From patchwork Wed Feb 2 19:39:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Goyal X-Patchwork-Id: 12733442 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 48835C433F5 for ; Wed, 2 Feb 2022 20:14:57 +0000 (UTC) Received: from localhost ([::1]:38614 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nFM1o-0002QB-B4 for qemu-devel@archiver.kernel.org; Wed, 02 Feb 2022 15:14:56 -0500 Received: from eggs.gnu.org ([209.51.188.92]:56178) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nFLTq-0004JA-Cb for qemu-devel@nongnu.org; Wed, 02 Feb 2022 14:39:50 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:51859) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nFLTm-00043i-3l for qemu-devel@nongnu.org; Wed, 02 Feb 2022 14:39:48 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643830784; 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=DAyyRe3fpG6oZ2Jm2YsjkEkcVh4TgOxRMizjL/dBgWc=; b=cxiCbOO/xlkWqqTY/+Wpw6svp8tF2bOSulm/JQKIEknww5TcBbv7/MTq3RYi2UMgDW24V7 c9tIeAxOjYKBXRd7IF6lgAfF041xTmZ0L5iinMTeaD3IsH7PLzmfBBaCmRbW7oaXpHUL5x VkexFSJL8KzjCdmAtWxJf/QCc99Iu3w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-185-gV0ntVOvOvqvK6w6VcBd0Q-1; Wed, 02 Feb 2022 14:39:43 -0500 X-MC-Unique: gV0ntVOvOvqvK6w6VcBd0Q-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7DC6C5109B for ; Wed, 2 Feb 2022 19:39:42 +0000 (UTC) Received: from horse.redhat.com (unknown [10.22.32.185]) by smtp.corp.redhat.com (Postfix) with ESMTP id 415101007607; Wed, 2 Feb 2022 19:39:42 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id BD2EA224570; Wed, 2 Feb 2022 14:39:41 -0500 (EST) From: Vivek Goyal To: qemu-devel@nongnu.org, virtio-fs@redhat.com Subject: [PATCH v5 1/9] virtiofsd: Fix breakage due to fuse_init_in size change Date: Wed, 2 Feb 2022 14:39:27 -0500 Message-Id: <20220202193935.268777-2-vgoyal@redhat.com> In-Reply-To: <20220202193935.268777-1-vgoyal@redhat.com> References: <20220202193935.268777-1-vgoyal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=vgoyal@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=170.10.129.124; envelope-from=vgoyal@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.086, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mszeredi@redhat.com, dgilbert@redhat.com, vgoyal@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Kernel version 5.17 has increased the size of "struct fuse_init_in" struct. Previously this struct was 16 bytes and now it has been extended to 64 bytes in size. Once qemu headers are updated to latest, it will expect to receive 64 byte size struct (for protocol version major 7 and minor > 6). But if guest is booting older kernel (older than 5.17), then it still sends older fuse_init_in of size 16 bytes. And do_init() fails. It is expecting 64 byte struct. And this results in mount of virtiofs failing. Fix this by parsing 16 bytes only for now. Separate patches will be posted which will parse rest of the bytes and enable new functionality. Right now we don't support any of the new functionality, so we don't lose anything by not parsing bytes beyond 16. Reviewed-by: Dr. David Alan Gilbert Signed-off-by: Vivek Goyal --- tools/virtiofsd/fuse_lowlevel.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c index e4679c73ab..ce29a70253 100644 --- a/tools/virtiofsd/fuse_lowlevel.c +++ b/tools/virtiofsd/fuse_lowlevel.c @@ -1880,6 +1880,7 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, struct fuse_mbuf_iter *iter) { size_t compat_size = offsetof(struct fuse_init_in, max_readahead); + size_t compat2_size = offsetof(struct fuse_init_in, flags) + sizeof(uint32_t); struct fuse_init_in *arg; struct fuse_init_out outarg; struct fuse_session *se = req->se; @@ -1897,7 +1898,7 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid, /* ...and now consume the new fields. */ if (arg->major == 7 && arg->minor >= 6) { - if (!fuse_mbuf_iter_advance(iter, sizeof(*arg) - compat_size)) { + if (!fuse_mbuf_iter_advance(iter, compat2_size - compat_size)) { fuse_reply_err(req, EINVAL); return; }