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=-6.9 required=3.0 tests=DKIMWL_WL_HIGH,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 95A7FC2D0CE for ; Tue, 21 Jan 2020 13:26:40 +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 62763206A2 for ; Tue, 21 Jan 2020 13:26:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="O0d8/aWU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 62763206A2 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]:53798 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ittYF-00040F-8J for qemu-devel@archiver.kernel.org; Tue, 21 Jan 2020 08:26:39 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:51755) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1itsdm-0008OL-W8 for qemu-devel@nongnu.org; Tue, 21 Jan 2020 07:28:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1itsdj-00035X-68 for qemu-devel@nongnu.org; Tue, 21 Jan 2020 07:28:18 -0500 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:41595 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1itsdi-00034t-7a for qemu-devel@nongnu.org; Tue, 21 Jan 2020 07:28:14 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579609693; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3jSLD5ehJ3ai/ntqwK99Tybgj4IiLz06GbpfP3AIgaQ=; b=O0d8/aWUwm1EhO5AQXGDEMAQCGgrEUUpJk3C1yfkBxOLWIRnnrt8Mojskg6ThUdVn816iN sX072RKbPgzdodfS3emP+EbxtXDIJjfyWeIXqFK4sSQy0qmAViMpfDU2UJ1VOMc1/T7juC GfIClUMTpy16euGS9GAPg4UJmm8jWUQ= 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-339-ubGcTgg8MpStm20SVW_UKQ-1; Tue, 21 Jan 2020 07:28:12 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 66FD21005510; Tue, 21 Jan 2020 12:28:11 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.32]) by smtp.corp.redhat.com (Postfix) with ESMTP id 2E5B860BE0; Tue, 21 Jan 2020 12:28:07 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com, berrange@redhat.com, slp@redhat.com, philmd@redhat.com Subject: [PATCH v2 043/109] virtiofsd: validate input buffer sizes in do_write_buf() Date: Tue, 21 Jan 2020 12:23:27 +0000 Message-Id: <20200121122433.50803-44-dgilbert@redhat.com> In-Reply-To: <20200121122433.50803-1-dgilbert@redhat.com> References: <20200121122433.50803-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: ubGcTgg8MpStm20SVW_UKQ-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com 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: 207.211.31.81 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: , Cc: m.mizuma@jp.fujitsu.com, misono.tomohiro@jp.fujitsu.com 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 Reviewed-by: Sergio Lopez --- tools/virtiofsd/fuse_lowlevel.c | 49 ++++++++++++++++++++------------- 1 file changed, 30 insertions(+), 19 deletions(-) diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowleve= l.c index 84a9d5f993..5ae94cf56b 100644 --- a/tools/virtiofsd/fuse_lowlevel.c +++ b/tools/virtiofsd/fuse_lowlevel.c @@ -1004,8 +1004,8 @@ static void do_write(fuse_req_t req, fuse_ino_t nodei= d, const void *inarg) } } =20 -static void do_write_buf(fuse_req_t req, fuse_ino_t nodeid, const void *in= arg, - struct fuse_bufvec *ibufv) +static void do_write_buf(fuse_req_t req, fuse_ino_t nodeid, + struct fuse_mbuf_iter *iter, struct fuse_bufvec *= ibufv) { struct fuse_session *se =3D req->se; struct fuse_bufvec *pbufv =3D ibufv; @@ -1013,28 +1013,27 @@ static void do_write_buf(fuse_req_t req, fuse_ino_t= nodeid, const void *inarg, .buf[0] =3D ibufv->buf[0], .count =3D 1, }; - struct fuse_write_in *arg =3D (struct fuse_write_in *)inarg; + struct fuse_write_in *arg; + size_t arg_size =3D sizeof(*arg); struct fuse_file_info fi; =20 memset(&fi, 0, sizeof(fi)); + + arg =3D fuse_mbuf_iter_advance(iter, arg_size); + if (!arg) { + fuse_reply_err(req, EINVAL); + return; + } + + fi.lock_owner =3D arg->lock_owner; + fi.flags =3D arg->flags; fi.fh =3D arg->fh; fi.writepage =3D arg->write_flags & FUSE_WRITE_CACHE; =20 if (ibufv->count =3D=3D 1) { - fi.lock_owner =3D arg->lock_owner; - fi.flags =3D arg->flags; - if (!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD)) { - tmpbufv.buf[0].mem =3D PARAM(arg); - } - tmpbufv.buf[0].size -=3D - sizeof(struct fuse_in_header) + sizeof(struct fuse_write_in); - if (tmpbufv.buf[0].size < arg->size) { - fuse_log(FUSE_LOG_ERR, - "fuse: do_write_buf: buffer size too small\n"); - fuse_reply_err(req, EIO); - return; - } - tmpbufv.buf[0].size =3D arg->size; + assert(!(tmpbufv.buf[0].flags & FUSE_BUF_IS_FD)); + tmpbufv.buf[0].mem =3D ((char *)arg) + arg_size; + tmpbufv.buf[0].size -=3D sizeof(struct fuse_in_header) + arg_size; pbufv =3D &tmpbufv; } else { /* @@ -1044,6 +1043,13 @@ static void do_write_buf(fuse_req_t req, fuse_ino_t = nodeid, const void *inarg, ibufv->buf[0].size =3D 0; } =20 + if (fuse_buf_size(pbufv) !=3D arg->size) { + fuse_log(FUSE_LOG_ERR, + "fuse: do_write_buf: buffer size doesn't match arg->size\= n"); + fuse_reply_err(req, EIO); + return; + } + se->op.write_buf(req, nodeid, pbufv, arg->offset, &fi); } =20 @@ -2054,12 +2060,17 @@ void fuse_session_process_buf_int(struct fuse_sessi= on *se, struct fuse_chan *ch) { const struct fuse_buf *buf =3D bufv->buf; + struct fuse_mbuf_iter iter =3D FUSE_MBUF_ITER_INIT(buf); struct fuse_in_header *in; const void *inarg; struct fuse_req *req; int err; =20 - in =3D buf->mem; + /* The first buffer must be a memory buffer */ + assert(!(buf->flags & FUSE_BUF_IS_FD)); + + in =3D fuse_mbuf_iter_advance(&iter, sizeof(*in)); + assert(in); /* caller guarantees the input buffer is large enough */ =20 if (se->debug) { fuse_log(FUSE_LOG_DEBUG, @@ -2131,7 +2142,7 @@ void fuse_session_process_buf_int(struct fuse_session= *se, =20 inarg =3D (void *)&in[1]; if (in->opcode =3D=3D FUSE_WRITE && se->op.write_buf) { - do_write_buf(req, in->nodeid, inarg, bufv); + do_write_buf(req, in->nodeid, &iter, bufv); } else { fuse_ll_ops[in->opcode].func(req, in->nodeid, inarg); } --=20 2.24.1