From patchwork Tue Feb 8 20:48:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vivek Goyal X-Patchwork-Id: 12739305 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 89674C433FE for ; Tue, 8 Feb 2022 21:06:19 +0000 (UTC) Received: from localhost ([::1]:39272 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nHXgo-0002kI-DQ for qemu-devel@archiver.kernel.org; Tue, 08 Feb 2022 16:06:18 -0500 Received: from eggs.gnu.org ([209.51.188.92]:47760) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nHXPh-0002Ou-1E for qemu-devel@nongnu.org; Tue, 08 Feb 2022 15:48:37 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:44591) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nHXPb-00044i-FS for qemu-devel@nongnu.org; Tue, 08 Feb 2022 15:48:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1644353311; 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=bN28y/WI3eyvQ7U9alg3cH0zTFxXd9+QPy79B5HPvIZpYBU/DFKom7y2I/EjSN+jRUJGDR b+8ZhS0fzh/m3tRjA6MMG0DMg40hNq9J46yBwQ/9Y5annFP56wCEQTXZ7MiDgnnKrhi3v1 M/LSEla8epvRBAsugJYc3XSMcDQxjnU= 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-517-77zbo-bYPlmd8LszalRvPA-1; Tue, 08 Feb 2022 15:48:25 -0500 X-MC-Unique: 77zbo-bYPlmd8LszalRvPA-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3DB621F6B1 for ; Tue, 8 Feb 2022 20:48:24 +0000 (UTC) Received: from horse.redhat.com (unknown [10.22.18.12]) by smtp.corp.redhat.com (Postfix) with ESMTP id 20F3C5E26C; Tue, 8 Feb 2022 20:48:24 +0000 (UTC) Received: by horse.redhat.com (Postfix, from userid 10451) id B1B832256F6; Tue, 8 Feb 2022 15:48:23 -0500 (EST) From: Vivek Goyal To: qemu-devel@nongnu.org, virtio-fs@redhat.com Subject: [PATCH v6 01/10] virtiofsd: Fix breakage due to fuse_init_in size change Date: Tue, 8 Feb 2022 15:48:04 -0500 Message-Id: <20220208204813.682906-2-vgoyal@redhat.com> In-Reply-To: <20220208204813.682906-1-vgoyal@redhat.com> References: <20220208204813.682906-1-vgoyal@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 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: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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, berrange@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; }