 0; =09} =20 +=09if (fuse_buf_size(pbufv) !=3D arg->size) { +=09=09fuse_log(FUSE_LOG_ERR, "fuse: do_write_buf: buffer size doesn't matc= h arg->size\n"); +=09=09fuse_reply_err(req, EIO); +=09=09return; +=09} + =09se->op.write_buf(req, nodeid, pbufv, arg->offset, &fi); } =20 @@ -2002,12 +2011,17 @@ void fuse_session_process_buf_int(struct fuse_sessi= on *se, =09=09=09=09 struct fuse_bufvec *bufv, struct fuse_chan *ch) { =09const struct fuse_buf *buf =3D bufv->buf; +=09struct fuse_mbuf_iter iter =3D FUSE_MBUF_ITER_INIT(buf); =09struct fuse_in_header *in; =09const void *inarg; =09struct fuse_req *req; =09int err; =20 -=09in =3D buf->mem; +=09/* The first buffer must be a memory buffer */ +=09assert(!(buf->flags & FUSE_BUF_IS_FD)); + +=09in =3D fuse_mbuf_iter_advance(&iter, sizeof(*in)); +=09assert(in); /* caller guarantees the input buffer is large enough */ =20 =09if (se->debug) { =09=09fuse_log(FUSE_LOG_DEBUG, @@ -2074,7 +2088,7 @@ void fuse_session_process_buf_int(struct fuse_session= *se, =20 =09inarg =3D (void *) &in[1]; =09if (in->opcode =3D=3D FUSE_WRITE && se->op.write_buf) -=09=09do_write_buf(req, in->nodeid, inarg, bufv); +=09=09do_write_buf(req, in->nodeid, &iter, bufv); =09else =09=09fuse_ll_ops[in->opcode].func(req, in->nodeid, inarg); =20 --=20 2.23.0